JPS5942366B2 - magnetic recording and reproducing device - Google Patents

Description

Detailed Description of the Invention The present invention uses plungers to bring the head and tape into contact with each other, and to bring the pinch roller into pressure contact with the capstan. Regarding a magnetic recording and reproducing device having a purely electrical configuration that is operated by operating a command switch to run a tape at a constant speed, its purpose is to meet the above 2.
In addition to making it easy to reduce the capacity of the power supply for operating one plunger, the tape does not produce clicks even if the recording operation and stop operation, or the recording operation and recording-stop operation are repeated. The purpose of the present invention is to prevent inconveniences such as a signal being recorded or a signal previously recorded on a tape remaining partially unerased.

In conventional magnetic recording and reproducing devices of this kind, in order to put the device into a playback state or a recording state, a constant tape running command switch, a so-called playback command switch, is operated to bring the head and tape into contact with each other. The plunger and the second plunger for pressing the pinch roller against the capstan are operated simultaneously.

However, in general, the current required for plungers to start operating, the so-called rush current, is several times larger than the current, so-called hold current, that maintains the operating state once the plunger operates, so the above two plungers are operated at the same time. A large amount of current is required for operation, and to cope with this, conventional devices are equipped with a large-capacity power supply. Having to install a large-capacity power source is not desirable in terms of cost, space, or weight, and it also increases power consumption. It did not meet the demands of society. Therefore, the inventors of the present invention focused on shifting the start points of the first, second, and two plungers, and found that it is better to start running the tape after the head and the tape come into contact, resulting in better playback and recording. Taking into consideration the fact that this would be useful in performing the following, we developed a device in which the first plunger is operated when the regeneration command switch is operated, and then the second plunger is operated.

With a device having such a structure, two plungers are not operated at the same time and the rush currents of the two plungers do not overlap, so an abnormally large current is not required and a small capacity power supply is sufficient. This had the advantage of guaranteeing the operation of the plunger. However, if such a structure is adopted, a clicking sound may be recorded on the magnetic tape when the recording operation and stop operation are repeated, or when the recording operation and recording pause operation are repeated, or the signals previously recorded on the tape may be lost. It has been found that a part of the data may remain without being erased, resulting in noise during playback. In other words, if the recording bias oscillator is operated before the tape and the head come into contact with each other, (the inventor of the present invention can operate the recording bias oscillator at the same time as the first plunger is operated to bring the head and tape into contact with each other). (The test was conducted with a configuration in which the recording bias oscillator was operated.) During the process in which the tape and head came into contact with each other, an alternating magnetic field for erasing was developed in the erasing head, and as the tape moved relatively within this alternating magnetic field, The magnetic tape is magnetized in the saturation direction, but just before the head and magnetic tape come into complete contact, a slight positional shift occurs between the head and the tape, so that part of the tape facing the head is not completely magnetically saturated. This has the drawback that a click sound may be produced during playback, or if there is a pre-recorded signal, this may appear as an unerased signal. Therefore, the present invention solves these drawbacks and provides a magnetic recording/reproducing device with excellent performance that can be driven with a small power supply and does not generate clicking sounds. I will explain it together.

First, FIG. 1 shows a first embodiment of the present invention. In the figure, when the recording command switch S1 is closed, the output terminal 2 of the operation command control circuit 1 is at a high level ( A recording command signal (hereinafter referred to as H level) is generated, and this signal is supplied to the recording signal amplifier 3 to put the amplifier 3 into an operating state. Therefore, the recording signal input to the recording signal input terminal 4 is amplified by the amplifier 3, and its output is supplied to the recording head RH. At this time, the switch S4 is closed simultaneously in conjunction with the recording command switch S1 (the plunger is driven by the operation of the recording command switch S1,
This plunger may be used to close the switch S4) to put the recording bias oscillator 5 into an operation standby state. In this state, when the tape constant speed running command switch, so-called reproduction command switch S2, is closed, the first tape constant speed running command signal at H level is outputted to the output terminal 6 of the operation command control circuit 1 as shown in FIG. 2A. This signal is supplied to the first plunger via the drive circuit 7, and the operation of the plunger 8 moves the heads such as RH and EH to the position where they come into contact with the tape T. Ru. At this time, as shown in FIG. 2C, the output terminal 9 of the operation command control circuit 1 receives a second tape at a low level (hereinafter referred to as L level) which is delayed by a certain time t1 from the first tape constant speed running command signal. A constant speed running command signal is output. This signal is then supplied to the second plunger 11 via the second plunger drive circuit 10, and as a result, the plunger 11 operates and the pinch roller P is pressed against the capstan C via the tape T. The rotational force causes the tape T to start running at a constant speed. The second tape constant speed running command signal from the output terminal 9 is supplied to the base of the Npn type transistor 12, which has been in the on state until now.
The recording bias oscillator 5 is turned from ON to OFF to close the switch S4 and to standby.
starts operating and outputs a bias oscillation signal as shown in Figure 2, and at the same time an erase current is supplied to the erase head EH and at the same time a bias current is supplied to the recording head RH via the capacitor 13 to start recording. An action is taken. When the stop command switch S3 is closed in this recording state, the
As shown in the figure, each command signal from the control circuit 1 disappears due to the inversion of the output of the circuit 1, the plungers 8, 11 and the bias oscillator 5 return to a non-operating state, and the apparatus comes to a stopped state.

In the above embodiment, the head is moved to the tape side and brought into contact with each other, but it is also possible to drive the head with a plunger using a tape shifter or the like to move the head to the side where the tape is fixed and bring the two into contact. Also good.

Further, in the above embodiment, the transistor 12 is turned off by the second tape constant speed running command signal that drives the second plunger 11, but the first plunger 8 is activated by the first tape constant speed running command signal. After that, a dedicated control signal may be output from the control circuit 1 before the second plunger 11 is operated, thereby turning off the transistor 12. Of course, transistor 12
It is also possible to operate the recording bias oscillator 5 when the oscillator is on. Next, FIG. 3 shows a second embodiment of the present invention, which utilizes the configuration of the first embodiment as is, but adds a temporary stop function to it. Therefore, the same components as those in FIG. , the recording bias oscillator 5 enters the operation standby state, and then the tape constant speed running command switch S2
With the operation, the first plunger 8 is operated to bring the head and tape into contact with each other, and after a certain period of time, the second plunger 11 is operated and the pinch roller P is pressed against the capstan C. The recording bias oscillator 5 becomes operational and a recording operation is started. When the temporary stop switch S5 is operated in this recording state, only the command signal at the output end 9 is reversed and disappears, and only the second plunger 11 is deactivated. However, at the same time, an L level temporary stop command signal is generated from the output terminal 14 and is supplied to the base of the transistor 12 via the OR circuit 15.
Since the recording bias oscillator 5 is kept in an off state, the recording bias oscillator 5 remains in an operating state. As described above, the bias oscillator 5 operates in both the recording state and the pause state. When attempting to resume recording, the tape constant speed running command switch S2 may be closed again and the second plunger 11 may be operated. In the above two embodiments, each command switch S1~
S3 and S5 are of the normally open type, and when these switches are instantaneously closed, the command is stored in the operation command control circuit 1, and the switch S4 is linked to the operation of the recording command switch S4. It is turned on, maintained in that state, and returned to the off state by operating the stop command switch S3.

As explained above, the magnetic recording/reproducing apparatus of the present invention provides the following effects.

1 After the first plunger works to bring the head and tape into contact with each other, the second plunger works to press the pinch roller against the capstan and start running the tape at a constant speed. A small power supply can be used to drive the plunger, and since the recording bias oscillator starts operating after the head and tape come into contact with each other, the click noise recorded on the tape when recording starts is reduced. be done.

2. Bias oscillation starts after the head and tape come into contact with each other, so the rise of the bias oscillation signal can be made steeper, and even if the two operations of recording and stopping are repeated, the signal recorded in advance on the tape will not be lost. This reduces the possibility that the data will be left unerased.

3. Even if the recording operation and the pause operation in the recording state are repeated, the recording bias oscillator is always operating during the above two operations, so no click sound is recorded when switching between the two operations.

4. Furthermore, even if the recording operation and the pause operation in the recording state are repeated, the signal previously recorded on the tape will not be left unerased.

5 By performing a pause operation at the start of recording, the head can wait with the head in contact with the tape and the recording bias oscillator is activated, so that recording can start smoothly and smoothly. can.

[Brief explanation of the drawing]

FIG. 1 is a circuit configuration diagram showing a first embodiment of the device of the present invention, FIG.

Claims (1)

[Scope of Claims] 1. A recording command switch, a tape constant speed running command switch, and a first plunger that is operated by operation of the tape constant speed running switch to bring the head and tape into contact with each other;
A second plunger that operates after a fixed time delay from the time of operation of the first plunger to press the pinch roller against the capstan, and a first plunger that operates by operating the recording command switch to place the recording bias oscillator in an operation standby state. and a second control means that operates after the first plunger is operated by the operation of the tape constant speed running command switch and puts the recording bias oscillator in an operation standby state, A magnetic recording/reproducing device configured such that a recording bias oscillator is brought into operation when two control means operate together. 2. A recording command switch, a tape constant speed running command switch, a pause command switch, a first plunger that is operated by the operation of the tape constant speed running command switch and brings the head and tape into contact with each other, and this second plunger. a second plunger that operates with a certain time delay from the time of operation of the plunger and presses the pinch roller against the capstan;
, a release means for releasing the operation of only the second plunger of the two plungers, a first control means that is activated by operation of the recording command switch and puts the recording bias oscillator in an operation standby state, A second plunger that operates after the first plunger is activated by operation of the speed command switch to place the recording bias oscillator in an operation standby state.
and a third control means that is activated by the operation of the temporary stop command switch to place the recording bias oscillator in an operation standby state, the control means being controlled by the first and second control means or the first and third control means. A magnetic recording/reproducing device configured such that a recording bias oscillator is activated when the means operate together.