JP3089188B2 - Magnetic head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head of a magnetic recording / reproducing apparatus for reading and / or writing signals from / to a magnetic medium, and in particular, to electrically detect the life (wear limit) of the head. The present invention relates to a magnetic head having a function.

[0002]

2. Description of the Related Art In recent years, magnetic card readers and magnetic tape recorders for recording / reproducing information on magnetic stripes such as credit cards and cash cards, and magnetic stripes of prepaid cards such as telephone cards and orange cards. Are widely spread. FIG. 10A shows an example of a magnetic head used in such a magnetic recording / reproducing apparatus. This magnetic head has at least a pair of magnetic cores opposed to each other with a magnetic gap (gap spacer) 107 interposed therebetween. 103,1
For example, one magnetic core 103 has a reproducing coil 105 wound around it, and the other magnetic core 104 has a recording coil 106 wound around it. This is for recording and / or reproducing signals on the medium 2. The magnetic core 1 of the magnetic head
03 and 104 are usually used to shield electromagnetic noise.
The periphery is covered with a shield case 110. Between the shield case 110 and the magnetic cores 103 and 104, there is provided a frame material or a space material 111 made of a non-magnetic material such as resin for fixing the two and also preventing a magnetic short circuit.

In a magnetic head having a structure as shown in FIG. 10A, a pair of magnetic cores 103 and 104 are used as a magnetic recording / reproducing unit.
There is a portion (referred to as a head portion) which is abutted from both sides with the magnetic medium 2 in contact with the head portion.
07, both magnetic cores 103 and 104 will be worn. For this reason, the initial depth of the head portion is d, but as shown in FIG. 10B, the head becomes thinner due to abrasion. When the depth exceeds the limit of abrasion (that is, the life of the magnetic head) d ', recording / reproduction failure occurs. Cause Since recording / reproduction failure due to the life of the magnetic head occurs suddenly, in the case of a magnetic recording / reproduction device such as a card reader, there is a possibility that information on a customer's magnetic card such as a credit card or a cash card may be destroyed. In some cases, the card cannot be used, which may cause a lot of trouble. For this reason, it is necessary to predict this before the magnetic head reaches the end of its life (wear limit) and replace the magnetic head.

Therefore, conventionally, as a guide for determining the replacement time based on the life of the magnetic head, the number of uses (use period) up to the life is determined by converting market results into data, and the life time is determined in advance. As shown in FIG. 10B, the depth d ′ reduced by wear is estimated by observing or measuring the wear width W of the head portion to predict the life limit, and the impedance of the magnetic head is changed. In addition, there is a method of periodically measuring a change in inductance or a inductance, and estimating a life limit from a change in characteristics of a magnetic circuit or an electric circuit.

[0005]

However, according to the above methods, there is a great deal of variation among products, and there is a possibility that the head will reach the end of its life before replacement. In addition, there is a problem that replacement may be performed well before an appropriate replacement time, and there is a problem that a component replacement cost is required. Also, in the method of predicting the life from the wear width of the magnetic head as described above, it is difficult to know the wear limit accurately, and it is difficult to predict by measuring the wear width. In addition, it is necessary to periodically observe and measure the magnetic head, which is difficult. Also,
In the method of estimating the life limit from the change in the characteristics of the magnetic circuit and the electric circuit as described above, it is necessary to measure the initial (immediately after head replacement) data and store it in a nonvolatile memory or the like.
In addition, since it is necessary to periodically measure and compare data, it is troublesome and management is difficult. As mentioned above,
Conventionally, the wear limit (life) of the head portion of the magnetic head cannot be known accurately, and the magnetic head cannot be replaced at an appropriate time.

The present invention has been made in view of the above circumstances, and has as its object to provide a magnetic head provided with a life detecting means capable of electrically and accurately knowing the wear limit of the head portion.

[0007]

In order to achieve the above object, according to the present invention, a head portion comprising at least a pair of magnetic cores opposed to each other with a magnetic gap therebetween is in sliding contact with a magnetic medium to record and / or record signals. Alternatively, in a magnetic head that performs reproduction, a life detecting unit that is cut by abrasion of the head at a position shallower than the effective depth of the magnetic gap from the sliding surface of the magnetic medium is provided on a constituent member of the head, and the life detecting is performed. The configuration is such that the cutting due to wear of the portion is electrically detected to detect the life (wear limit) of the head portion. Below
More specific means will be described.

According to the first aspect of the present invention, the magnetic gap is sandwiched.
At least one pair of magnetic cores
In sliding contact with the magnetic medium at the head section to record and / or read signals.
In the magnetic head for producing a magnetic head, a gap spacer sandwiched between the pair of magnetic cores to form the magnetic gap is formed of a conductive material having an insulating layer provided on both surfaces, and the gap spacer is provided with a magnetic gap. A life detecting unit that is cut by abrasion of the head unit at a position shallower than the effective depth from the medium sliding contact surface is provided, and a life detecting circuit is connected to the gap spacer. The structure is such that the cutting due to abrasion is detected and the life of the head portion (wear limit) is detected.

[0009] In the present invention of claim 2, in the magnetic head according to claim 1, and the life detection unit and structure in which a plurality of positions of the gap spacer.

According to the third aspect of the invention, the magnetic gap is sandwiched.
At least one pair of magnetic cores
In sliding contact with the magnetic medium at the head section to record and / or read signals.
At least one magnetic core is a magnetic core having a laminated structure in which a plurality of magnetic cores are laminated, and a laminated spacer laminated between the magnetic cores and having an interval between the cores is insulated on both sides. The laminated spacer is provided with a life detecting unit which is cut by abrasion of a head unit at a position shallower than an effective depth of the magnetic gap from a sliding surface of the magnetic medium, and the laminated spacer is formed on the laminated spacer. A life detecting circuit is connected to the spacer, and the life detecting circuit detects a cut due to wear of the life detecting section to detect the life (wear limit) of the head section.

According to a fourth aspect of the present invention, in the magnetic head according to the third aspect , the magnetic core having a laminated structure on one side comprises a narrow reproducing core and side cores laminated on both sides of the reproducing core via a laminated spacer, The other magnetic core is a wide recording core having a width obtained by adding a reproducing core width and a side core width, and an insulating layer is provided on both sides of the laminated spacer laminated between the reproducing core and the side core and having a space between the cores. The laminated spacer is provided with the life detecting section.

According to a fifth aspect of the present invention, in the magnetic head according to the third or fourth aspect , the life detecting section is provided at a plurality of portions of the laminated spacer or at a plurality of laminated spacers.

As another configuration example different from the above configuration, signals are recorded and / or reproduced by slidingly contacting a magnetic medium with a head portion composed of at least a pair of magnetic cores opposed to each other with a magnetic gap therebetween. The magnetic head has a shield case that covers the magnetic core except for the periphery of the magnetic gap, and has a side spacer that is arranged between the magnetic core and the shield case and is spaced between the magnetic core and the shield case. The side spacer is formed of a conductive material having an insulating layer on both sides, and the side spacer is cut by a wear of a magnetic head at a position shallower than an effective depth of the magnetic gap from a sliding surface of the magnetic medium. A life detecting circuit is provided, a life detecting circuit is connected to the side spacer, and the life detecting circuit detects a cut due to wear of the life detecting unit. There is a structure for detecting the life of the head portion (wear limit) Te.

In the magnetic head having this structure, the life detecting portion may be provided at a plurality of positions on the side spacer.

[0015]

According to the magnetic head of the present invention, a gap spacer which is sandwiched between a pair of magnetic cores to form a magnetic gap is provided.
2) A laminated spacer laminated between magnetic cores of a magnetic core having a laminated structure and provided with an interval between the cores.
Any one of 4, 5) is formed of a conductive material having an insulating layer on both surfaces, and the constituent member is formed by abrasion of the head at a position shallower than the effective depth of the magnetic gap from the sliding surface of the magnetic medium. A life detecting section to be cut is provided, and the life detecting section is electrically detected to be cut due to abrasion. That is, a life detecting circuit is connected to the component member, and the life detecting circuit cuts the life detecting section due to abrasion ( (Electric circuit cut) is detected to detect the life (wear limit) of the head, so that the head can reach the wear limit (life) immediately before the head reaches the wear limit (life) without regular observation. The magnetic head can be electrically detected, and the magnetic head can be replaced before the end of its life, so that a trouble due to the life of the magnetic head in use can be prevented.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments. (Configuration Example 1) First, a description will be given of an embodiment according to claim 1, 2. 1A and 1B are explanatory diagrams of a configuration of a magnetic head according to an embodiment of the present invention. FIG. 1A is a diagram illustrating a cross section in a direction perpendicular to a magnetic gap of the magnetic head, and FIG. 1B is a diagram illustrating a magnetic head illustrated in FIG. A
A diagram showing an example of connection with a cross section of the A line and a life detecting circuit,
(C) and (d) are a plan view and a sectional view of a gap spacer which is one of the features of the present invention. The magnetic head 1 shown in FIG. 1 has a basic configuration similar to that of the magnetic head shown in FIG. 10, and includes at least a pair of magnetic cores 3 and 4 opposed to each other with a magnetic gap (gap spacer 7) interposed therebetween. The head portion slides on the magnetic medium 2 to record a signal and / or
Or, it performs playback. The illustration of a shield case that covers the periphery of the magnetic core is omitted.

The magnetic cores 3 and 4 each have a single-piece construction made of a magnetic material such as permalloy, sendust, or ferrite.
Alternatively, the magnetic cores 3 and 4 are made of a laminated metal magnetic material. The coils 5 and 6 are wound around the body of each of the magnetic cores 3 and 4, and the coils 5 and 6 are connected to the electrode terminals 8a and 8b. 9
They are connected to a reproducing circuit and a recording circuit (not shown) via a and b. The coils 5 and 6 are used for reproduction (read) and recording (write). However, when used for only reproduction or recording, the coils need only be wound on one core. .

In this embodiment, a gap spacer 7 sandwiched between a pair of magnetic cores 3 and 4 to form a magnetic gap.
Is formed of a non-magnetic conductive material (copper, phosphor bronze, etc.) 7a having an insulating layer 7b on both sides, and the gap spacer 7 has a magnetic gap smaller than the effective depth d from the sliding surface of the magnetic medium 2. A slit-shaped life detecting section (an electric path having a width h smaller than the effective depth d) 11 which is cut at a shallow position h (<d) due to wear of the head section is provided. Both electrodes of the conductive material 7a of the gap spacer 7 provided with the life detecting section 11 are connected to the electrode terminals 10 by lead wires.
a, 10b, and is connected to the life detecting circuit 12 through the electrode terminals 10a, 10b. The life detecting circuit 12 electrically disconnects the life detecting unit 11 due to wear (that is, disconnection of the electric circuit). And the life of the head portion (wear limit) is detected.

Here, the life detecting circuit 12 has only to have a configuration capable of detecting disconnection of the electric circuit, and may be a circuit which can be manufactured easily and at low cost. FIG. 4 shows a configuration example of the life detecting circuit. FIG. 4A shows a switch 14, a power supply 15, an ammeter 16 (or a voltmeter 1) on the gap spacer 7.
7), an example in which a life detecting circuit 12 including a current adjusting resistor R is connected, and a switch 14 is turned on in conjunction with a main switch of the magnetic recording / reproducing apparatus;
While the switch 14 is ON and the life detecting portion (slit portion) 11 of the gap spacer 7 is not worn, the ammeter 16 (or voltmeter 17) indicates a predetermined current value (or voltage value). When the life detecting portion (slit portion) 11 of the gap spacer 7 is cut due to wear of the head portion, the electric circuit is cut off, and the value of the ammeter 16 (or the voltmeter 17) becomes zero. Life detection unit 1
Even before 1 is cut, the resistance increases when the cross-sectional area is considerably reduced due to wear, so that the resistance greatly increases compared to the initial current value (or voltage value), and it is easy to shorten the life of the magnetic head. Can be predicted. Therefore, if the ammeter 16 (or voltmeter 17) shown in FIG. 4A is installed at a position that is easy to see at the time of periodic inspection, the life (wear limit) of the magnetic head can be easily detected.

FIG. 4B shows a simpler configuration of the life detecting circuit 12, in which a pilot lamp 1 composed of a light emitting diode or the like is provided at one terminal of the gap spacer 7.
8, a switch 14, a power supply 15, and a current adjusting resistor R. The other end of the gap spacer 7 is grounded via a shield case or the like. The switch 14 is a switch that is turned on in conjunction with the main switch of the magnetic recording / reproducing apparatus. When the switch 14 is turned on and the life detecting unit (slit) 11 of the gap spacer 7 is not worn, the switch 14 Electric current flows through the pilot lamp 18
Is lit. However, when the life detecting portion (slit portion) 11 of the gap spacer 7 is cut due to wear of the head portion, the electric path is cut, so that the pilot lamp 18 is cut.
Turns off. Therefore, if the pilot lamp 18 is installed in a place that is easy to see from the outside of the apparatus, such as near the main switch, the magnetic head can be easily viewed only by checking the state (on / off) of the pilot lamp 18 without performing any special inspection. Life (wear limit) can be detected.

As described above, in the magnetic head of the present embodiment, the gap spacer 7 is cut by the wear of the head at the position h (<d) shallower than the effective depth d from the sliding surface of the magnetic medium 2 with the magnetic gap. And a life detecting circuit 12 is connected to the gap spacer 7, and the life detecting circuit 1 is provided by the life detecting circuit 12.
1, the life of the head portion (wear limit) is detected by detecting cutting due to wear, so that it is possible to easily detect that the head portion is about to reach its life (wear limit),
It is possible to know the appropriate replacement time of the magnetic head, and maintenance and management of the magnetic recording / reproducing apparatus are facilitated.

In the embodiment shown in FIG. 1, an example in which the life detecting section 11 is provided at one position of the gap spacer 7 is shown. In some cases, the head portion may be partially reduced, and before the life detecting portion 11 of the gap spacer 7 is cut, the reduced portion of the head portion may reach the wear limit. Therefore, in order to solve this problem, as shown in the example shown in FIG.
a, 11b, and 11c may be provided. In this way, even if the head part is depleted, before the head part reaches the wear limit, the life detecting part close to the depleted portion is cut off, so that the life of the head part (wear limit) is ensured. ) Can be detected.

In the case of a multi-channel type in which the magnetic recording / reproducing apparatus performs recording / reproduction on a plurality of tracks of the magnetic medium at the same time, the magnetic recording / reproducing apparatus corresponds to the plurality of tracks of the magnetic medium in the direction of the magnetic gap of the magnetic head. A plurality of magnetic cores 3a, 3b, 3c are arranged in parallel via a spacer 13. In such a case, as shown in FIG. 3, each magnetic core 3a, 3b, 3c (an example of three tracks) is provided. Correspondingly, the life detectors 11a to 1d
Is provided. In this way, even when the head portion having a plurality of cores is reduced, the life (wear limit) of the head portion can be reliably detected.

(Structural Example 2) Next, a third embodiment of the present invention will be described. 5A and 5B are diagrams showing a configuration example of a magnetic head to which the present invention is applied, wherein FIG. 5A is a perspective view of the magnetic head, and FIG.
FIG. 3 is a plan view of the magnetic head of FIG. This magnetic head 20 has a substantially U-shaped cross section and a recording (write) magnetic core 21 provided with a first winding 22, and a substantially U-shaped cross section and a smaller core width than the recording core 21. A second winding 28 is applied and positioned within the width of the above-described recording core width and abuts each other with a magnetic gap (gap spacer 29) therebetween so as to form a loop-shaped magnetic path with the recording core 21. The reproducing (lead) core 23 is closely arranged side by side with the laminated spacers 26 and 27 on both sides of the reproducing core, and is brought into contact with both ends of the recording core 21 with a magnetic gap (gap spacer 29) therebetween. Side cores 24, 2
5, the recording core 21 is a single core 20a, and the reproducing core 23 is a laminated core 20b. That is, the magnetic head 20 is provided with a magnetic gap (gap spacer 29).
The core portion 20b on one side sandwiching is a core portion having a laminated structure, and has a narrow reproducing core 23 and laminated spacers 2 on both sides thereof.
The other core portion 20a is a wide recording core 21 having a width equal to the reproducing core width and the side core width, and is composed of side cores 24 and 25 stacked via the cores 6 and 27.
This is a so-called wide write / narrow read (W / N) magnetic head having a configuration in which the recording width is wider than the reproduction width. Each magnetic core may be made of a magnetic material such as permalloy, sendust, or ferrite and formed into a predetermined shape, or a core having a predetermined core width formed by laminating a number of thin metal magnetic materials. Is used. The magnetic head shown in FIG. 5 is entirely covered with a shield case except for a head portion that is in sliding contact with the magnetic medium, but illustration of the shield case is omitted.

FIG. 6 is an explanatory view of the configuration of the magnetic head according to the embodiment of the present invention, and shows the configuration of the magnetic head shown in FIG. 5 more clearly. As shown in FIG. 6A, the core portion of the laminated structure has a structure in which side cores 24, 25 are laminated via laminated spacers 26, 27 on both sides of a reproducing core 23 on which a reproducing coil 28 is wound. The magnetic head shown in FIG. 5 is obtained by fixing the core portion 20b of this laminated structure to the recording core 22 with the gap spacer 29 interposed therebetween as shown in FIG. 6B.

According to the present invention, at least one of the laminated spacers (for example, 26) of the laminated spacers 26, 27 laminated between the reproducing core 23 and the side cores 24, 25 and having an interval between the cores, As shown in FIG. 6C, a conductive material (a non-magnetic conductive material such as phosphor bronze) 26b provided with an insulating layer (shaded portion in the figure) 26d on both surfaces, and a life detecting function is provided on the laminated spacer 26. This is a configuration in which the unit 30 is provided. Note that the life detecting unit 30 has a slit 26 at a substantially central portion of the conductive material 26b of the laminated spacer 26.
a is formed so that the width h of the sliding contact portion with the magnetic medium is smaller than the effective depth d of the magnetic gap portion 29 of the magnetic head, and the effective width of the magnetic gap portion 29 from the sliding surface of the magnetic medium is reduced. The electric circuit is cut off at a position shallower than the depth d due to wear of the head portion. That is, in this embodiment, the exposed portion of the conductive material provided at the lower end of the laminated spacer 26 is replaced with the electrode 26b,
A life detecting circuit 1 similar to that of the first embodiment is provided on the electrode as 26c.
2 and the life detecting circuit 12
By detecting the cutting (cutting of the electric circuit) due to wear of the head, it is possible to detect the life (wear limit) of the head portion.

The conductive material 26b of the laminated spacer 26
When the slit 26a is inserted into the
Electrode part 2 on both sides including slit part of conductive material 26b
By coating the insulating layer 26d on the entire surface except for 6b and 26c or attaching an insulating member, the slit portion is filled with the insulating material, and the strength can be increased.
Further, by providing the insulating layers 26d on both surfaces of the laminated spacer 26, even when the magnetic core is made of a metallic magnetic material, a short circuit with the core is prevented.

In the example shown in FIG. 6A, the laminated spacers 26 and 27 are formed in substantially the same shape as the side cores 24 and 25, and the laminated spacers 26 and 27 on both sides sandwiching the reproducing core 23. Since both have a life detector,
Even in the case where the magnetic head collides with the magnetic medium to reduce the wear, the wear of the head can be detected by one of the life detecting units. In addition, the life detecting unit 30 can be provided at a plurality of locations in a direction perpendicular to the magnetic gap (moving direction of the magnetic medium) by forming a plurality of slits in the laminated spacer or the like. However, by providing a plurality of life detecting sections, it is possible to cope with a case where the magnetic head and the magnetic medium have one side contact in the running direction.

FIG. 7A shows another example of the structure of the laminated spacer according to the present invention. The laminated spacers 26 and 27 are formed in accordance with the shape of the reproducing core 23, and are laminated on both sides of the reproducing core 23. Then, a winding 28 is provided integrally with the reproducing core 23. Also in this case, as in the example of FIG. 6, the laminated spacer 26 is formed of a conductive material 26b provided with an insulating layer (shaded portion in the figure) 26d on both surfaces as shown in FIG. 26, a configuration in which a life detecting unit 30 is provided. The life detecting unit 30 has a slit 26a formed at a substantially central portion of the conductive material 26b of the laminated spacer 26, and the width h of the sliding contact portion with the magnetic medium is smaller than the effective depth d of the magnetic gap portion 29 of the magnetic head. The electrical path indicated by the broken line in the figure is cut by wear of the head at a position shallower than the effective depth d from the magnetic medium sliding surface of the magnetic gap portion 29. That is, in the present embodiment, the same life detecting circuit 12 as that of the first embodiment is connected to the electrode terminal portions 26b and 26c formed by exposing a part of the conductive material of the laminated spacer 26 to the lower side. By detecting the disconnection (disconnection of the electric circuit) due to wear of the life detecting unit 30 by the use of 12, it is possible to detect the life (wear limit) of the head unit.

FIG. 8 is a view showing still another example of the structure of the laminated spacer according to the present invention. In the examples shown in FIGS. 6 and 7, the electric circuit is constituted only by the conductive material 26b of the laminated spacer, but in the example shown in FIG. 8, a metal magnetic material is used for the magnetic core and the life detecting section 30 is sandwiched. One of the electric circuits is made of the conductive material 26b of the laminated spacer, and the head body is used for the other electric circuit.

That is, in the example of FIG. 8A, the shape of the laminated spacer 26 is matched to the shape of the reproducing core, and a slit is provided in the laminated spacer 26 to form the life detecting section 30.
The insulating layer (hatched portion in the figure) 26d is coated except for the portion on the magnetic gap side from the life detecting section 30. When the insulating layer 26d is closely stacked on the reproducing core, the insulating layer 26d is closer to the magnetic gap side than the life detecting section 30. Since the exposed portion of the conductive material 26b contacts the reproducing core, an electric path from the laminated spacer 26 to the magnetic core via the life detecting unit 30 is formed. For this reason, if the magnetic core side is grounded, only one electrode terminal is provided on the laminated spacer side, and if a life detecting circuit is connected between the electrode terminal and ground, the example shown in FIGS. In the same manner as described above, the life of the head can be detected.

FIGS. 8 (b) and 8 (c) show, as the life detecting portion 30 of the laminated spacer 26, a portion in contact with the recording core 21 is formed with a width h smaller than the effective depth d of the magnetic gap. The leading end of the narrow portion is brought into contact with the recording core 21 and the recording core 21 is used as a part of an electrical path for life detection. Only one electrode terminal needs to be provided, and if the life detecting circuit 12 is connected between the electrode terminal and the ground, FIG.
7 and the life of the head portion can be detected in the same manner as in the example of FIG.

FIG. 8B shows an example in which the laminated spacer 26 is formed in accordance with the shape of the reproducing core 23 and the winding 28 is provided together with the reproducing core. FIG. In any case, both surfaces of the laminated spacer 26 are coated with the insulating layer 26d to prevent an electrical short circuit with the reproducing core or the side core. Further, a gap is provided between the laminated spacer 26 and the recording core 21 in order to prevent the recording core 21 from contacting other than the end of the life detecting unit 30 of the laminated spacer 26.

(Configuration Example 3) Next, another configuration example of the magnetic head will be described as a reference example . FIG. 9 is a diagram showing a configuration example of a magnetic head .
(A) is a perspective view of a magnetic head, (b) is a plan view when the magnetic head of (a) is viewed from above, and (c) is a B- line of (b).
It is principal part sectional drawing which shows the B line cross section. The cross-sectional structure of the magnetic head 40 shown in FIG. 9 is substantially the same as that shown in FIG. 10A, and a pair of magnetic members 41 and 42 are arranged by abutting a magnetic gap (gap spacer) 43 therebetween. Core, both sides of the magnetic cores 41 and 42 and the shield case 4
6, a side spacer 44 is provided between the magnetic core and the case so as to be spaced apart. Also,
A resin frame 45 is provided between the magnetic core and the case 46 to provide an interval between the magnetic core and the case and to fix the core and the case.

In this configuration example , the side spacers 44 are formed of a conductive material (a nonmagnetic conductive material such as phosphor bronze) provided with an insulating layer on both surfaces, and the side spacers 44 are provided with a magnetic gap 43. And a slit-shaped life detecting section 50 cut at a position h shallower than the effective depth d from the sliding surface of the magnetic medium due to wear of the magnetic head. As in the case of the laminated spacer of Example 2, a life detecting circuit (not shown) is connected to the electrode terminal of the side spacer 44, and the life detecting circuit detects a cut due to wear of the life detecting unit 50, whereby the head unit is detected. Life (wear limit) can be detected. Note that the configuration and the detection method of the life detection circuit are the same as those in the above-described embodiment, and thus the description is omitted.

FIG. 9D shows another example of the configuration of the side spacer 44.
This is an example in which a, 50b, and 50c are provided at a plurality of locations. By arranging the side spacers 44 having the life detecting portions 50a, 50b, 50c at a plurality of positions on both sides of the magnetic cores 41, 42, the life of the head portion can be detected more reliably.

[0037]

As described above, in the magnetic head of the present invention, the constituent members of the head portion, that is, the gap spacer which is sandwiched between a pair of magnetic cores to form a magnetic gap, or the magnetic core having a laminated structure. Either a laminated spacer laminated between the magnetic cores and having a space between the cores, or a side spacer disposed between the magnetic core and the shield case and spaced between the magnetic core and the shield case Is formed of a conductive material having an insulating layer on both surfaces, and the constituent member has a life detecting portion that is cut by abrasion of the head portion at a position shallower than the effective depth of the magnetic gap from the sliding surface of the magnetic medium. Provided, and electrically detects the cut due to wear of the life detecting unit, that is,
A life detecting circuit is connected to the conductive material of the constituent member, and the life detecting circuit detects a cut due to abrasion of the life detecting portion (cutting of an electric circuit) to detect a life of the head portion (wear limit).
Configuration without the need to perform special inspections such as periodic observation of the head and measurement of the wear width.
Before the head reaches the wear limit (life), it is possible to electrically detect that the life is near, so the magnetic head can be replaced before it reaches the end of its life. Etc. can be prevented beforehand. In addition, by providing the life detecting unit at a plurality of locations of the constituent members of the head unit, even when the magnetic head hits against the magnetic medium and the head surface is degraded, the life of the head unit is surely reduced. Limit) can be detected.

Therefore, according to the present invention, the life of the magnetic head can be detected accurately and before the end of the life, so that the magnetic head can be replaced at an appropriate time, and the life of the magnetic head being used is increased. Troubles (inability to use the device, destruction of magnetic data, etc.) can be avoided beforehand, and maintenance of magnetic recording / reproducing devices such as a magnetic card reader,
Management becomes easy and reliability can be improved. Moreover, life detection unit of the magnetic head in the present invention, since it is provided in a member constituting the gap spacer and stacking space Sa of what was originally a magnetic head, without changing the shape or configuration of the magnetic head can be easily realized, cost Up can also be kept to a minimum. In addition, the life detecting section can be formed by a simple process such as forming the above-described constituent members by coating a conductive material with an insulating layer or attaching an insulating member and providing slits and the like. Since it is provided on a constituent member, it is easy to manage dimensions in assembly and the like, and it is possible to accurately detect the wear limit of the magnetic gap.

[Brief description of the drawings]

FIGS. 1A and 1B are diagrams illustrating the configuration of a magnetic head according to an embodiment of the present invention, in which FIG. 1A is a diagram illustrating a cross section in a direction orthogonal to a magnetic gap of the magnetic head, and FIG. FIG. 3 is a diagram showing a cross section taken along line AA of FIG.
(C) and (d) are a plan view and a sectional view of a gap spacer which is one of the features of the present invention.

FIG. 2 is a view illustrating an embodiment of the present invention, and is a view illustrating an example of a gap spacer in which a life detecting unit is provided at a plurality of locations in a magnetic gap direction of a magnetic head.

FIG. 3 is a view showing an embodiment of the present invention, and is a view showing another example of a gap spacer provided with a life detecting section at a plurality of positions in a magnetic gap direction of a magnetic head.

FIG. 4 is a diagram illustrating an embodiment of the present invention, and is a diagram illustrating a configuration example of a life detecting circuit.

5A and 5B are diagrams showing a configuration example of a magnetic head to which the present invention is applied, wherein FIG. 5A is a perspective view of the magnetic head, and FIG. 5B is a plan view of the magnetic head of FIG. FIG.

6 (a) and 6 (b) are perspective views for explaining a component configuration and an assembling process of the magnetic head shown in FIG. 5, and FIG. )
FIG. 3 is a configuration explanatory view of a laminated spacer provided with a life detecting unit.

7A and 7B are diagrams showing an embodiment of the present invention, wherein FIG. 7A is a perspective view showing an example in which a laminated spacer provided with a life detecting unit is provided integrally with a reproducing core, and FIG. FIG. 4 is a configuration explanatory view of the laminated spacer shown in FIG.

FIG. 8 is a view showing an embodiment of the present invention, and is an explanatory view of still another configuration example of a laminated spacer provided with a life detecting portion and an electric path thereof.

FIG. 9 is a view showing a reference example , and is a configuration explanatory view of a magnetic head having a side spacer provided with a life detecting portion and a side spacer.

FIG. 10 is a configuration explanatory view of a magnetic head showing an example of a conventional technique.

[Explanation of symbols]

 1, 20, 40: magnetic head 2: magnetic medium 3, 4: magnetic core 5, 6: coil (winding) 7: gap spacer 7a: conductive material 7b: insulating layer 11, 11a, 11b, 11c, 11d: Life detecting unit 12: Life detecting circuit 20b: Laminated core 21: Recording core 22: Recording coil 23: Reproducing core 24, 25: Side core 26, 27: Laminated spacer 26b: Conductive material 26d: Insulating layer 28 : Reproduction coil 29: Magnetic gap (gap spacer) 30: Life detector 41, 42: Magnetic core 43: Magnetic gap (gap spacer) 44: Side spacer 46: Shield case 50, 50 a, 50 b, 50 c: Life detector d: Effective depth

──────────────────────────────────────────────────続 き Continuation of the front page (56) References Japanese Utility Model Sho 62-110706 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G11B 5/455 G11B 5/127 G11B 5 / 255

Claims (5)

(57) [Claims] 1. A magnetic head for recording and / or reproducing a signal by slidingly contacting a magnetic medium with a head portion comprising at least a pair of magnetic cores disposed to face each other with a magnetic gap therebetween, wherein: A gap spacer which is sandwiched to form the magnetic gap is formed of a conductive material having an insulating layer provided on both sides, and the gap spacer is positioned at a position shallower than the effective depth of the magnetic gap from the sliding surface of the magnetic medium. A life detecting unit which is cut by wear of the part, and a life detecting circuit is connected to the gap spacer, and the life detecting circuit detects a cut due to wear of the life detecting unit to detect a life of the head part (wear limit). A) a magnetic head characterized by detecting 2. A magnetic head according to claim 1, wherein said life detecting portion is provided at a plurality of positions of a gap spacer. 3. A magnetic head for recording and / or reproducing signals by slidably contacting a magnetic medium with a head portion comprising at least a pair of magnetic cores disposed opposite to each other with a magnetic gap interposed therebetween, wherein at least one magnetic core has a plurality of magnetic cores. A magnetic core having a laminated structure in which the magnetic cores are laminated, wherein a laminated spacer laminated between the magnetic cores and provided with an interval between the cores is formed of a conductive material having an insulating layer on both surfaces, To
A life detecting unit is provided at a position shallower than an effective depth of the magnetic gap from the rubbing surface of the magnetic medium, the life detecting unit being cut by abrasion of the head unit. A magnetic head for detecting a cut due to wear of a detecting portion to detect a life (wear limit) of a head portion. 4. The magnetic head according to claim 3, wherein the magnetic core having one layered structure comprises a narrow reproducing core and side cores laminated on both sides of the magnetic core via a laminated spacer, and the other magnetic core has A conductive material having a wide recording core having a width equal to a width of a reproducing core and a width of a side core, and an insulating layer provided on both surfaces of the laminated spacer laminated between the reproducing core and the side core and having an interval between the cores. A magnetic head characterized in that the life detecting unit is provided on the laminated spacer. 5. The magnetic head according to claim 3, wherein the life detecting section is provided at a plurality of locations of the laminated spacer or at a plurality of laminated spacers.