JP2946603B2 - Magnetic head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a floppy disk drive (FD)
D) The present invention relates to a magnetic head used in a magnetic disk device such as a device, and sometimes to holding a back bar for closing a magnetic circuit.

[Prior Art] FIGS. 5 and 6 show a conventional magnetic head, in which (1) is an L-shaped read / write core having a sliding surface, and (2) is a read / write core having a sliding surface. An auxiliary core having a sliding surface coinciding with the sliding surface of the read / write core, and forming a center core for forming a read / write gap of a predetermined length at the center of the joint between the sliding surfaces; The read / write core (1) and the auxiliary core (2) are adhesively fixed to the end opposite to the sliding surface with an adhesive to form a magnetic circuit closed by the cores (1) and (2). The first back bar,
(4) is a read / write coil wound around the read / write core (1), and has a signal input / output end.
(5) is an erase core having an L shape and having a sliding surface,
A sliding surface coinciding with the sliding surface of the auxiliary core (2);
An erase gap for forming a guard band at both ends of data recorded on the recording medium based on the read / write gap is formed at a joint between the sliding surfaces.
The magnetic circuit (6) is bonded and fixed to the end of the erase core (5) and the auxiliary core (2) on the side opposite to the sliding surface with an adhesive and closed by the cores (5) and (2). Is formed integrally with an end portion of the first back bar (3) with an adhesive made of a non-magnetic material. (7) is an erase coil wound around the erase core (5), which has an input / output end through which a constant current flows when recording a signal. (8) and (9) have sliding surfaces that match the sliding surfaces of the read / write core (1), the auxiliary core (2) and the erase core (5), and the read / write core (1) and the auxiliary core ( 2) A holder made of a non-magnetic material such as ceramic which holds the sliding surface side of the erase core (5) from both sides to stabilize contact with a recording medium.

In the magnetic head thus configured, the connection of the first and second back bars (3) and (6) to the read / write core (1), the auxiliary core (2), and the erase core (5) is as follows. After assembling as shown in FIG.
The back bars (3) and (6) are assembled by bonding with an adhesive to the end opposite to the sliding surface of the read / write core (1), the auxiliary core (2) and the erase core (5). is there.

Next, a case where data is recorded and a case where data is reproduced from a magnetic medium such as a floppy disk using the magnetic head thus configured will be described. First, a case where data is recorded on a recording medium will be described. A signal corresponding to the data to be recorded is applied to the input / output terminal of the read / write coil (4), and a constant voltage is applied to the input / output terminal of the erase coil (7). Then, a magnetic flux appears in the read / write gap based on a signal or a current flowing through the read / write coil (1), and data corresponding to the signal is written on a recording medium. In addition, since a constant current is passed through the erase coil (7),
A constant magnetic flux appears in the erase gap, and a gart band is formed at both ends of the data recorded by the read / write gap (3).

On the other hand, when reproducing (reading) the data recorded on the recording medium, when the magnetic head is slid over the recording surface of the recording medium without passing a current through the erase coil (7), the recorded data is read. Changes in the magnetic flux appear in the read / write gap, thereby causing a current to flow through the read / write coil (4). As a result, a reproduced output voltage corresponding to the data recorded at the input / output terminal of the read / write coil (4) appears and is reproduced.

[Problem to be Solved by the Invention] In the magnetic head configured as described above, the first
Also, since the second back bar (3) (6) is connected to the read / write core (1), the auxiliary core (2) and the erase core (5) with an adhesive, the first back bar may vary due to a variation in the bonding operation. And the adhesiveness of the second back bars (3) and (6) decreases, and the adhesive swells or contracts due to the influence of the ambient temperature and humidity, and the adhesiveness changes, so that recording,
There is a problem that the reproduction performance is not stable.

The present invention has been made in view of the above points, and has as its object to obtain a magnetic head in which there is no variation in the mounting operation of the back bar, and the degree of adhesion of the back bar does not easily change depending on the ambient temperature and humidity. It is assumed that.

[Means for Solving the Problems] In a magnetic head according to the present invention, first and second back bars are respectively connected to ends of a read / write core and an auxiliary core, and ends of an erase core and an auxiliary core. And a ring-shaped frame provided around the first and second back bars and projecting inward from the frame and in contact with substantially the center of the first and second back bars. A first and a second protrusion, wherein the first and the second
And a back bar holding member formed of an elastic body such as a resin that generates a necessary holding force when the back bar comes into contact with the read / write core, the erase core, and the auxiliary core.

[Operation] In the present invention, the back bar holding member maintains the contact state between the back bar and both cores and suppresses variations in the degree of adhesion due to attachment of the back bar and changes in the degree of adhesion due to ambient temperature and humidity. .

[Embodiment of the Invention] Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 and 2. In the drawings, (10) indicates the first and second back bars (3) and (6). Peripherally provided first and second back bars (3) (6) and three cores (1) (2)
A back bar holding member for maintaining a contact state with (5), a ring-shaped frame (10a), and first and second back bars (3) (3) protruding inward from the frame (10a). The first and second protrusions (10b) and (10c) contacting at substantially the center of 6).
And the first and second back bars (3) and (6)
It is made of an elastic body such as resin which generates a necessary holding force when the cores (1), (2) and (5) are brought into contact with each other.

In the magnetic head thus configured, the connection of the first and second back bars (3) and (6) to the read / write core (1), the auxiliary core (2), and the erase core (5) is as follows. After assembling as shown in FIG.
The back bars (3) and (6) of the read / write core (1),
The first and second back bars (3) and (6) are inserted in a state in which the first and second back bars (3) and (6) are in contact with the ends of the auxiliary core (2) and the erase core (5) opposite to the sliding surfaces. Attach the holding member (10) and assemble. As a result, one inner surface of the back bar holding member (10) is a read / write core (1),
The first and second protrusions (10b) (10c) are in contact with the end faces of the auxiliary core (2) and the erase (5), and are substantially in the center of the first and second back bars (3) and (6). When the first and second back bars (3) and (6) come into contact with each other, a force is continuously applied in a direction in which the read / write core (1), the auxiliary core (2) and the erase core (5) come into close contact with each other.

Accordingly, the first and second back bars (3) and (6) can be easily attached to the read / write core (1), the auxiliary core (2) and the erase core (5) without variation, and at the time of recording and reproducing. The degree of adhesion does not change under the influence of the surrounding temperature and humidity, and the read / write core (1), the auxiliary core (2) and the erase core (5) of the first and second back bars (3) and (6) do not change. ) Can be prevented from deteriorating in recording and reproduction performance.

It should be noted that the magnetic head configured as described above operates in the same manner as that of the above-described conventional example, both when recording and reproducing data on the magnetic recording medium.

FIGS. 3 and 4 show another embodiment of the present invention, which differs from the embodiment shown in FIGS. 1 and 2 in that first and second back bars (3) ( 6) is made to contact the read / write core (1), the auxiliary core (2) and the erase core (5) on the opposite sides in a state of being separated. As a result, the back bar holding member (10) protrudes inward from the respective inner surfaces of the ring-shaped frame (10a), and the first and second back bars (3).
The first and second protrusions (10) contacting at substantially the center of (6)
b) (10c), and step portions (10d) (1) on the inner surfaces of the corners, which contact the read / write core (1) and the erase core (7), respectively.
0e).

The magnetic head thus configured can be assembled in the same manner as the magnetic head of the above-described embodiment, and has the same effect.

In the above embodiment, no adhesive is used when the first and second back bars (3) and (6) are brought into contact with the read / write core (1), the auxiliary core (2) and the erase core (5). Although the device has been described, the same effect can be obtained even if the device is fixed in advance with an adhesive for temporary fixing or the like.

[Effect of the Invention] As described above, according to the present invention, the first and second back bars are respectively connected to the ends of the read / write core and the auxiliary core, and the ends of the erase core and the auxiliary core. , The first and second back bars are provided around the first and second back bars, and project inwardly from the frame and contact at substantially the center of the first and second back bars. The first and second back bars are made of an elastic body such as a resin which generates a necessary holding force when the first and second back bars come into contact with the read / write core, erase core and auxiliary core. Since the back bar holding member is provided, variations in the degree of adhesion due to variations in the work of attaching the back bar and changes in the degree of adhesion due to ambient temperature and humidity are suppressed, and recording and reproduction performance is reduced. It has the effect of being fixed.

[Brief description of the drawings]

1 and 2 are a perspective view and an assembly view showing one embodiment of the present invention, and FIGS. 3 and 4 are a perspective view and an assembly view showing another embodiment of the present invention, and FIGS. FIG. 6 is a perspective view and an assembly view showing a conventional magnetic head. In the figure, (1) is a read / write core, (2) is an auxiliary core, (3) and (6) are first and second back bars, and (1)
0) is a back bar holding member. Note that the same reference numerals in the drawings indicate the same or corresponding parts.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G11B 5/265

Claims (3)

(57) [Claims] 1. A read / write core and an erase core having the same sliding surface, a sliding surface corresponding to the sliding surfaces of both cores, and a read / write gap at a joint with the read / write core. An auxiliary core that forms an erase gap at the junction with the erase core, and a magnetic circuit closed by the read / write core and the auxiliary core, which are connected to the ends opposite to the sliding surface of the auxiliary core. A second back bar connected to an end of the erase core and the auxiliary core opposite to a sliding surface of the erase core and the auxiliary core to form a magnetic circuit closed by these two cores; and Provided around the first and second back bars,
A ring-shaped frame, and first and second protrusions projecting inward from the frame and in contact with substantially the centers of the first and second back bars; A magnetic head comprising a back bar holding member made of an elastic body such as a resin which invents a necessary holding force when the back bar is brought into contact with the read / write core, erase core and auxiliary core. 2. The first back bar and the second back bar,
These ends are integrally formed by bonding with an adhesive made of a non-magnetic material, and the first and second protrusions of the back bar holding member are formed on the same side of the integrally formed back bar. 2. The magnetic head according to claim 1, wherein the magnetic head is in contact with the end of the read / write core, the erase core, and the auxiliary core on a side opposite to the contact portion. 3. The first back bar and the second back bar are formed separately, and each of the back bars contacts the first and second projections of the back bar holding member on opposite sides. 2. The magnetic head according to claim 1, wherein the read / write core and the auxiliary core are in contact with the erase core and the auxiliary core on opposite sides of the first and second protrusions, respectively. .