JPS5931128B2 - floating magnetic head - Google Patents

Description

[Detailed Description of the Invention] As magnetic disk devices, magnetic drum devices, etc. used in external storage devices for computers move toward larger capacities, faster speeds, and lower prices, the magnetic heads used in these devices also become denser. , and are moving in the direction of lower prices.

Recently, multi-element magnetic heads that utilize thin film integration techniques such as plating, vapor deposition, and etching have been announced, and several shapes have been proposed and are now publicly known. These integrated magnetic heads can form a large number of magnetic head elements at once on the end face of the floating slider of the magnetic head, and do not require manual work such as winding. It is possible to supply a stable, low-cost, high-density magnetic head with little characteristic deviation. The method of transmitting and receiving signals between these magnetic head elements and external recording and reproducing circuits is to solder the lead wires one by one at the connection terminals on the floating slider of the multi-element magnetic head or to take them out by ultrasonic bonding. There is a way. However, since it is usually necessary to take out 2 to 3 lead wires per element, when the number of elements increases from 9 to 40, the number of lead wires becomes extremely large, approximately 20 to 120. It is extremely difficult to connect the lead wires to a predetermined circuit terminal without complicating the connection process, and there are many disconnections during handling. Therefore, a flexible conductor made of conductive foil such as copper is pasted on a flexible insulating film made of polyimide, polyamide, Teflon, etc. and patterned by etching to obtain the required number of lead wires. An infrared reflow connection method has been proposed in which an infrared light source is heated and soldered all at once while moving the infrared light source relative to the connection terminal portion and the circuit connection portion. This method allows a large number of connections to be made stably in a short period of time. Incidentally, since the connecting terminal portion and the multi-element magnetic head portion are generally formed by plating vapor deposition etching or the like, they are formed on the same plane due to the manufacturing process. This plane usually uses a slider end surface that is approximately perpendicular to the slider floating surface, and therefore the flexible conductor is connected in a direction parallel to this end surface. To connect this flexible conductor to a circuit terminal located parallel to the floating slider, it is necessary to bend the flexible conductor approximately 900 degrees at an appropriate position between the connecting terminal portion and the circuit terminal portion. In such cases, repeated stress is applied to the bending part of the floating slider during its follow-up motion, resulting in fatigue breakage, or a moment is generated at the connecting part of the floating slider, causing the slider attitude angle to deviate greatly, making it impossible to float. or Therefore, in order to obtain a magnetic head structure that has stable floating performance and is reliable, it is necessary to flex the slider in a direction that is approximately perpendicular to the end surface where the multi-element magnetic head portion is formed and parallel to the slider floating surface. It is necessary to create a connection structure in which the conductors are connected. The present invention provides an inexpensive, easy-to-manufacture three-dimensional connection structure between a flexible conductor and a connecting terminal that has stable floating performance for a multi-element magnetic head that applies such thin film integration technology.

This will be explained in detail below using the figures.

FIGS. 1 and 2 show typical examples of the structure of a conventional multi-element integrated floating magnetic head. The magnetic head is formed on the end surface 2 of the floating slider 1, and information is recorded and reproduced by relative movement of the recording medium surface 3 in the direction U in FIG. The floating slider is supported and fixed to the head support plate 6 by a support spring 5 consisting of a gimbal spring or a load spring.
A floating gap is provided which is determined by the load applied by the support spring and the equilibrium point of the floating blade of the slider, and the support spring also ensures followability to the surface of the recording medium. FIG. 2 is an enlarged view of the end face 2 forming the magnetic head. In an example in which the floating slider is made of ferrite material, the conductor 7 and the connecting terminal 9 are formed on the ferrite material, and the magnetic body 8 is formed on this conductor. At this time, T is the track width,
It is also clear that the thickness of the conductor 7 corresponds to the magnetic headgap length. It will be seen from this figure that a large number of magnetic heads suitable for high-density recording with minute track widths, track pitches, and gap lengths can be easily formed simultaneously by plating, vapor deposition, etching, etc. Now, let us consider connecting the connection terminal of such a floating slider and an external circuit terminal through the flexible conductor 4. The thickness of the flexible conductor is, for example, 0.02 to 0.17! T7! A conductive foil 11 with a thickness of 0.02 to 0.1 m 711 is formed on a flexible insulating film 10 of 1.0 m, and is applied along the support spring in the direction of the head support plate 6, as shown in FIG. Since it has to be pulled out, a bent part 12 must be provided, and the relative movement U
In the direction in which the floating slider rolls, the torsional rigidity increases, making it difficult to bend, or as mentioned above, this may cause fatigue breakage at this part, or the moment acts on the magnetic disk of the floating slider. If the angle of attack associated with movement becomes negative, the aircraft may become unable to float, which poses a major problem in terms of reliability. If a structure in which the flexible conductor is connected in a direction approximately perpendicular to the end surface where the multi-element magnetic head is formed and approximately parallel to the slider floating surface can be realized, the bent portion 12 can be eliminated. The above-mentioned disadvantages are avoided.

As a way to achieve this, one end face 2 of the floating slider
A conceivable method is to connect the end face 13 and the other end face 13 by a manufacturing process applying thin film integration technology as shown in FIG. 3, and connect a flexible conductor on the connecting terminal q. Considering the practical manufacturing process of such a structure, photoresist coating,
It is generally difficult to form conductors on two surfaces 2 and 13 at the same time due to technical limitations in pattern formation, vapor deposition, and metal etching. Therefore, after forming one of the surfaces first,
This surface must be completely masked to form the second surface, and if not impossible, incomplete masking can significantly reduce yield and increase machining time, resulting in lower cost and higher production costs. It is difficult and impractical to form an element magnetic head. FIG. 4 shows an easy-to-manufacture and low-cost connection structure according to the present invention.

A multi-element magnetic head is formed on the end face 2, the conductors 7 of which extend to the ridge 14 at the boundary between the end face 2 and the back surface 13 of the floating slider. Conductive foil group 1 of flexible conductor 4
1 is also formed to have the same pitch as the conductor group 7 and approximately the same width. This flexible conductor is made to protrude from the end face 2 by a width d, and the conductor 7 and the conductive foil 11 are positioned so that the pitch centers of each group overlap with each other. To connect these, a solder bar 15 is placed parallel to the ridge 14, and the solder melted while irradiating infrared rays tends to aggregate on the conductor part with good solder wettability. By appropriately selecting the diameter, the connection can be made at the shaded area 16 in FIG. 4 without bridging with adjacent conductor connections. Here, it is desirable that d be equal to or larger than the diameter of the bar-shaped solder. Another method is to form a solder film in advance on either the conductor 7 or the conductive foil 11, or in the vicinity of the solder joint between the two by a method such as vapor deposition or plating, without using bar-shaped solder, as shown in FIG. After aligning the pitches in the same manner as above, infrared rays or the like may be irradiated. Of course, other heating methods other than infrared irradiation may be used as long as the solder can be heated to a temperature sufficient to melt the solder. The structure of a magnetic head produced by these methods is shown in FIG.

As can be seen from this figure, unlike the first example, the flexible conductor 4 does not have an extreme bend 12 and is fixed at a suitable position on the head support plate at a gentle angle, so the torsional rigidity due to the conductor portion is As a result, reliable and stable operation can be achieved. In addition, it is optional to narrow the conductive foil pitch or widen the overall width of the flexible conductor near the part on the back surface of the slider where the support spring 5 acts, as necessary, to create a structure in which the interfering part can escape. It is. Also, it is more desirable for the flexible conductor 4 to have some slack than to attach it to the head support plate under tension. With the structure described above, an extremely large number of connections such as 9 to 40 magnetic head elements and 20 to 120 connection terminals can be realized easily, in a short period of time, and at low cost, resulting in reliable and stable operation. is given. The method described here can be applied not only to recording/reproducing heads that apply thin film integration technology, but also to multi-track head mounting structures such as Hall element heads and magnetoresistive element heads. The present invention can be applied to multi-element magnetic heads in which not only the flexible conductor but also the magnetic head element portion is made of metal foil, and other structures that generally require three-dimensional wiring connections between different surfaces.

[Brief explanation of drawings]

Figure 1 is a diagram of the structure of a magnetic head using the previously proposed conductor connection method for thin-film magnetic heads, Figure 2 is an enlarged explanatory diagram of the connecting part in Figure 1, and Figure 3 is a diagram of a thin-film magnetic head with thin-film conductors on two adjacent surfaces. 4 is an explanatory diagram of the connection structure of the formed magnetic head, FIG. 5 is a diagram of the structure of the magnetic head according to FIG. 4, and FIG. 6 is a perspective view of the magnetic head conductor connection portion according to FIG. 4. It is a diagram. DESCRIPTION OF SYMBOLS 1...Floating slider, 2...Magnetic head forming end face, 3...Magnetic disk, 4...
...Flexible conductor, 5...Support spring, 6...
...Head support plate, 7...Conductor, 8...
...Magnetic material, 9,9... Connection terminal, 10...
... Flexible insulating film, 11 ... Conductive foil,
12...Bending portion, 13...Slider back, 14...Slider crest, 15...
...rod-shaped solder, 16...conductor connection part.

Claims (1)

[Claims] 1. A floating type having a connection band in which conductor rows are formed on a flexible nonconductor band, and connection pads for magnetic head windings arranged along a ridge line on a wall surface substantially perpendicular to the medium facing surface of a floating slider. The magnetic head has a connecting band extending from the adjacent ridgeline of the connecting pad along the back surface of the slider that is substantially perpendicular to the wall surface of the magnetic head, and that the connecting band merges with the conductor row at substantially right angles to the connecting band. A floating magnetic head characterized in that electrical connections are made by bridging connection pads on a wall surface with solder.