JPH0664891B2 - Standard sheet - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a standard sheet used for adjustment or reference of a rotary magnetic sheet device having an annular track for an electronic still camera or the like.

2. Description of the Related Art In the conventional standard sheet shown in FIG. 4, for example, a recording track 101 is formed in an annular shape with a radius r around the recording center a, and a standard signal is reproduced on the recording track 101 when recording. It is recorded at the head position at an angle θ from the lines A and B connecting the time centers B. Since the angle θ is not managed, the head position is random, and the azimuth angle α generated when the recording center a and the reproducing center b are eccentric by δ is also random.

Problems to be Solved by the Invention However, in the conventional standard sheet shown in FIG. 4 as described above, the azimuth difference α that occurs when the recording center B and the reproducing center B are decentered by δ is, for example, δ = 0.01 mm r = 15mm,
When θ = 90 °, the azimuth difference α = 2.3 'and the azimuth difference of 2'or more results only in eccentricity, making it impossible to read the accurate azimuth angle, which is not suitable for handling fine azimuth angles. was there.

Means for Solving the Problems In order to solve the above problems, the standard sheet of the present invention engages with a spindle for rotating a magnetic sheet provided in a magnetic recording / reproducing apparatus, and a rotating magnetic disk for magnetic recording or reproducing. A sheet, wherein the rotation center of the rotating magnetic sheet has an abutting portion that abuts on the spindle when engaged with the spindle to position the rotation of the rotating magnetic sheet, and the abutting portion on the spindle. A center core having an elastic member that presses and abuts is provided, and the standard signal is recorded at a position perpendicular to the direction in which the elastic member presses the abutting portion against the spindle.

Operation According to the present invention, by deciding the position of the standard signal with respect to the center core for positioning the standard sheet, it becomes possible to arrange the standard signal at a position which is most unaffected by the eccentricity of the standard sheet. Since the azimuth difference due to the eccentricity is eliminated, it is possible to adjust the azimuth angle with high accuracy.

Example A standard sheet of the present invention, which is not affected by eccentricity, will be described below with reference to the drawings.

FIG. 1 shows the structure of a rotating magnetic sheet used in an embodiment of the present invention, FIG. 2 is a sectional view showing engagement of a center core and a spindle, and FIGS. 3 (a) and 3 (b) show standard signal patterns. It is shown. Reference numeral 1 is a magnetic sheet, 2 is a center core provided at the center of the magnetic sheet 1, and has a hole 3 smaller than a spindle diameter for engaging with a spindle 20 on the apparatus main body side as shown in FIG. When engaged, the abutting portion 4 is pressed against the spindle 20 by the elastic member 5, and the magnetic sheet 1
The center core 2 is provided with a PG pin 6 for positioning the center of rotation of the magnetic sheet 1 and the center of rotation of the spindle 20. The rotating magnetic sheet having the above-described structure has an annular track. Standard signals 7,8,9,10 shown in FIG. 3 (a)
Are burst signals of azimuth -a ', -b', + b ', + a', respectively. These are detected by the PG pin 6 to detect the rotational phase of the magnetic sheet 1 and the pressing direction of the elastic member 5, that is, the first signal. A direction perpendicular to the arrow C direction in the figure, that is, D in the D and E directions in FIG.
Alternatively, it is recorded at a position having a phase difference of 90 ° or 270 ° from the detection signal 11 of the PG pin 6 shown in FIG. By recording the standard signal at the D or E position as described above, a standard sheet in which the influence of eccentricity is eliminated can be obtained.

EFFECTS OF THE INVENTION As described above, according to the present invention, it is possible to easily produce a standard sheet that is not affected by eccentricity, and it is possible to obtain excellent effects such as highly accurate adjustment and detection of azimuth.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a rotating magnetic sheet according to an embodiment of the present invention, FIG. 2 is a sectional view showing engagement between a center core and a spindle,
FIG. 3 is a waveform diagram showing a standard signal pattern, and FIG. 4 is a schematic diagram showing generation of azimuth due to conventional eccentricity. 1 ... Magnetic sheet, 2 ... Center core, 4 ... Contact part, 5 ... Elastic member, 6 ... PG pin, 20 ... Center core.

Claims (1)

[Claims] 1. A rotary magnetic sheet for magnetically recording or reproducing by engaging a spindle for rotating a magnetic sheet provided in a magnetic recording / reproducing apparatus, wherein the spindle is provided at a rotation center of the rotary magnetic sheet. A center core having an abutting portion that abuts on the spindle when engaged with and positions the rotation of the rotating magnetic sheet, and an elastic member that presses the abutting portion against the spindle for abutting. A standard sheet, wherein a standard signal is recorded at a position perpendicular to a direction in which the elastic member presses the contact portion against the spindle.