JPH0633533Y2 - Azimuth adjustment device for magnetic head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION << Industrial Application Field >> The present invention relates to an azimuth adjusting device for a magnetic head in a tape recorder, and more particularly to a device for manually adjusting the magnetic head.

<< Prior Art >> Conventionally, for a mechanism for manually adjusting the azimuth of a magnetic head, see, for example, JP-A-60-192126 filed by the present applicant. This mechanism is also applicable to the azimuth adjustment of the reproducing head in a so-called three-head type tape recorder having an erasing head, a recording head and a reproducing head. In this case, the operator can adjust the azimuth of the reproducing head for each tape to be heard according to the sense of hearing, and thus the tape reproduction can be performed without the sound quality deterioration due to the azimuth shift.

<< Problems to be Solved by the Invention >> However, in such a mechanism, it is necessary to return the azimuth of the reproducing head to the reference position which is the same position as the azimuth of the recording head during recording. That is, when the azimuth of the reproducing head during recording is different from the azimuth of the recording head, the direct recording is not affected, but the reproduced sound at the time of after-monitoring, which is a feature of the three-head tape recorder, deteriorates.

In order to eliminate such a drawback, for example, the azimuth adjusting mechanism of the reproducing head is configured so that the azimuth of the reproducing head is adjusted by a manually operated switch and a motor controlled by this switch. It is possible to forcibly return the azimuth of the reproducing head adjusted by to the reference position during recording.

However, in this configuration, a mechanism for adjusting the azimuth requires a component such as a motor, which is disadvantageous in terms of cost.

<< Means for Solving Problems >> An operating knob that is operated to adjust the azimuth of a magnetic head in a tape recorder, and a transmission mechanism that displaces in response to the operation of the operating knob and changes the azimuth position of the magnetic head. And a detection means for detecting a substantially intermediate position of the operation knob in a required operation range, a display means, and a display control means for responding to the detection means and controlling the display means.

<< Operation >> The display means has different display states at the substantially intermediate position and the non-intermediate position of the operation knob. Further, in the reproducing mode of the tape recorder, the display means has the first state change, and in the recording mode, the display means has the second state change different from the first state change.

<Embodiment> FIGS. 1 and 2 are a front view and a plan view of an azimuth adjusting device according to the present invention, in which a tape recorder is in a stop mode, and the azimuth of a reproducing head matches the azimuth of a recording head. It shows the state of taking a position. Note that the front panel of the tape recorder is omitted in FIG.

The operation knob 2 that protrudes from the front panel 1 of the tape recorder and is rotated by the operator is ± 15 on the chassis 3.
It is integrated with a rotary cam 4 which is rotatably supported at 0 degrees. The rotary cam 4 has a cam surface 5 whose radius changes linearly in the rotation direction, and 72 cams along the entire circumference of the cam surface 5 so that a click feeling can be obtained when the operator operates the operation knob 2. A serration 6 having teeth and a V-shaped recess 7 formed on the outer circumference are formed, respectively. Here, the center position of the recess 7 in the circumferential direction is configured to coincide with the center position of the groove of the serration 6.

A first arm 12 pivotally supported by the chassis 3 and biased clockwise by a torsion spring 11 in FIG.
Has a driven pin 13 formed at one end thereof in contact with the cam surface 5 of the rotary cam 4. Pin 2 planted in chassis 3
The slide plate 14 which is movable in the direction A-B in FIG. 1 which is horizontal with respect to the chassis 3 by loosely fitting the long holes 29 in the holes 8 and 28 has the other end of the arm 12 at one end thereof. The ends are engaged.

In the illustrated state, the driven pin 13 is at the center position of the cam surface 5 in the rotation direction. Therefore, the first arm
The slide plate 14 and the slide plate 14 are located at the center positions in the moving range.

Head base 15 that moves in the direction C in the figure during playback mode
The second arm 16 is rotatably supported by the bent portion 36 of the second arm 16, and the long hole 17 formed at one end of the arm 16 is bent at the other end of the slide plate 14. A pin 19 is inserted in the portion 18 and is parallel to the moving direction of the head base 15. An azimuth adjusting screw 20 is screwed onto the other end of the second arm 16. Here, the reproducing head mounting plate 22 on which the reproducing head 21 is mounted is mounted on the head base 15 by a spring (not shown).
The tip of the azimuth adjusting screw 20 supports one end of the azimuth adjusting screw 20, and the other end of the azimuth adjusting screw 20 is supported by two protrusions 23, 23 provided on the head base 15. Also,
The head base 15 supports the recording head 27 mounted on the recording head mounting plate 26.

Here, when the operation knob 2 is rotated ± 150 degrees,
The reproducing head 21 rotates ± 50 minutes. Further, the azimuth adjusting screw 20 is such that the azimuth of the reproducing head 21 is the recording head when the rotary cam 4 is at an intermediate position in its rotation range.
It is used when adjusting when assembling the tape recorder so that the reference position matches the azimuth of 27.

The leaf spring 30 whose one end is fixed to the chassis 3 has two other ends.
While being branched into two, bending members 31 and 32 are formed in each. One of the bent portions 31 enters the concave member 7 formed on the outer periphery of the rotary cam 4, and the other 32 contacts the serration 6 formed on the rotary cam 4. The tip 35 of one of the bent portions 31 is in contact with the actuating portion 34 of the switch 33 fixed to the chassis 3, and the bent portion 31 causes the rotating cam 4 to move.
In the state shown in the drawing, which engages with the recess 7 of the switch 33, the switch 33
Is off. Also, when the operation knob 2 is rotated to adjust the azimuth of the reproducing head 21, the bending portion 31
Is displaced from the concave portion 7 to bend as shown by the dotted line in FIG. 1, and the switch 33 is turned on.

The switch 33 is connected to a control circuit 40 including a microcomputer and controls the display state of an azimuth indicator 41 provided on the front panel 1 of the tape recorder based on the state of the switch 33 and the operating state of the tape recorder.
The azimuth indicator 41 is a two-color light emitting type that can be in either a light-off state or a display state of red or green light emission.
This is an LED, and when the tape recorder is in the reproduction mode and the switch 33 is in the off state, it is in a green lighting state, and in the on state, it is a non-lighting state. In addition, in the recording mode and the recording standby mode of the tape recorder, it is controlled so that the switch 33 is in the green lighting state when the switch 33 is in the off state and in the red lighting state when the switch 33 is in the on state. Further, when the tape recorder is in a mode other than the above-mentioned modes, the azimuth indicator 41 is turned off regardless of the state of the switch.

The operation of the above configuration will be described.

In the state shown in the figure, the tape recorder has a head base 15
Is in the stop mode located at the bottom of FIG. Further, since the rotary cam 4 is at the intermediate position in its rotation range, the reproducing head 21 takes the reference position where its azimuth coincides with that of the recording head 27. In this state,
The azimuth indicator 41 is off.

When the tape recorder enters the reproduction mode, the required drive mechanism moves the head base 15 in the direction C of FIG. At this time, the second arm 16 also moves, but the slide plate 14
Pin 19 parallel to the moving direction of the head base 15
However, by sliding inside the long hole 17 of the arm 16, the movement of the head base 15 does not affect the azimuth position of the reproducing head 21.

Also, when the tape recorder enters the playback mode, the azimuth indicator 41 goes from the off state to the green light emitting state,
When the operator rotates the operation knob 2 in the clockwise direction in FIG. 1, for example, in order to obtain the best reproduced sound,
The recess 7 of the rotating cam 4 is disengaged from the bent portion 31 of the leaf spring 30. Therefore, the switch 33 is turned on and the azimuth indicator 41 is turned off. At this time, the first arm 12 is rotated clockwise by the torsion spring 11 so that the driven pin 13 provided at one end of the first arm 12 follows the cam surface 5.
Therefore, the slide plate 14 moves in the direction A in the figure, and rotates the second arm 16 about the shaft 25 in the counterclockwise direction in FIG. Along with this rotation, the azimuth adjusting screw 20 screwed to the other end of the second arm 16 also rotates about the shaft 25 in the counterclockwise direction in FIG. Therefore, the reproducing head mounting plate 22 that is in contact with the tip of the azimuth adjusting screw 20 is rotated clockwise around the contact point of the protrusion 23 provided on the head base 15, so that the reproducing head 21 is the same. Turn clockwise to adjust azimuth.

When the operator turns the operation knob 2 counterclockwise,
Contrary to the above, the reproducing head 21 is rotated counterclockwise.

Here, in the reproduction mode, the azimuth indicator 41 emits green light at the reference position of the reproduction head 21 and turns off at other positions, so that the azimuth of the tape currently being reproduced is the reference. It is possible to immediately determine whether or not the position is deviated.

When the tape recorder is set to the recording mode from the stop mode in the illustrated state, the head base 15 is moved in the C direction in the figure as described above. In this mode, when the rotary cam 4 is located at the intermediate position, the azimuth indicator 41 is in the green lighting state, but in other positions, it is in the red lighting state.

In a general tape cassette in which the shell is not greatly deformed, by placing the operation knob 2 at the intermediate position,
After-monitoring that is almost unaffected by azimuth is performed. However, after reproducing the tape cassette whose shell is deformed or the tape cassette recorded by the tape recorder whose recording azimuth is deviated with the azimuth of the reproducing head 21 adjusted by rotating the operation knob 2 from the intermediate position, the tape is deformed. It is possible to try to record using a tape cassette that is not available. At this time, in a state where the operation knob 2 is kept rotated and is not returned to the intermediate position, the after-monitor sound during recording is deteriorated by the influence of azimuth, so that the operator deteriorates the tape used or uses it. There is a possibility of erroneously determining that this is due to a mistake in setting the bias or equalizer set for each tape.

However, in the recording mode, when the operation knob 2 is not at the intermediate position, the azimuth indicator 41 is in a red light emitting state, so that the operator immediately recognizes that the azimuth of the reproducing head 21 is not at the reference position. , Operation knob 2
Can be returned to its intermediate position.

In the recording standby mode state, similarly to the recording mode, the azimuth indicator 41 emits green light when the operation knob 2 is at the intermediate position, and red light emission state when the operation knob 2 is not at the intermediate position. Moreover, it is possible to easily set the azimuth of the reproducing head 21 to the reference position.

Therefore, in the above-described embodiment, when the reproducing head 21 is in the active state as in the reproducing mode and the recording mode, and in the active preparation state as in the recording standby mode, the reproducing head 21 is When the azimuth is in the reference position, the azimuth indicator will appear in any mode.
41 emits green light, indicating that the reproducing head 21 is at the reference position. Also, in the recording mode and recording standby mode,
When the azimuth of the reproducing head 21 is not at the reference position, the azimuth indicator 41 emits red light and the operator is given a control knob 2
Is returned to the intermediate position.

Due to its mechanism, the concave portion of the rotary cam 4 provided to detect the intermediate position in the rotation range of the operation knob 2 cooperates with the bent portion 31 of the leaf spring 30 to prevent the operation knob 2 from rotating. It causes a click feeling. This clicking sensation is generated when the bent portion 31 of the leaf spring 30 is drawn into the recess 7 formed in the rotary cam 4, and in the azimuth adjusting device of the present invention, the click position is centered around the intermediate position of the operation knob 2. It occurs over ± 15 degrees. The rotation range where this click feeling occurs is a dead zone during azimuth adjustment,
It becomes impossible for the reproducing head 21 to adjust about ± 5 minutes from the reference position. Converting this unadjustable range to the deterioration of the frequency characteristics due to the azimuth shift, the loss of 2 dB cannot be adjusted at 20 KHz.

However, the serration 6 provided on the rotary cam 4
Holds the concave portion 7 formed in the rotary cam 4 by the bent portion 31 of the leaf spring 30 so as not to be pulled in. Therefore, in the above-described embodiment, over the entire rotation range of the operation knob 2,
It can be operated in units of 5 degrees, and the azimuth of the reproducing head 21 can be adjusted in units of about 1.7 minutes. In addition, since a click due to serration occurs over the entire rotation range of the operation knob 2, a good operation feeling can be obtained.

The present invention is not limited to the above-described embodiment, but can be applied to, for example, a so-called recording / playback head azimuth adjusting device in which a recording head and a reproducing head are combined. In this case, the recording / playback head whose azimuth was adjusted during playback can be easily returned to the reference position by the azimuth indicator during recording, and erroneous recording due to the azimuth of the recording / playback head deviating from the reference position during recording can be avoided. It is possible to inform the operator.

In addition, two monochromatic LEDs are used as azimuth indicators.
In the above embodiment, the azimuth indicators can be in three states of off, green emission and red emission. However, the present invention is not limited to this. It is possible to take one of the two states, and various modes are possible without departing from the spirit of the present invention.

<Effect of the Invention> As described above, according to the present invention, it is possible to easily identify whether or not the operation knob for adjusting the azimuth of the magnetic head is at the intermediate position. An azimuth adjusting device can be provided.

Furthermore, according to the present invention, in the recording mode and the playback mode,
Since the display change of the azimuth indicator due to the change of the position of the operation knob is different, it is possible to prompt the operator to return the operation knob to the intermediate position in the recording mode.Therefore, the tape recorder must be equipped with a manual azimuth adjustment device. It is possible to reduce operation mistakes due to.

[Brief description of drawings]

1 and 2 show a front view and a plan view of an azimuth adjusting device according to the present invention. 2 ... Operation knob, 3 ... Chassis, 4 ... Rotating cam, 5 ... Cam surface, 6 ... Serration, 7 ... Recess, 12, 16 ... Arm, 13
... driven pin, 14 ... slide plate, 15 ... head base, 20 ...
Azimuth adjustment screw, 21 ... Play head, 27 ... Recording head,
30 ... Leaf spring, 31, 32 ... Bend part, 33 ... Switch, 34 ... Actuating part, 40 ... Control circuit, 41 ... Azimuth indicator.

Claims (2)

[Scope of utility model registration request] 1. An operation knob operated to adjust the azimuth of a magnetic head in a tape recorder, a transmission mechanism that is displaced in response to the operation of the operation knob, and changes the azimuth position of the magnetic head, Detection means for detecting a substantially intermediate position in the required operation range of the operation knob,
Display means, and display control means for responding to the detection means in any mode of the tape recorder and controlling the display means to have different display states at the substantially intermediate position and the non-intermediate position of the operation knob. An azimuth adjusting device for a magnetic head, which is provided. 2. The display control means responds to the change of the operation knob from the intermediate position to the non-intermediate position so that the display means changes to the first state in the reproduction mode of the tape recorder. The azimuth adjusting device for a magnetic head according to claim 1, wherein in the recording mode, the display means is controlled such that the display means has a second state change different from the first state change.