JPS5940317A - Detector for head using time of recorder - Google Patents

Abstract

PURPOSE:To measure accurately the using time of a magnetic head and to display it, by providing a memory which stores the contents of a counter that integrates the pulses of a pulse generator driven when a recorder is set in a reproduction mode and a display which performs display by the output signal given from the memory. CONSTITUTION:An arithmetic circuit 2 delivers a prescribed level of DC control voltage as long as a recorder is set in a reproduction mode and not in a pause mode. The output of the DC control voltage is supplied to a pulse generator 3, and meanwhile a pulse of a fixed width is delivered and supplied to a counter 4. The pulses supplied to the counter 4 are counted and stored with integration to a memory 5 in the form of a digital quantity. At the same time, a prescribed quantity of the wear-resistant lifetime of a head, etc. is written to a memory 6. A comparator 8 compares the contents between memories 5 and 6, and the contents of the memory 5 are delivered when coincidence is obtained from the comparison. Furthermore, the contents of the memory 5 are delivered when necessary by turning on a manual switch 9 and then supplied to a display driving circuit 10.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a usage time detector for a magnetic head of a recording device that uses a recording medium using a magnetic material, such as a magnetic tape.

In general, unlike recording heads and erasing heads, which are automatically demagnetized by recording bias, magnetic heads that are in contact with a sliding magnetic material, especially playback heads, are not initially magnetized, but after long-term use. It becomes magnetic. This is called magnetization, and when a magnetic head is magnetized, it causes an increase in noise and attenuation of high frequencies during recording, and attenuation of high frequencies and S
Magnetized heads must be demagnetized to prevent phenomena such as deterioration of C and erasure of recorded records. Although there are materials that are difficult to magnetize, they cannot be used practically in magnetic heads due to performance and cost considerations. Therefore, it is difficult to avoid magnetization of the magnetic head, and it is generally difficult to know the state of magnetization of the head, so the user usually relies on his or her intuition to make a decision. For this reason, unnecessary degaussing operations may be performed, or portions of records may be erased due to magnetization. Magnetization is related to the usage time of the head, so if you memorize the usage time, you can know when to demagnetize, but in reality, it is not possible to play, stop, record, etc.
Since fast forwarding and the like are repeated arbitrarily, it is difficult to accurately detect the usage time. In addition, with the exception of some materials, the cap length, head tip shape, etc. of magnetic heads change before the recording device itself due to wear, making it impossible to maintain full initial performance and requiring replacement. It is difficult to make a W judgment.

The present invention has been made in view of the various drawbacks as described above, and an object of the present invention is to provide a detector that can accurately measure and display the usage time of a magnetic head. The details will be explained below using an embodiment shown in FIG.

This embodiment uses a full logic control deck to detect and display the sound of the playback usage time of the head. 2), the predetermined 1 corresponds to each state of playback, stop, and pause.
A 1st current voltage is output. In the arithmetic circuit (2), a predetermined DC control voltage is output only when the function of the main body is in the regeneration state and not in a paused state. This is because if the head is temporarily stopped, it cannot be said that the head is actually used mechanically or electromagnetically. The above DC control voltage is input to the pulse generator (3), and the pulse generator (
3) outputs a pulse with a constant width while the DC control voltage is manually applied, and this pulse is input to the counter (4). The counter (4) manually counts the pulses (when used for other purposes, for example, when performing long-term measurements such as measuring the wear resistance life of a head, it is recommended to divide the frequency after counting if necessary). The data is accumulated and stored as a digital amount in the first memo IJ (5) (for example, RAM).

This stored digital amount corresponds to the usage time up to now. Also the second note January 6) (e.g. R
A predetermined amount is written in advance in another memory prepared as OM. (This is sufficient as long as the time requires maintenance of the head.) The first memory (5) and the second memory (6) are connected to a backup battery (the contents are retained even if the power to the main unit is turned off due to power).A comparator (8)
Now, compare the contents of the first memo (January 5) and the contents of the second memory (6), and find that the contents of the first memory (5) and the contents of M2's memo (January 6) are the same. When they become equal, the contents of the first memory (5) are output. Further, if necessary, by turning on the manual switch (9), the contents of the first memory (5), that is, digital information representing the usage time of the head up to the present time, can be transferred to the first memory (5).
is output from the memory (5). 1st memo above January 5th
) enters the display drive circuit α0).

In the display drive circuit GO), LEI), L(]J
, is converted into a current that can drive a speaker, etc., and the user is informed that the usage time of the head has reached a predetermined value by emitting light on the display αD, displaying numbers, or sounding. Furthermore, once the maintenance of the head is completed, the first memory (5)
The contents of are reset to all 0 (zero) and the above process is repeated.

As described above, by using the detector according to the present invention, after a certain period of time has elapsed, the user is prompted to maintain the head by displaying the time using numbers such as an LED or LCD, flashing a lamp, or outputting a sound. You can notify what is necessary, and if necessary, use the manual switch (9) above.
)'t By turning it on, you can also know how long the head is being used in the housing at that time.

As another example of application, it is possible to detect and display not only the usage time of the head, but also the usage time of equipment with consumable parts such as motors by using all the detectors of the present invention. shall be. Also, 1 as above
Not just one value, but multiple values in the second memory (6)
It is also possible to make the display αυ display a desired display each time the contents of the first memory (5) become equal to the contents of the second memory (6).

Furthermore, the L of the electronic counter of the tape deck is displayed on the above display aυ.
It can be constructed at low cost by using ED, PL tubes, etc.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention. (1) Mechanism control circuit (2) Arithmetic circuit (3)
Pulse generator (4) Counter (5) First memory (6) Second memory (ka) Backup battery (8) Comparator (9) Manual switch 00
) Display drive circuit 0D Display

Claims (1)

[Claims] A mechanism control circuit that causes the recording device to perform all predetermined operations; an arithmetic circuit that determines whether or not the recording device is in a reproducing state based on a signal from the mechanism control circuit; a pulse generator, a second memory for integrating all the pulses from the pulse generator (a counter and a second memory for storing the contents from the counter), a second memory for storing a predetermined value, and the first memory for storing a predetermined value. a comparator that compares the entire contents of the memory and the second memory; a display drive circuit that performs signal conversion based on the output signal from the first memory; The indicator and all the features to do! ! A head use time detector of a recording device, which is characterized by: