JPS6019045B2 - Multi-element magnetic head - Google Patents

Description

[Detailed Description of the Invention] As magnetic disk devices, magnetic drum storage devices, etc. used in external storage devices of electronic computers move toward larger capacities, higher speeds, and lower prices, the magnetic heads used in these devices also become more expensive. The trend is toward higher density and lower prices.

Therefore, Takechika announced a multi-element magnetic head that applied thin film integration techniques such as plating, vapor deposition, and etching, and several shapes have been proposed and are now 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. Stable and low price with little characteristic deviation between
High-density magnetic head elements can be provided. The method of transmitting and receiving signals between these magnetic head elements and external recording/reproducing circuits is to solder the lead wires one by one at the connection section on the floating slider of the multi-element magnetic head, or to There is a way to extract it by sonic pounding. However, since it is usually necessary to take out 2 to 3 lead wires per element, when the number of elements increases to 9 to 40, the number of lead wires becomes extremely large, approximately 20 to 120.
It is extremely difficult to connect the lead wire to a predetermined circuit terminal without complicating the connection at the bush connection terminal portion, and there are many disconnections during handling. Therefore, a conductive foil such as copper is pasted on a flexible insulating film such as polyimide, polyamide, or Teflon, and a flexible conductor is patterned by etching to obtain the required number of lead wires. An infrared reflow connection method has been proposed in which the connection terminal portion and the circuit connection portion are heated while moving an infrared light source relative to each other for batch soldering. 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, etc., they are formed on one plane in the manufacturing process.

This plane is normally used as a slider end face that is approximately perpendicular to the slider floating surface, and therefore the flexible conductor is connected in a direction parallel to this end face. In order to connect this flexible conductor to the floating slider and the circuit terminal located in the horizontal direction, it is necessary to bend the flexible conductor approximately 90 degrees at an appropriate position between the connecting terminal part and the circuit terminal part. . In such cases, repeated stress is applied to the bending part during the floating slider's following 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, resulting in a state where it cannot float. I tighten it. SUMMARY OF THE INVENTION An object of the present invention is to provide a multi-element magnetic head having a structure in which no stress is applied to the connecting portion of a flexible conductor that connects a magnetic head element portion to an external circuit. A feature of the present invention is that a flexible conductor is provided on the back surface of the slider, one end of which is connected to the connection terminal of the magnetic head element formed on the end surface of the slider, and the other end of which is drawn out along the back surface of the slider. It is to be fixed with a fixed beam.

This will be explained in detail below using the figures. FIG. 1 and FIG. Z 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 the recording medium surface 3 performs relative movement in the direction of U in FIG. 1 to record and reproduce information. 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, and is provided with a floating gap determined by the equilibrium point between the load applied from the support spring and the floating force of the slider. Furthermore, the support spring ensures followability to the surface of the recording medium. FIG. 2 is an enlarged view of the magnetic head forming end surface 2. FIG. In an example in which the floating slider is made of ferrite material, the conductor 7 and the connection terminal 9 are formed on the ferrite material, and the magnetic body 8 is formed on this conductor. It is clear that in this case, T becomes the track width, and the thickness of the conductor 7 becomes the magnetic head cap length.
From this figure, it can be seen 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 movable conductor 4. For example, the flexible conductor has a thickness of 0.0
10 on the flexible insulating film on the 2-0.1 side with a thickness of 0.1.
02 to 0.1 skin conductive foil 1 1 is formed,
As shown in FIG. 1, since it has to be pulled out along the support spring 5 in the direction of the support plate 6, a bent part 12 must be provided, and in the direction in which the floating slider 1 rolls with respect to the relative movement U, there is no torsion. The rigidity increases, making it difficult to bend, or as mentioned above, fatigue may break at this part, or the moment acts, causing the floating slider's angle of attack regarding the movement of the magnetic disk to become negative, making it unable to float. This can lead to serious problems in terms of reliability. In addition, since the flexible conductor 4 is located away from the slider back surface 13, positioning in the x, y, and z directions is required during the bonding work of the conductive foil 11 and the connecting terminal 9 in FIG. 2, which takes a short time. It is difficult to join them, which increases the cost and is likely to cause defects. In consideration of the above points, a bonding structure according to the present invention that provides stable floating performance between a flexible conductor and an element connection terminal and is inexpensive and easy to manufacture is shown in FIGS. 3 and 4. The ends of the flexible conductor are bent in advance by a press or the like at an almost right angle as shown by 16 in FIG. 3, and bar-shaped solder 15 is inserted between the flexible conductor and the element connection terminal as shown in FIG. Alternatively, either or both of the conductive foil 11 and the connecting terminal 9 are plated with solder, and the solder is melted while irradiating with infrared rays to join the conductive foil 11 and the connecting terminal 9. After soldering, the flexible conductor is fixed to the back surface of the slider with a fixing beam 14 made of metal or plastic having sufficient rigidity, as shown in FIG. By using the method described above, repeated stress is not applied to the right-angled bent part of the flexible conductor, such as the bent part 12 in Figure 1, and the same stress is not applied to the solder joint, so there is no possibility of fatigue disconnection. Reliability will be much improved. Furthermore, since the mirror conductor 4 is sandwiched between the fixing beams 14, the slider 1 and the mirror conductor 4 have a stronger fixing structure than those fixed with resin adhesive, etc., and are resistant to adhesive peeling due to vibrations, changes over time, etc. Can increase reliability. In addition, by using the fixing agent 14, the flexible conductor 4 can be fixed to the slider 1 with a uniform force in the width direction, thereby reducing the stress applied to the boundary between the fixed part and the non-fixed part of the flexible conductor 4. The reliability against breakage can also be increased. Conventionally, the bending part 12 increases the torsional rigidity of the flexible conductor, which has a serious effect on the floating state of the slider, but in FIG. By leaving it somewhat slack, the rigidity of the flexible conductor 4 is reduced,
In addition, since the slider is bent at a right angle in advance, there is no moment acting on the slider to change its attitude angle, and it has almost no effect on the slider's floating state or tracking ability with respect to the recording medium surface, increasing reliability in recording and playback. Sexuality also improves. Also, conductive foil 1 for solder fusion bonding
As can be seen from FIG. 4, the positioning of the connecting terminal 1 and the connecting terminal 9 only needs to be done in one direction (the track direction (x direction)), which can shorten the joining time and reduce the cost. As described above, the bonding structure between the flexible conductor and the element connection terminal according to the present invention has stable floating performance and is an inexpensive structure. Enlarged views of solder joints according to another method of the present invention are shown in FIGS. 5 and 6.

As for the head structure, both the joining methods shown in Figures 5 and 6 are the 3rd method.
This is the same as in FIG. In Fig. 4, the rising dimension h of the right angle bending of the sacrificial conductor end should be at most 1 to 1 to In cases where it is somewhat difficult to form a right angle bend with such a short dimension of about two ribs, the structure shown in FIG. 5 is easy to form. If only the rising dimension h was increased, the structure would be the same as the conventional structure shown in FIG. 1, and repetitive stress would be applied to the bent portion 16 at a right angle or a constant curvature and the solder joint portion, which would easily cause fatigue disconnection. As shown in Fig. 5, the flexible conductor 4 is bent twice more at right angles, and
If it is fixed to a part of the back surface 13 of the slider, repeated stress can be avoided as in FIG. 4, resulting in a highly reliable structure. At this time, defects in handling can be further reduced by filling the flexible conductor with resin or inserting and gluing beams. Further, in FIG. 6, a notch 18 is provided in a part of the slider 1 and the slider 1 is bent as shown in the figure.
6' shows a method of fitting the formed portable conductor into the notch. In this case, as shown in the figure, the flexible conductor 4 is wrapped around a beam 17 that has sufficient rigidity and fixed in a sacrificial manner.
Incorporating 7 will make the work even easier. Resin adhesive or the like is used to incorporate the slider into the beam 17 so that the conductive foil 11 and the element connection terminal 9 do not come into contact with each other on the same surface. Thereafter, solder is applied to bridge the conductive foil 11 and the connection terminal 9 and perform the bonding. Even with the joining method shown in FIG. 6, no repeated stress is applied to the flexible conductor and the solder joint, resulting in a highly reliable structure that is less prone to fatigue disconnection. Although FIGS. 3 to 6 described above are examples of right-angle bending, there is no problem even if a certain curvature is provided for ease of bending work.

Further, the number of bent portions is not limited to the illustrated example, and can be selected as desired. As described above, according to the present invention, in a multi-element magnetic head having an extremely large number of connection parts, 20 to 120 connection terminals to an external circuit, a connection part of a flexible conductor serving as an external lead wire is The structure is stress-free, which prevents the connection parts from peeling off, the movable conductor from breaking, and the floating posture of the slider to be stabilized.

[Brief explanation of drawings]

FIG. 1 is a diagram of the structure of a magnetic head based on the conventional method of connecting thin film magnetic heads with conductors, FIG. 2 is an enlarged explanatory diagram of the connecting portion of FIG. 1, and FIG. 3 is a structure of a magnetic head based on the connection method of the present invention. 4 is an explanatory diagram of the connection method according to the present invention, and FIG.
This figure is an explanatory diagram of another connection method of the present invention, and FIG. 6 is an explanatory diagram of another connection method of the present invention. 1...Floating slider, 2...Magnetic head forming end surface, 3...Recording medium, 4...
・Movable conductor, 5...Support spring, 6...Head support plate, 7...Conductor, 8...Magnetic material, 9...Connection Terminal, 10... competitive insulating film, 11... conductive foil, 12...
Bent part, 13... Back side of slider, 14... Fixed beam, 15... Bar solder, 16... Vertical bent part, 17... Beam, 19... Notch part. Oh Fusai 3 Wind Leopard 2 Illustrations Sai 4 Os Madara Sai 6 Illustrations

Claims (1)

[Claims] 1. A multi-element magnetic head comprising a floating slider and a plurality of magnetic head elements formed on an end surface substantially orthogonal to the floating surface of the floating slider, wherein the magnetic head is connected to a connection terminal of the magnetic head element on the end surface, and 1. A multi-element magnetic head comprising a flexible conductor drawn out along the back surface of a floating slider, and a part of the flexible conductor being fixed by a fixing beam on the back surface of the floating slider.