JPS60236111A - Automatic positioning system of video head - Google Patents

Abstract

PURPOSE:To provide higher accuracy in positioning and higher stability of a product and to enable unmanned adjusting operation by positioning automatically video heads according to a prescribed program. CONSTITUTION:A base 13 on which a head drum 1 provided with the video heads 2A, 2B facing each other, a drum clamping mechanism 14 which has a tapered part 18 butting against the shaft hole 1A of the drum 1, cameras 22A, 22B which pick up the respective images of the video heads, a stage 25 which is rotated by each slight angle by a motor 26, a cam 27 which adjusts the position of the video heads by the rotation of the output shaft 52A thereof and a control device which executes the prescribed program are provided. The control device runs the motor 26 to the position where the other head gap coincides with the head gap of the video head picked up by one camera as a reference. The control device positions the video heads by the cam 27 during this time. The video heads are thus automatically positioned according to the prescribed program.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic video head positioning system for automatically positioning video heads provided on head drums so as to face each other.

Generally, a head drum for a VTR is equipped with one or two pairs of video tapes facing each other on its outer periphery, and by rotating the head drum, recording is performed on the recording track of the video tape. It is being done as it is. At this time, in order for each video head to face each recording track of the video tape, each video head must be positioned accurately.

For this reason, the video head positioning device according to the prior art was constructed as shown in FIG.

That is, video heads 2A and 2B are provided on the head drum 1 via screws 3A and 3B so as to face each other, and the head drum 1 has a shaft hole IA located at the center of the shaft for mounting a rotating shaft. Adjustment holes IB and IB are also bored near each video head 2A and 2B.

Reference numeral 4 denotes a mounting table on which the head drum 1 is placed, and the mounting table 4 is formed with a fitting shaft 4A that fits into one shaft hole and a reference surface 4B. Reference numeral 5 denotes a screw type drum clamp for fixing the head drum 1 on the mounting table 4, and the drum clamp 5 is screwed into a screw hole (not shown) drilled in the fitting shaft 4A. Fix the head drum 1. 6A, 6B
7A and 7B are optical systems provided on each of the XY stages 6A and 6B;
Reference numerals A and 8B indicate television cameras installed in each party system, and reference numerals 9A and 9B indicate monitor televisions for displaying images taken by the respective television cameras 8A and 8B. In the figure, 10 is the adjustment hole IB of the head drum l.
The eccentric shirt inserted into the video and adjusting the rads 2A, 2B) f is shown.

Using the positioning device with such a configuration, the video head 2A
, 2B are adjusted in the following steps.

■ First, fix the master r-zo with marking lines at 180 degrees opposite positions to the mounting table 4, and
Manually operate B to align the optical systems 7A and 7B with the cross-shaped reference line &(
(see Figure 8), align the Master Gu Zonoke with the key line, 18
Perform 0 degree adjustment accurately.

Next, the drum 1 is placed on the mounting table 4, the drum clamp 5 is screwed on, the shaft hole IA is positioned on the fitting shaft 4A, and the shaft hole IA is brought into close contact with the reference surface 48.

(5) (2) Observe the head gap b (see FIG. 8) of each video head 2A, 2B using the eyepieces of the optical systems 7A, 7B, or observe the head gap fbf using the monitor televisions 9A, 9B.

■For two video heads on one side, if the head gap b deviates from the reference line a as shown in FIG. 8(A), insert the eccentric shaft 10 into the adjustment hole IB and adjust the position as shown in FIG. By rotating the eccentric shirt 10, the protrusion direction, left and right directions can be adjusted. Then, as shown in FIG. 8(B), the Hesid gap b'1 reference line aK
Match. At this time, the video head 2A is fastened with the screw 3A, and the screw hole of the video head 2A is the screw 3A!
, 9 have a large diameter, it is only necessary to operate the eccentric shaft 10 against this tightening force.

(2) The other video head 2B is also adjusted in the same manner as (2) above.

■Finally, screw the drum clamp 5 onto the head drum 1.
Remove.

However, the conventional method (6), which is operated according to the steps ① to ② above, has the following drawbacks.

First, when an operator rotates the eccentric shaft to align it with the head gap bt-reference line a, the operator must manually perform fine-feeding operations in units of several microns, which requires great skill. Become. Furthermore, this adjustment work must be performed separately for the left and right video heads 2A and 2B.

The second KS adjustment work must be performed while viewing the eyepieces of the optical systems 7A, 7B or the monitor televisions 9A, 9B, which causes severe fatigue for the operator.

Thirdly, in order to fix the head drum 1, this is done by screwing the drum clamp 5, but there is a small gap between the shaft hole IA of the head drum 1 and the outer periphery of the fitting shaft 4A of the mounting table 4. Therefore, no matter how much the drum clamp 5 is tightened, accurate positioning in the radial direction cannot be performed. Therefore, accurate adjustment in the protrusion direction and circumferential direction cannot be performed.

Fourthly, as a result of each of the above-mentioned drawbacks, there is a drawback that variations occur in the products.

The present invention has been made in view of the problems of the prior art described above, and by automatically positioning the video head according to a predetermined program, it is possible to position the video head with high precision, and also to make it possible to position the video head with high precision. An object of the present invention is to provide an automatic video head positioning system that stabilizes the operation of the video head, does not require any skill for the operator, does not cause fatigue, and can be unmanned.

In order to achieve the above object, a first invention according to this application provides a mounting table for mounting head drums on which video heads are provided at least so as to face each other, and a mounting table for mounting head drums on the mounting table. a drum clamp mechanism having a tapered portion that abuts the shaft hole of the head drum for fixing the head drum; and an imaging device arranged facing each other to capture images of each video head of the head drum fixed on the mounting table. A camera, a rotary stage that is rotated by a small angle by a motor, a cam that is installed on the output shaft of the rotary stator and that adjusts the position of the video head by rotating the output shaft, and l!
+ll# device, the control device is configured to match the head gap of the video head imaged by one of the imaging cameras with the head gap of the video head imaged by the other imaging camera as a reference. rotating the motor of the rotary stage to a position;
During this time, the video head is positioned using the cam.

Further, a second invention according to this application provides a mounting table for mounting a tod drum on which the video heads are provided so as to face each other at least, and a mounting table for fixing the head drum on the mounting table. A drum clamp mechanism having a tapered part that abuts against the shaft hole of the head drum, an imaging camera arranged facing each other to take images of each video head of the head drum fixed on the mounting table, and a motor. X
an xy stage that is movable in the direction and the y direction; a rotary stage that is provided on the xy stage and rotates by a minute angle by a motor; and a rotary stage that is provided on the output shaft of the rotary stage (9) and that and a control device, the control device moving the XY stage a predetermined distance in either the X direction or the Y direction to determine the protruding position of the video head. By rotating the rotary stay, the video head is positioned in the protruding direction by the cam, and then the head gap of the video head imaged by one of the imaging cameras is used as a reference. The eccentric direction of the head gap of the video head imaged by the other imaging camera is determined, and the xy stay-zo is fully moved in the eccentric direction, and further, the head gap of the video head imaged by the other imaging camera is matched. The motor of the rotary stage is rotated to the position where the video head is positioned, and during this time the video head is positioned by the AfJF cam.

Embodiments of the present invention will be described in detail below with reference to FIGS. 4 to 6.

In FIG. 1, the video heads 2A and 2B are attached to the screw 3A so as to face each other (lO) to the head drum 1.
, 3B'i, and there is no difference from the prior art in that the video drum 1 is provided with a shaft hole IA located at the shaft center for attaching a rotating shaft.

However, reference numeral 11 designates a base, and 12 designates a mounting frame provided on the base 11. The mounting frame 12 is formed with an escape hole 12A through which a cam 27 (to be described later) moves. 13 is head drum 1'! i- A mounting table on which the mounting table 13 is formed with a fitting shaft 13A that fits into the shaft hole IA and a reference surface 13B, and the bottom side is formed with a shaft 13A facing the video, 2A, 2B direction. Relief grooves 1 and 3C are formed through which a cam 27 (described later) escapes.

14 is a drum clamp mechanism, and in this embodiment, the drum clamp mechanism 14 includes a cylinder 15 fixed to a machine frame (not shown), a piston 16 slidably provided in the cylinder 15, and one end. A piston rod 17 is fixed to the piston 16 and the other end protrudes into the cylinder 15, and the protruding side of the piston rod 17 abuts against one shaft hole of the head drum 1 to fix the head drum 1. ? Part 1
8 is formed.

Next, 19A and 19B are the video heads 2A on the base 11.
, 2B are mounted facing each other in the direction, and are movable in the X direction and the Y direction by manual operation.
0A and 20B are pillars 21A provided on each of the xy stages 19A and 19B.

21B shows the optical system installed in each branch office 2OA, 20B, and 22A, 22B shows an imaging camera installed in each branch office. The video signals captured by the imaging cameras 22A and 22B are input to a control device 28, which will be described later, and are subjected to image processing for each pixel.

Reference numeral 23 indicates an XY stage located within the mounting frame 12 and provided on the base 11, and the XY stage 23 is a Y stage 23Y that moves in the Y direction (in the case of this embodiment, the front-rear direction in the paper). , and an X stage 23X that is provided on the Y stage 23Y and moves in the X direction (in the case of this embodiment, the horizontal direction on the paper surface), and each of the stages 23X and 23Y is operated by stepping motors 24X and 24Y. It is configured so that

Also, a rotary stage is fixedly provided on the X stage 23X of the 25-stage XY stage 23, and the rotary stage 2
5 has a built-in reduction gear (not shown) consisting of a worm and a worm wheel, the worm is provided with a stepping motor 26, and the worm wheel is provided with an output shaft 2.
5A is provided. Incidentally, if the stepping motor 26 has 500 steps and the reduction gear has a reduction ratio of 1/144, the rotation stage 25 rotates for 18 seconds per 1.9 pulses.

Furthermore, 27 is a cam fixed to the output shaft 25A, and the cam 27 is, for example, a notebook-shaped cam, an oval-shaped cam, etc., and is rotated by the rotation stage 25.
0 (13), which is configured to adjust the position of the video heads 2A and 2B. Next, FIG. 2 is a circuit diagram of the device used in FIG. 1, and 28 in the figure indicates a control device; The control device 28 is the processing device 2
9, a storage device 30 for storing programs, etc., and interfaces 31, 32, and 33. And an imaging camera 22A.

22B is connected to the input side of the processing device 29 via the interface 31, and is a stepping motor 24X.

24Y, 26 and the electromagnetic switching valve 34 are connected to the interface 3
2 to the output side of the processing device 29, and are connected to the output side of the processing device 29 through the monitor television sets 35A, 35Bi;l.

It is connected to the output side of the processing device 29 via an interface 33 . In addition, it is a TV monitor.

The ports 35A and 35B may be provided as necessary.

Here, the processing device 29 has an image processing function that determines the white level and black level for each pixel based on a predetermined threshold level based on the video signals input from the imaging cameras 22A and 22B, and a Radial distance between video heads 2A, 2B (video heads 2A, 2B and imaging camera 22A).

The autofocus processing (distance between 14 and 22B)
) Each stepping motor 24X performs arithmetic functions based on the flowchart in FIG.

It has a function of controlling the electromagnetic switching valves 24Y and 26, and a function of displaying images on monitor televisions 35A and 35B.

The present embodiment is configured as described above, and its processing operation will be described with reference to the flow diagram shown in FIG.

First, prior to the positioning operation, the optical system 21A is placed at a position 180 degrees opposite to that of the prior art.

21B accurately. Therefore, as shown in FIG. 4, marking lines 42A are placed at positions 180 degrees opposite each other.

A master gauge 41 having a diameter of 42B is placed on the mounting table 13, and the master gauge 41 is
to be fixed. Next, the optical system 21A is opened by manually operating the XY stages 19A and 19B.

Mark the cross-shaped reference lines 43A and 43B of 21B with the marking line 42A.
, 42B, and adjust the focal length accurately. In addition, the operation at this time is for the monitor television 35A, 3.
You can monitor it with 5B.

Next, add Rad 2A to each video of Head Drum 1.

The position adjustment process of 2B will be described.

First, the head drum 1 is placed on the mounting table 13. This operation is performed manually.

After that, the program start switch of the processing device 29 (
(not shown), the program shown in FIG. 3 starts (step 1).

Then, a clamp signal is output from the processing device 29 to the electromagnetic switching valve 34, and the cylinder 15 of the drum clamp mechanism 14 is
A control fluid, for example compressed air, is supplied to the piston rod 17 to lower the piston 16 together with the piston rod 17 . As a result,
The chi/flat portion 18 abuts against the shaft hole IA of the head drum 1,
Clamp the head drum 1 (Stella f2). During this clamping, as shown in FIG.
is the shaft hole], and there is a circular line contact state over the entire upper surface of A, so even if there is a slight clearance δ between the fitting shaft 13A and the shaft hole IA, the head drum 1 can be accurately positioned and fixed. This makes it possible to increase repeat positioning accuracy during clamping and shorten positioning time, compared to conventional techniques.

Next, the positioning of the dots 2A and 2B in the direction of protrusion into the video will be described with reference to FIG.

In this case, the XY stage 23 is at the center position, and the rotation stage 25 is at the position where the rotation angle is 0 degrees, that is, the head drum 1
(hereinafter, this position will be referred to as the original position), and this original position is represented as a position in FIG. 6, and the cam 27 is located on the original position A.

However, first, the positioning of the video head 2B in the protruding direction (rightward in the plane of the paper in FIG. 6) is performed.

For this reason, the cam 27 that was in the original position AK was moved to the video head 2.
In order to move to a predetermined position B on the back side of B, the processing device 2
9 is stepping motor 24XK for X stage 23X
A predetermined number of pulses is applied. As a result, as the X stage 23X moves, the rotation stage 25
At the same time, the cam 27 moves to position BK and stops (Step 3).

On the other hand, the processing device 29 includes an imaging camera 22A.

A video signal from 22B is input and autofocus processing is performed, and the distance in the protruding direction of the video head 2B at position B is detected from the sharpness of white and black for each pixel (step 4). Then, in the next step 5, it is determined from the sharpness of each pixel whether the video head 2B is at the correct focal position, that is, whether the protruding position is at the correct focal position (step 5). If the judgment in step 5 is ``YES'', proceed to the next step, Step 7; if the judgment is ``No'', the i4 pulse is output to the stepping motor 26, the rotary stage 25 is rotated by a predetermined angle, and the cam 27 is rotated. The video head 2B is displaced in the protruding direction (step 6).The processes of steps 4 to 6 above are executed, and when a YES' determination is made in step 5, the process moves to the next step 7.At this time, the video head 2B is 2B is screw 3A
Since the screw hole of the video head 2B has a larger diameter than the screw 3B, the cam 27 can be rotated against this tightening force.

Next, one video head 2A is positioned in the protruding direction (leftward in the plane of the paper in FIG. 6).

Therefore, in step 7, the X stage 23X is moved from position B to position c-1 on the opposite side. Therefore, K is
This is performed by applying a predetermined number of pulses of /4' to the stepping motor 26 for the stage 23X. Then, in Step 8, the protrusion direction of Do 2A is detected for the video at position C in the same manner as in Step 4, and in the next Step 9, the direction of protrusion is detected in the same manner as in Step 5. Determine whether it is in the correct position. Based on the sharpness of each pixel by focus processing, if the judgment is "YES", go to the next step 11); if the judgment is "NO", the rotation stage 25 is rotated in step 10, and the cam 27 is rotated.
The two video heads are displaced in the projecting direction.

When the video heads 2A, 2B are thus properly positioned in the radial direction and the gap is clearly imaged, the position of the head gap is detected in step 11.12. At the time of this detection, the head drum 1
The video head 2A is fixed as shown in the figure, and the video head 2A is eccentric by an angle α with respect to the axis X+−Xt in the X direction.
is shifted by a distance t1 with respect to the reference line 43A, while the video head 2B is eccentric by an angle β with respect to the axis X, -X, and as a result, in the monitor television 35B, the gap 44B is aligned with the reference line 43B. Assume that the distance t2 is different from the distance t2.

Now, K, who fixes the video head 2B and adjusts the position of the two video heads so that they face the video head 2B, rotates the video head 2A by an angle α+β, that is, a distance of 11+Lz at the monitor television 35A. Just move it.

Therefore, the processing device 29 uses Stella 7'll and the gap f44B of the video head 2B is the distance t! The gap between the two video heads on the Stella F12 is 4.
Read that 4A is shifted by distance t1. and,
In the next step 13, the rotation stage 25 is moved to the position side (fourth
(see figure), i.e. cam 2 in position C.
It is determined whether to move 7 to the position side (or to the position E side).

Now, in the specific example of FIG. 7, it is only necessary to move the cam 27 to the position and move the camera 2A by an angle α+β, so the determination in step 13 is "YES" and the process moves to the next step 14. In step f14, the XY stage 23 is moved to move the cam 27 at position C to position DK.
, moves the rotation stage 25. For this reason, the processing device 29
A predetermined pulse is applied to each step and ping motors 24X, 24Y, and 26. At this time, when the two video heads are at the position shown by the dashed-dotted line 2A' in FIG. 7, K needs to rotate the rotary stage 25 from position C by EK. In step 15, the same process as in step 14 is performed.

(21) Furthermore, in step 16, the video heads 2A, 2B
It is determined whether the gaps 44A and 44B of In this case, since a NO# determination is made in step 16, a pulse is applied from the processing device 29 to the stepping motor 26, and the rotation stage 25 is rotated by minute angles 29, so that the image input from each imaging camera 22A, 22B is Image processing is performed, and the gap 44A has a distance of 11Jftt.
When the gap 44A and the gap 44B are moved by ++1, and the gap 44B is aligned with the gap 44B, it is determined that the gaps 44A and 44B match.

In this way, when a "YES" determination is made in step 16, the stepping motors 24X, 24Y) 2 are activated to return the XY stage 23 and rotation stage 25 to the original position A.
A pulse is applied to 6 (step 18). Then, when these are returned to the original position AK (22), the head drum 1 is moved by the drum clamp mechanism 14.
In order to release the clamp, a clamp release signal is output to the electromagnetic switching valve 34, and the piston rod 17 is lifted upward (step 19). Then, when the drum 1 is removed from the mounting table 13, the entire process ends (step 20).
.

The above is the procedure of the processing operation according to the present embodiment, but in the above-mentioned embodiment, the cam 27 is moved from the original position A in each of the protruding directions B,
After moving the video heads 2A and 2B in the direction C and positioning the video heads 2A and 2B in the protruding direction,
The description has been made assuming that 2B is used for positioning at 180 degrees. However, if there is no need to perform positioning in the protruding direction, that is, if the protruding directions of the dots 2A and 2B have been adjusted in advance for each video, steps 2 to 9 in the flowchart of FIG. can be omitted.

In addition to the above conditions, each video head 2A before adjustment,
When rough assembly is performed in which the two video heads are always shifted in a certain direction with respect to the video head 2B in the initial assembly state of the video head 2B, the angle between the video heads 2A and 2B is always changed as shown in Fig. 7. In the case of an assembly method in which γ is within 1800, the XY stage 23 and stepping motors 24X and 24Y can be omitted. Therefore, in this case, steps 1, 2, 11 and 12 in FIG.
．． Only 16.17.18 and 19.20 are required.

Furthermore, the drum clamp mechanism 14 automatically performs clamping operation (
Step 2), the flange release operation (step 19) has been described, but if the electromagnetic switching valve 34 is a manual switching valve and the clamping operation and the flanging release operation are performed manually, step 2) in Figure 3 is used. 19 can be omitted.

Furthermore, although the stepping motors 24X, 24Y, 26, etc. are taken as examples of motors used in this embodiment, DC
A motor may be used, and in this case, the circuit configuration may be such that the DC motor is controlled by a signal from an encoder. On the other hand, stepping motor 24X
, 24Y, 26, etc., a synchronous motor such as a Selsyn motor may be used.

The automatic video head positioning method according to the present invention has been described in detail above, and since the video head facing the tod drum can be automatically positioned and moved 180 degrees with high precision, the operator can The operator may be an unskilled worker, and a large number of automatic positioning devices can be operated by one worker. In addition, you only need to adjust the position of the other video head while keeping one video head fixed.
Workability can be improved. Furthermore, since the drum clamp mechanism has a structure in which the tapered portion of the drum clamps abuts the shaft hole of the video drum, the positioning accuracy during clamping can be improved and the product can be stabilized.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram of an automatic positioning device used in an embodiment of the present invention, FIG. 2 is a circuit configuration diagram, FIG. 3 is a flow diagram showing automatic positioning processing by the control device, and FIG. 4 is a master r- Figure 5 is an explanatory diagram of the case where the video drum is positioned and fixed by the tapered part of the clamp mechanism, and Figure 6 is the moving position of the cam. An explanatory diagram showing
Fig. 7 is an explanatory diagram of the positioning operation of the video head, Figs. 8 to 10 relate to the prior art, Fig. 8 is an overall configuration diagram of the positioning device according to the prior art, and Fig. 9 is the eyepiece of the optical system. Figure 9 (A) is the state diagram before adjustment, Figure 9 (B) is the state diagram after adjustment, and Figure 10 is the state diagram of the gap seen from above.
The figure is an explanatory diagram showing a method of adjusting the video head. DESCRIPTION OF SYMBOLS 1... Head drum, 2A, 2B... Video head, 11... Base, 12... Mounting frame, 13... Mounting stand, 14... Drum clamp mechanism, 15... Cylinder , 16... Piston, 17... Piston rod,
18...Thenoya department, 21A, 21B...optical system,
22A, 22B...imaging camera, 23...XY stage, 24X, 24Y. 26...Stepping motor, 25...Rotation stage, 27...Cam, 28...Control device, 29...
Processing device, 30...Storage device, 31.32.33...
·interface. (26) Spupco start step Good drum clamp mechanism 14 rB head drum 1t Clamp step: Move the X stay 723X in the direction of position △-B Step ≦ 3 Ketsu 6 Honda I of the video head 2 at position B, direction glaze Output 1% tffiEl meeting Go-238111 (10) 3 figure ≧ Hini-Ko t・

Claims (2)

[Claims] (1) A mounting table for mounting head drums with video heads provided at least so as to face each other, and a taper that abuts against the shaft hole of the head drum in order to fix the head drums on the mounting table. a drum clamp mechanism having a drum clamp mechanism, an imaging cassette disposed facing each other to take images of each video head of the head drum fixed on the mounting table, and a rotation stage rotated by a minute angle by a motor. , a cam provided on the output shaft of the rotary stage and adjusting the position of the video head by rotating the output shaft, and a control device, the control device including a cam that is arranged on the output shaft of the rotary stage, and a control device, the control device being arranged such that the image is captured by one of the imaging cameras. The motor of the rotary stage is rotated until the head gap of the video head imaged by the other imaging camera coincides with the head gap of the video head taken as a reference, and during this time the video head is positioned by the cam. An automatic video head positioning system configured as follows. (2) a mounting table for mounting head drums on which video heads are provided so as to face at least one another;
In order to fix the head drum on the mounting table, there is a drum clamp mechanism having a tapered part that abuts against the shaft hole of the head drum, and a drum clamp mechanism that is connected to each other to take an image of each video head of the head drum fixed on the mounting table. XY that can be moved in the X and Y directions by the imaging camera and motor that are arranged facing each other.
a stage, a rotary stator which is provided on the XY stator and is rotated by a small angle by a motor, and a cam which is provided on the output shaft of the rotary stage and adjusts the position of the video head by rotation of the output shaft. and a control device, the control device moves the xy stage a predetermined distance in either the X direction or the Y direction, determines the protruding position of the video head, and rotates the rotary stage. The cam positions the video head in the protruding direction, and then the video head is imaged by the other imaging camera based on the head gap of the video head imaged by one of the imaging cameras. determine the eccentric direction of the head gap of and move the XY stage in the eccentric direction, further rotate the motor of the rotary stage to a position where the head gap of the video head imaged by the other imaging camera matches, and during this time An automatic video head positioning system configured to position the video head using the cam.