JPH0415525B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for adjusting a viewing device relative to a cylinder prior to positioning a magnetic head relative to the cylinder.

(Prior art) When adjusting the position of a magnetic head relative to a cylinder in a VTR device, etc., the cylinder is supported on the support by first inserting the spindle of the support into a circular hole formed in the center of the cylinder. The magnetic head is photographed by a television camera having an optical axis perpendicular to the circumferential surface of the cylinder, and the magnetic head is displayed on a monitor television based on signals from the television camera. Then, the position of the magnetic head is adjusted so that the specific part of the magnetic head matches the vertical reference line simultaneously displayed on the monitor television.

In order to adjust the position of the magnetic head with respect to the cylinder with high precision, it is necessary to set the relative positional relationship between the cylinder and the television camera with high precision.

Therefore, in the past, the TV camera was previously installed in a fixed relative positional relationship with the spindle of the support base, and the spindle was tapered and inserted into the hole of the cylinder, and the cylinder was positioned by the action of the taper. Was. As a result, the relative positional relationship between the television camera and the cylinder is set.

Also, after inserting the support shaft into the cylinder hole,
Another method was to inflate the spindle with air to center the cylinder and position it.

(Problem to be solved by the invention) However, with the above conventional means, it is difficult to form the spindle with high precision, so there is a limit to improving the positioning accuracy of the cylinder, and as a result, the magnetic head It was not possible to adjust the position with high precision. This drawback was particularly noticeable when the cylinder had a small diameter and the support shaft supporting the cylinder had a small diameter.

Furthermore, when assembling VTR equipment, etc., the center of rotation of the cylinder to which the magnetic head is attached is made to coincide with the center point of its outer circumference with high precision. Therefore, the outer circumferential circle of the cylinder and its center serve as a reference for positioning the magnetic head. In the conventional method described above, in which the center point of the hole in the center of the cylinder is aligned with the center of the spindle, if the center point of this hole is slightly shifted from the center point of the outer circumference of the cylinder, the magnetic head It was not possible to adjust the position with high precision with respect to the outer circumference of the cylinder.

(Means for Solving the Problems) The present invention has been made to solve the above problems, and the gist thereof is to use a non-contact type sensor installed at a predetermined position prior to adjusting the position of the magnetic head. The gap between this sensor and multiple points on the circumferential surface of the supported cylinder is measured, and based on the measurement results, the arithmetic circuit calculates the position of the center point of the cylinder's outer circumference, and calculates the result of this calculation. Based on this, focusing is performed by moving the TV camera in the direction of its optical axis, and by moving the vertical reference line on the monitor TV horizontally, the vertical reference line is moved to the center point position of the outer circumferential circle of the cylinder. A method of adjusting an observation device with respect to a cylinder for supporting a magnetic head, characterized in that the observation device is adjusted to match the cylinder for supporting a magnetic head.

(Function) The TV camera is focused based on the center point position of the outer circumference of the cylinder, and
By adjusting the position of the vertical reference line of the monitor TV, the position of the magnetic head relative to the cylinder can be determined with high precision, regardless of the center point of the hole being offset from the center point of the cylinder's outer circumference. Adjustments can be made.

Since the observation device is adjusted based on the detection of the circumferential surface of the cylinder, the position of the magnetic head can be adjusted with high precision without being affected by dimensional errors of the support shaft. Further, since it is not necessary to perform strict centering of the cylinder using the support shaft, the manufacture of the support shaft and the like becomes easier. Furthermore, the position of the magnetic head can be adjusted with high precision even for small diameter cylinders.

Since the observation device is adjusted, it is not necessary to provide the support stand with a function for adjusting the position of the cylinder, and the structure of the support stand can be simplified and backlash can be reduced. As a result, it is possible to prevent minute displacement of the cylinder when a load is applied to the cylinder, and from this point of view as well, the position of the magnetic head can be adjusted with high precision.

Furthermore, since the observation device is automatically adjusted, no human effort is required, and work efficiency can be improved.

(Example) An example of the present invention will be described below with reference to FIGS. 1 to 3. Reference numeral 1 in FIG. 1 is a cylinder whose peripheral surface 1a is a cylindrical surface and has a circular hole 1b in the center, and a plurality of, for example, two magnetic heads 2 can be attached to the peripheral edge of the upper surface. There is.

The cylinder 1 is supported by a support mechanism 10 shown in FIG. This support mechanism 10 has a cylindrical support 11 fixed to a base 5. The upper surface of this support base 11 is flat and serves as a mounting surface 11a. A support shaft 12 is provided protruding from the center of this mounting surface 11a.
Then, this support shaft 12 is connected to the hole 1 of the cylinder 1.
b, and the cylinder 1 is placed on the mounting surface 11a. The cylinder 1 is pressed down from above by a pressing member 13 and supported by a support base 11. This pressing member 13 is fixed to the rod 14 of the air cylinder, and can hold the cylinder 1 when the air cylinder is extended.

As shown in FIG. 1, for example, a capacitance type (non-contact type) sensor 20 is installed around the support mechanism 10.
A total of four are arranged at 90° intervals. These sensors 20 are spaced the same distance from the support shaft 12 of the support base 11, and are arranged close to the circumferential surface of the cylinder 1 in the supported state. These sensors 20
is set at the upper end of the support stand 21 fixed to the base 5, as shown in FIG.

On the left and right sides of the support mechanism 10, there are two television cameras 26 facing each other 180 degrees around the support shaft 12.
26 are arranged. The optical axes 26a of the optical systems housed inside the two television cameras 26 are aligned with each other, and the cylinder 1 in the supported state
is perpendicular to the circumferential surface 1a. Each TV camera 26
The television camera 26 is for photographing the magnetic head 2 whose position is to be adjusted with respect to the cylinder 1 as will be described later, and a monitor television 28 is connected to this television camera 26 via a video signal generating circuit 27. The video signal generation circuit 27 generates a television video signal based on an image signal from the television camera 26,
The vertical reference line signal is sent to the monitor television 28, on which the magnetic head 2 photographed by the television camera 26 and the vertical reference line 29 are simultaneously displayed.

The television camera 26 and the video signal generation circuit 27
and monitor television 28, observation device 25
is configured.

Each television camera 26 is connected to a moving stage mechanism 30.
is supported by This moving stage mechanism 30
As shown in FIG. 3, the fixed stage 31 fixed to the base 5 and the
It has an X stage 32 that is movable in the axial direction (direction along the optical axis 26a of the television camera 26), and the television camera 26 is mounted on the X stage 32.
is fixed.

The X stage 32 of each moving stage mechanism 30 is
They are each moved by a moving mechanism 40.

As shown in FIG. 3, each moving mechanism 40 includes a cylindrical case 42 fixed to a support base 41, a hollow rod 43 inserted into the distal end of the case 42 in a slidable but non-rotatable manner, and a case 42. 42, a reduction gear train 45 connected to an output shaft 44a of the motor 44, and a rotating shaft 46 connected to the reduction gear train 45. A male threaded portion 46a is formed at the tip of the rotating shaft 46.
is screwed into a female threaded portion 43a formed on the inner circumferential surface of the rod 43.

For example, when the motor 44 rotates normally, the rotating shaft 46 rotates at a reduced speed, and the male threaded portion 46 rotates at a reduced speed.
The rod 43 moves forward due to the screw action between the threaded portion 43a and the female threaded portion 43a. Further, as the motor 44 is reversed, the rod 43 is moved backward.

The X stage 32 is urged in the direction of the rod 43 of the moving mechanism 40 by the action of a spring (not shown).
2 is always in contact with the tip of the rod 43 and is moved following the advance and retreat of this rod 43.

As shown in FIG. 1, the four sensors 20 are connected to an arithmetic circuit 51 via an amplifier 50. A focus control circuit 52 is connected to the arithmetic circuit 51, and the motor 44 of each moving mechanism 40 is controlled by this control circuit 52.

Further, a line control circuit 53 is connected to the arithmetic circuit 51, and the position of the vertical reference line 29 on the monitor television 28 is controlled by this control circuit 53.

The present invention is carried out using the above device. First, the cylinder 1 before the magnetic head 2 is attached is supported by the support mechanism 10 as described above. While the cylinder 1 is in a stationary and supported state, the four sensors 20 measure the gaps between these sensors 20 and four locations on the circumferential surface 1a of the cylinder 1 that face them. This measurement signal is amplified by an amplifier 50 and sent to an arithmetic circuit 51. The arithmetic circuit 51 analyzes the center point position of the outer circumferential circle of the cylinder 1 and the outer diameter (in this embodiment, even if there is an error in the outer diameter). ) is calculated.

The above calculation results are sent to the focus control circuit 52, and each motor 44 of the two moving mechanisms 40 is driven based on a control signal from the focus control circuit 52. By driving this motor 44, the X stage 32 of the moving stage mechanism 30 is moved.
The position of each television camera 26 is adjusted in the X-axis direction. As a result, each television camera 26 is focused on a position protruding from the circumferential surface of the cylinder 1 by more than 20 microns.

Further, the above calculation result is sent to the line control circuit 53. This control circuit 53 horizontally moves the vertical reference line 29 on the monitor television 28 so that the vertical reference line 29 coincides with the center point of the outer circumferential circle of the cylinder 1 on the monitor television 28 .

Thereafter, the magnetic head 2 is held against the peripheral edge of the upper surface of the cylinder 1 while being held by a holding mechanism (not shown). Then, the positions of the magnetic heads 2 are adjusted so that the specific positions of the gaps 2a of the two magnetic heads 2 displayed on each monitor television 28 coincide with the vertical reference line 29, respectively. Since the vertical reference line 29 coincides with the center point of the outer circumferential circle of the cylinder 1 due to the above-mentioned adjustment, the vertical reference line 29
By aligning the magnetic heads 2 with the magnetic heads 9, the two magnetic heads 2 are accurately positioned 180° opposite each other.

The magnetic head 2 is located from the circumferential surface of the cylinder 1.
Although it is positioned so as to protrude by more than 20 microns, the television camera 26 has been previously focused on this position by the adjustment described above, so that a clear image of the magnetic head 2 is displayed on the monitor television 28.

In addition, elliptical stripes are generated when light is irradiated onto the magnetic head 2 from an optical device (not shown) attached to the television camera 26, and the reflected light interferes with the reflected light from a mirror built into the optical device. The pattern is photographed by a television camera 26 and displayed on a monitor television 28, and the amount of protrusion and attitude of the magnetic head 2 are adjusted so that the striped pattern has a prescribed shape and appears at a prescribed position.

After the above position adjustment, the magnetic head 2 is attached to the cylinder 1.

As described above, focusing is performed by adjusting the relative position of the television camera 26 with respect to the cylinder 1 based on the center point position of the outer circumference of the cylinder 1, and the vertical reference line 29 is also adjusted, so that the center of the hole 1b is adjusted. Even if the point is offset from the center point of the outer circle, the magnetic head 2
The position can be adjusted with high precision.

Furthermore, since the observation device 25 is adjusted based on the detection of the peripheral surface 1a of the cylinder 1, the support shaft 1
The position of the magnetic head 2 can be adjusted with high accuracy without being affected by dimensional errors in the magnetic head 2.

Furthermore, since the observation device 25 is adjusted, there is no need to provide the support stand 11 with a function for adjusting the position of the cylinder, and the structure of the support stand 11 can be simplified and backlash can be reduced. Even if a load is applied to cylinder 1 during installation,
It is possible to prevent minute displacement from occurring in the cylinder 1. Therefore, also from this point of view, the position of the magnetic head 2 can be adjusted with high precision.

Note that the magnetic head 2 may be attached to the cylinder 1 in advance, and after the cylinder 1 is supported on the support stand 11 and the observation device 25 is adjusted, the magnetic head 2 may be slightly corrected to an accurate position. .

FIG. 4 shows a schematic diagram of an apparatus for carrying out another embodiment of the method of the invention. In the drawings, constituent members corresponding to the above embodiments are given the same numbers and detailed explanation thereof will be omitted. In this embodiment, the observation device 25
There is only one set of sensors 20, and one sensor 20 is not arranged. Further, a support stand 11' that supports the cylinder 1 is connected to a motor 60 to be rotated, and the rotation angle of the support stand 11' and the cylinder 1 is detected by a rotary encoder 61 and an angle counter 62. .

In this embodiment, first, one sensor 20,
The gaps between the four points on the circumferential surface of the cylinder 1 are detected. Specifically, the angle setting circuit 63 sets 360°, and outputs this set angle signal to the angular deviation generation circuit 64. The angle deviation generating circuit 64 outputs the deviation between the set angle signal and the detected angle signal from the angle counter 62 to the drive circuit 65. As a result, the motor 60 is driven by the drive circuit 65. When the above deviation becomes zero, the motor 60
In other words, it stops when the cylinder 1 rotates 360 degrees. During this rotation, a measurement signal regarding the gap between the sensor 20 and the circumferential surface 1a of the cylinder 1 passing through the sensor 20 is amplified by the amplifier 66.
It is sent to the angle/displacement data generation circuit 67. In this circuit 67, based on the detected angle information from the angle counter 62, the sensor 2
The gap information from 0 is sampled and the arithmetic circuit 6
Output to 8. The calculation circuit 68 calculates the center point position and outer diameter of the outer circumference of the stationary cylinder 1 when the magnetic head 2 is attached based on the gap information for each 90° rotation, and the calculation results are sent to the data storage circuit. Send it to 69 and have it memorized.

In the stopped state after the cylinder 1 has rotated once as described above, the focus control circuit 70 drives the motor of the moving mechanism 40 based on the calculation result stored in the data storage circuit 69.
The position of the television camera 26 is adjusted in the X-axis direction. Further, the line control circuit 71 adjusts the position of the vertical reference line 29.

Next, connect one magnetic head 2 to the monitor TV 2.
Adjust the position while watching 8 and attach it to cylinder 1.

Next, the angle setting circuit 63 sets 180°, and the cylinder 1 is rotated 180° by driving the motor 60. In the subsequent stopped state, the focus control circuit 70 again controls the movement mechanism 4 based on the calculation result stored in the storage data circuit 69.
0 to adjust the position of the television camera 26 in the X-axis direction, and the line control circuit 7
1 to adjust the position of the vertical reference line 29. After this, the other magnetic head 2 is adjusted in position and attached to the cylinder 1.

(Effects of the Invention) As explained above, in the present invention, even if the center point of the cylinder hole is offset from the center point of the outer circumferential circle or there is a dimensional error in the support shaft, the cylinder can be magnetically The head can be positioned with high precision.

Furthermore, the structure of the support base can be simplified and backlash can be reduced, and from this point of view as well, the position of the magnetic head can be adjusted with high precision.

Furthermore, it becomes easier to manufacture the support shaft, etc., and
The position of the magnetic head can be adjusted with high precision even for small diameter cylinders.

In addition, since the observation device is automatically adjusted,
Work efficiency can be improved without the need for manpower.

[Brief explanation of drawings]

Fig. 1 is a plan view including an electric circuit showing an apparatus for carrying out an embodiment of the method of the present invention, Fig. 2 is a vertical sectional view of a cylinder and a support, and Fig. 3 shows a mechanism for moving a television camera. The cross-sectional view shown in FIG. 4 is a plan view including the electrical circuitry of an apparatus for carrying out another embodiment of the method of the invention. 1...Cylinder, 1a...Surrounding surface, 1b...
Hole, 2...Magnetic head, 11, 11'...Support stand,
12...Spindle, 20...Sensor, 25...Observation device, 26...Television camera, 28...Monitor TV, 29...Vertical reference line, 30...Movement stage mechanism, 40A, 40B...Movement mechanism ,51,6
8... Arithmetic circuit, 52, 70... Focus control circuit, 53, 71... Line control circuit.

Claims (1)

[Scope of Claims] 1. A support shaft of a support stand is inserted into a hole formed in the center of a cylinder for supporting a magnetic head, and the cylinder is supported on the support stand, and an optical axis perpendicular to the peripheral surface of the cylinder in this supported state. Observe the magnetic head using an observation device equipped with a television camera having a camera and a monitor television connected to the television camera, and align a specific part of the magnetic head with a vertical reference line displayed on the monitor television. In the process of adjusting the position of the magnetic head relative to the cylinder, prior to adjusting the position of the magnetic head, a non-contact sensor installed at a predetermined position detects the relationship between this sensor and the circumferential surface of the supported cylinder. The gaps between multiple points are measured, and based on the measurement results, a calculation circuit calculates the position of the center point of the outer circumference of the cylinder.Based on the calculation results, the television camera is moved in the direction of its optical axis. Focusing is performed by moving the
A method for adjusting an observation device for a magnetic head supporting cylinder, characterized in that the vertical reference line on the monitor television is moved horizontally so that the vertical reference line coincides with the center point of the outer circumferential circle of the cylinder. 2. A plurality of the sensors are arranged, and when the cylinder is stationary, information about the gaps between the sensor and the corresponding plurality of locations on the circumferential surface of the cylinder can be obtained from each sensor. A method for adjusting an observation device for the magnetic head supporting cylinder according to item 1. 3. According to claim 1, the number of the sensors is one, and information about gaps between the sensor and a plurality of locations on the circumferential surface of the cylinder can be obtained from the sensor by rotating the support base. A method of adjusting an observation device to a cylinder for supporting a magnetic head.