JPH0826772A - Glass for fusing, its production and apparatus for production and production of magnetic head - Google Patents

Abstract

PURPOSE:To facilitate manufacture of a magnetic head and to obtain the magnetic head with which joining strength is securely maintained and which has high reliability by necessitating one time of glass manufacture, grooving and glass setting operations. CONSTITUTION:A glass part 18A which consists of a compsn. improved in alkaline resistance and which alone has an optimum fusing temp of 580 deg.C and a glass part 18B which alone has an optimum fusing temp. of 560 deg.C are integrated to form the glass rod 19 for fusing. This glass rod 19 for fusing is set on a groove 21 atop a slider blank 20. A groove 22 to be inserted with a head chip 23 communicates with the groove 21 to enable pouring of the glass set in the groove 21 into the groove 22. The glass part 18B melts first to fill the narrow spacing between the slider blank 20 and the head chip 23 when the glass rod 19 for fusing is heated to 560 deg.C. The fused glass part 18A, then, fills the spacing in the upper part of the part 18B.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for manufacturing glass for fusing, and a method for manufacturing a magnetic head, for example, a method for manufacturing glass for fusing used for bonding magnetic head constituent materials and the method. And a method for manufacturing a magnetic head.

[0002]

2. Description of the Related Art Bonding glass is used for bonding magnetic head constituent materials such as fixing or embedding a core of a magnetic head, and fusion bonding is performed by heating in an electric furnace. By the way, in recent years, in the field of bonding glass for magnetic heads, along with higher performance of magnetic heads, in particular, lowering of fusion temperature and environmental reliability (water resistance, alkali resistance, etc.) have been required. There is.

For example, an amorphous alloy having a high magnetic flux density has come to be used for the core of a magnetic head, but the amorphous alloy generally has a low crystallization temperature (400 to 500).
Therefore, it is necessary to perform glass bonding at a temperature as low as possible below the crystallization temperature. Furthermore, since the glass is exposed to grinding water or a cleaning liquid during processing of the magnetic head, the glass exposed on the sliding surface of the magnetic head must be reliable at a practical level in terms of corrosion resistance to these liquids. .

Further, in general, a core block of a magnetic head for data storage is manufactured through a bonding step of two or more times in order from a high melting point glass to a low melting point glass in order to bond the constituent members thereof. Figure 12 shows a magnetic head core for a floppy disk. First, one recording / reproducing core 43A is formed by bonding the side core 43Aa and the center core 43Ab (both cores are generally made of ferrite) to each other by the glass 44A in the first bonding.

Similarly, the other erasing core 43B is also formed by bonding the side core 43Ba and the center core 43Bb with the glass 44A by the first bonding. next,
Both cores 43A and 43B are integrated by the second bonding with glass 44B. Subsequently, both the cores 43A and 43B are sandwiched between the sliders 42 and 45 on both sides, and the third bonding is performed by the glass 44C to form a core block.

FIG. 13 shows a magnetic head core for a hard disk. Cores 39A and 39B are joined by a first bonding with glass 41A, then assembled at a predetermined position of slider 38, and a second bonding with glass 41B is performed. Is done.

Therefore, in the above-described head manufacturing process by a plurality of bondings, the glass used for the second and subsequent bondings is required to have physical properties so as not to shift the bonding position of the previously bonded members. A glass with a low melting point is used so as not to soften the glass already used in the previous bonding.

Moreover, since the second bonding glass 44B of the floppy disk head core and the second bonding glass 41B of the hard disk magnetic head core are exposed on the head sliding surface, they react with the alkaline cleaning liquid or water in the air during processing. Then, if it is eluted and a step is generated, it will damage the magnetic recording medium. Therefore, it is required to have high reliability in terms of corrosion resistance against water and alkali.

Rod-shaped glass is mainly used for bonding magnetic head cores and the like. For example, in order to connect a pair of cores, as shown in FIG. 14, the core material blocks 50 and 51 are butted, and the groove 52 of the core material block 50 is
The rod-shaped glass 32A is inserted, heated and bonded by glass fusion to bond the core material blocks 50 and 51 as shown in FIG. Reference numeral 53 in the drawing is a groove for regulating the track width, and the molten glass is supplied through a large number of grooves 53. By thus using the glass in the shape of a rod, the amount of glass is controlled and the efficiency of glass setting work is improved.

There are two methods for producing the above rod-shaped glass, a pull-up drawing method and a pull-down drawing method. FIG. 16 is a schematic view showing the concept of manufacturing rod-shaped glass by the pull-up drawing method. That is, the glass raw material is melted in the crucible 30, and the melt 32 is heated by the heater 33 so as to maintain a constant viscosity, and in this state, the melt 32 is picked up with tweezers or the like and pulled up to be naturally cooled. A solid glass rod 32
Become A. This is sandwiched between a pair of rubber rolls 31, 31 rotated by a driving means (not shown) and continuously pulled up to manufacture a glass rod.

FIG. 17 is a schematic view showing the concept of the draw-down wire drawing method. That is, the glass raw material 32 melted in the crucible 34,
By appropriately controlling the temperature of the heater 36 above and below, the heater 36 is slowly and naturally dropped from the nozzle below the crucible 34. Then, the glass 32A, which is naturally cooled and solidified into a rod shape, is sandwiched between a pair of rubber rolls 35, 35 rotated by a driving means (not shown) and continuously pulled down to manufacture a glass rod.

In order for the magnetic head core to exhibit good electromagnetic conversion characteristics, a highly accurate magnetic gap having a width of submicron order or less is required on the coupling surface of both cores. Therefore,
The glass is not melted in such a part and its surroundings even at a low temperature and the magnetic characteristics of the core are not deteriorated, the gap shape is kept constant, and the reliability is such that a step is not generated in a normal environment. A glass having such a composition is preferable.

That is, as described in the section of the low melting point glass used for the head and the data storage using the amorphous alloy, the lower the fusion temperature is, the more preferable as the bonding glass, but the glass appearing on the sliding surface of the magnetic head is Practical reliability of moisture resistance, alkali resistance, etc. is required. However, there is a trade-off between low fusion temperature and high reliability, and glass with low fusion temperature is not suitable for the sliding surface of the magnetic head, and conventionally, the glass surface is not wetted as much as possible. In this way, even if the yield is lowered due to some magnetic characteristics or the shape of the gap, a glass having a slightly higher fusion temperature is used.

One of the ways to do this is to distinguish between the glass exposed on the sliding surface and the glass to be used in other areas, and to set the setting points for each glass and fuse the separately set glasses at the same time. However, not only is it a great deal of trouble and annoyance, but sometimes each glass is used incorrectly. In such a case, the quality of the product is deteriorated, and further, defective products are generated, resulting in deterioration of both reliability and productivity.

[0015]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and conventionally, a plurality of rod-shaped glasses having different compositions from each other were separately prepared, and these were used as core blocks. Instead of setting and fusing each at multiple points, the rod-shaped glass is manufactured once and the core block is set at one point, and the same functional fusion as the former is performed. An object of the present invention is to provide a fusing glass that can be used, a method and an apparatus for manufacturing the fusing glass, and a method of manufacturing a magnetic head using the fusing glass.

[0016]

That is, the present invention relates to a fused glass in which a plurality of glass portions having different compositions are integrated.

Further, in the present invention, it is advantageous for the manufacture of the magnetic head that the plurality of portions have different optimum fusion-bonding temperatures from each other.

Further, in the present invention, it is desirable that the plurality of portions have different compositions from each other so as to show different wettability with respect to the material to be fused at the fusion temperature, and further, the glass for fusion has a rod shape. It is desirable that

Further, in the present invention, each of the plurality of portions may have a rod shape, and the plurality of portions may be arranged side by side in the width direction and joined to each other.

The glass for fusing according to the present invention is particularly suitable for fusing magnetic head constituent materials.

The present invention also provides a plurality of containers each equipped with a stirring means and a gas supply means, a stopper mechanism, a control mechanism, and a heating means for heating the plurality of containers when manufacturing the above glass for fusion. , And liquid glass raw materials having different compositions melted in each of the above-mentioned containers, depending on the gas pressure and the self-weight of the liquid glass raw material, 5 to 150 cm /
The present invention relates to a method for manufacturing glass for fusing, which comprises extruding from the openings of the respective containers at a speed of sec to combine them with each other.

In the above, it is desirable to cool the extruded liquid glass raw material by a cooling mechanism.

The present invention also provides a plurality of containers each having a stirring means, a gas supply means, and an opening for pushing out the liquid glass raw material, a stopper mechanism for closing and releasing the opening, a heating means, and An apparatus for carrying out the above method, comprising a control mechanism.

In the above, it is desirable to further provide a cooling mechanism for cooling the extruded liquid glass raw material.

The present invention also relates to a method of manufacturing a magnetic head in which the above-mentioned glass for fusing is used to fuse the constituent material of the magnetic head.

In the above, the gap between the magnetic head chip and the slider material for protecting the magnetic head chip can be melted and filled as glass for fusing.

Further, in the above, the gap between the magnetic cores may be filled with glass for fusing.

[0028]

Embodiments of the present invention will be described below.

First, the glass for rod-shaped fusing, its manufacturing method and manufacturing apparatus will be described.

FIG. 1 shows a glass rod for fusing. FIG.
The glass rod 19 for fusing shown in (a) is formed by joining and joining two elongated glass parts 18A, 18B each having a generally semi-cylindrical shape at a flat surface. Glass rod 29 for fusing shown in FIG.
Is an elongated glass part 28 with a semicircular cross section.
A and 28B are joined and united at a flat portion, and have a circular cross-sectional shape as a whole. Glass part 18A, 28
A and 18B and 28B have different compositions and properties as shown in the following table.

[0031] Note) α is the coefficient of thermal expansion, and Tw is the optimum fusion temperature alone. The glass portions 18A and 28A are made to contain Bi ₂ O ₃ (bismuth oxide) to improve the alkali resistance.

Although the glass rod for fusing shown in FIG. 1 (a) has a non-circular cross section, it does not cause any problems in use and is easy to manufacture. However, as will be described later, the glass rod for fusing shown in FIG. 1 (b) can also be manufactured.

The glass rod for fusing shown in FIG. 1 (a) is manufactured as follows.

FIG. 2 is a schematic view showing a main part of an apparatus 1 for manufacturing a glass rod for fusing. Two crucibles 3A and 3B whose lower part is surrounded by a heater 12 are installed above the inside of a housing 2 of the device 1. A motor 7 as a drive unit for the stirring means 5A and 5B is installed on the upper part of the housing 2, and the bevel gear 7 is provided at the tip of the drive shaft.
A is located above crucible 3A and bevel gear 7B is located in crucible 3A.
It is located above B and is coaxially connected. The bevel gear 7A engages with the bevel gear 8A fixed to the upper end of the rotary shaft 5A of the stirrer of the crucible 3A, and the other bevel gear 7B engages with the bevel gear 8B fixed to the upper end of the rotary shaft 5B of the stirrer of the crucible 3B. are doing.

One stirring shaft 5A is inserted into the crucible 3A, and the other stirring shaft 5B is similarly inserted into the crucible 3B through the common upper lid 4 covering the crucibles 3A and 3B, respectively.
Arms 15A and 15B as a stirring means are provided at the tips of the respective members, and the arms are immersed in the glass melts 118A and 118B.

A pipe 13a extending from the gas supply pipe 13 is provided to the crucible 3A with a valve 14A provided on the way, and a pipe 13b branched from the gas supply pipe 13 is also provided to the other crucible 3B. A pipe is provided with a valve 14B, and these pipes penetrate the upper lid 4 of the crucible and extend to the inside of the crucible to which the respective tips belong. Gas supply pipe 13 is gas
17 is sent into each crucible, and the glass pressure of the glass raw material melts 118A and 118B is pushed out (blown) at a desired speed (5 to 150 cm / sec) together with its own weight as described later by the gas pressure.

The lower portions of the crucibles 3A and 3B are reduced in diameter to form nozzles (or orifices), and their outlets are diagonally opposed to each other. FIG. 4 is an enlarged view of the crucibles 3A and 3B. As shown in the figure, the crucibles 3A and 3B are formed by vertically extending a cylinder into two.
With a semi-circular cross-section as if divided, the lower part is reduced to form nozzles 3Aa and 3Ba that are inclined toward the center of the circle. Both crucibles are connected between the two crucibles with a spacer 16 sandwiched vertically. Then, the upper openings 3Ab and 3Bb
Is covered with an upper lid 4 to be hermetically sealed, and the lower nozzle 3Aa,
A stopper mechanism 6 is installed in the opening of 3Ba so as to be vertically movable and rotatable, so that the glass raw material melts 118A and 118B are intermittently pushed downward and dropped.

Further, in FIG. 2, a cooling mechanism 9 is installed below it, and a storage mechanism 10 for storing a glass rod 19 for fusion as a product is installed at the bottom.
A control mechanism 11 is installed outside, and is connected to the inside of the housing 2 by wiring to control the operation of each part.

Glass raw materials having different compositions are supplied to the respective crucibles 3A and 3B (the supply ports are not shown). For example, a glass material having a high melting point and a glass material having a low melting point are classified according to the use. Supplied. In this example, the glass melt 118A in the crucible 3A is fused with the glass rod 18A for fusing.
The glass melt 118B in the crucible 3B has the composition of the glass 18B for fusing. It should be noted that the crucibles may each be provided with a required mechanism to form a plurality of three or more crucibles.

In a state where the nozzles (or orifices) 3Aa and 3Ba are previously closed by using the stopper mechanism 6, the crucible 3 is
The glass raw materials (glass powder or cullet) supplied into A and 3B are heated by the heater 12 and melted to form a melt.
It becomes 118A, 118B. When melting these, the viscosities of the melts 118A and 118B should be adjusted so that the glass composition becomes uniform.
It is possible to blow glass through a clarification (foam removal) step (stop stirring to allow bubbles to escape) after the glass raw material has been completely melted while stirring for a certain time at a temperature of about 0.5 Pa · sec or less. Temperature This temperature can be determined depending on the glass composition, the blowing gas pressure, the nozzle diameter, and the like.

As shown in FIG. 3, the glass raw material melts 118A and 118B are blown out from the nozzles 3Aa and 3Ba of the crucibles 3A and 3B by lowering and rotating the stopper mechanism 6 in an instant, and from that point of time. After timing T ₁ , the electromagnetic valves 14A and 14B are opened to send the gas 17 into the crucible, and a preset gas pressure is applied to the crucibles 3A and 3B. At this time, the gas pressure of each crucible is adjusted according to the glass composition.

As a result, the melts 118A and 118B are continuously blown out obliquely from the nozzles 3Aa and 3Ba below the crucibles 3A and 3B and coalesce, and they are extremely rapidly cooled and rapidly solidified while dropping at a high speed. In the amorphous state, the rod-shaped glass 19 is solidified into a rod-shaped glass 19 shown in FIG. The timing T ₁ can be changed according to the surface tension of the melts 118A and 118B. By constructing the apparatus in this manner, the glass for fusion bonding (drawing) can be speeded up and is suitable for mass production.

FIG. 1 (a) shows a glass rod 19 for fusion, which is manufactured in the above-mentioned manner in a rod shape, and is obtained by injecting a high melting point glass melt 118A and a low melting point glass melt 1
What was injected from 18B is a rod-shaped unit. Therefore, those ejected from the circular or semi-circular nozzles are joined and united, and have the above-described shape. As shown in FIG. 4, a funnel-shaped tube F shown by an imaginary line is installed immediately below the nozzles 3Aa and 3Ba, and the glass melt 118A, 118B blown out from each nozzle is passed through the funnel-shaped tube F immediately before solidification. As a result, it is possible to obtain a glass rod 29 for fusing having a circular cross section as shown in FIG.

In order to realize such ultra-quick cooling of the glass, the apparatus is configured as described above, and the glass is discharged from the orifices or nozzles 3Aa, 3Ba at the bottom of the crucibles 3A, 3B.
Although 118A and 118B are blown out by the gas pressure and the own weight of the glass, the device is constructed so that the gas for blowing out the glass does not leak out of the crucible from the part other than the orifice or nozzle, and the gas pressure is controlled arbitrarily The cooling rate can be changed for each composition. If the cooling rate is insufficient only by controlling the gas pressure, the cooling mechanism 9 attached to the lower side of the orifices or the nozzles 3Aa, 3Ba is used to further quench the cooling gas by ejecting the cooling gas. It is possible to more reliably realize that the glass for fusing is manufactured in the shape of a rod by increasing the temperature.

The control of the blowing rate (extrusion rate) of glass is extremely important. That is, if the blowing speed of the glass is less than 5 cm / sec, the pressure for combining the two glasses is lost, and if it exceeds 150 cm / sec, the pressure of the blown molten glass colliding with the other glass is too strong and scatters. It becomes difficult to make it into a rod shape. Therefore,
It is essential that the blowing speed be 5 to 150 cm / sec.

The blowing speed is controlled by the pressure of the blowing gas 17 and the own weight of the glass melt. The gas pressure varies depending on the composition and weight of the glass, the blowing temperature, and the orifice diameter of the crucible. The blowing speed is 5
It should be 150 cm / sec, but a particularly preferred blowing rate is 10-50 cm / sec.

The above-described basic mechanism of the apparatus and the blowing speed of the glass make it possible to fabricate a plurality of glass rods as one glass rod while uniting them.

An inert gas such as Ar is used as the gas 17 for blowing glass, but compressed air can be used as long as it does not affect the glass composition. However, when using compressed air, it is desirable to use clean air from which oil and the like have been removed so that impurities are not mixed in the glass.

In the production of a glass rod by this apparatus, in the case of a thick glass rod having a wire diameter of 0.5 mmφ or more in the glass portion having only one composition, or when the glass transition temperature is 350
In the case of a low melting point glass having a temperature of ℃ or less, it is hard to be solidified, and therefore it is preferable to draw it through the cooling mechanism 9 in order to prevent it from falling into the storage mechanism 10 in a liquid state. Cooling mechanism 9
In order to prevent the falling liquid glass raw materials 118A and 118B from being abnormally deformed, the gas is uniformly sprayed from the surroundings to cool.

Next, the production of a magnetic head using the glass rod for fusion will be described.

FIG. 5 shows an example of use of the glass rod for fusing, and is an enlarged perspective view of a main part in a manufacturing process of a magnetic head for a hard disk, which will be described later. A groove 21 is provided on an upper surface of a slider material 20 which is a constituent member of a magnetic head, and the fusing glass 19 shown in FIG. 1A is set in the groove 21 and heated. A groove 22 is also provided on the side surface of the slider material 20, and a head chip 23 is previously incorporated and set in this groove 22. The head chip 23 is formed by bonding the gap portion with glass (41A in FIG. 13) having a glass transition point Tg of about 570 ° C.

Therefore, when the glass rod 18 for fusion is heated to 560 ° C. (see the above table) which is the optimum fusion temperature of the glass portion 18B of the glass rod 19 for fusion, and the glass rod 19 for fusion begins to be melted, first, the oblique line with the low fusion temperature is used. The molten glass portion 18B is melted from the marked glass portion 18B, and due to its good wettability, the molten glass portion 18B flows into the extremely small gap between the groove portion 22 of the slider 20 and the head chip 23 to fill the lower portion of the gap. Subsequently, the glass portion 18A that starts to melt after a later time fills the upper portion of the groove 22 on the sliding surface side of the portion filled with the glass portion 18B. Since the viscosity of the glass portion 18A at 560 ° C. is higher than that of the glass portion 18B, the capillary phenomenon is unlikely to occur, and the glass portion 18A always covers the upper portion of the glass portion 18B.

As a result, the glass portion 18A having a composition having a high fusion temperature and improved alkali resistance is exposed on the upper surface of the slider 20 which is a sliding surface for the magnetic recording medium.
The surplus portion on the upper side of the slider including the groove 21 is ground and removed in a later step. At this time, a part of the glass portion 18A is also ground and removed, but the glass of 18A remains in the groove 22 on the sliding surface. In FIG. 5, a portion indicated by an imaginary line is a portion to be ground and removed.

In FIG. 5, the glass rod 19 for fusion is set in the groove 21 with the glass portion having the low fusion temperature facing down.
On the contrary, the glass part 18B is on top and the glass part 18A is on top.
Regardless of the orientation of the glass rod 19 for fusing, the glass portion 18B is better than the head constituent member regardless of the orientation of the glass rod 19 for fusion. Since the wettability is good, fusion is performed in the same manner as above.

The magnetic head material in which the slider and the head chip were fused by filling the glass portion of the sliding surface of the magnetic head only with the glass rod having the same composition as the glass portion 18B was immersed in a cleaning liquid having a pH of about 11 for 1 hour. However, since this glass did not contain Bi ₂ O ₃ having an effect of improving alkali resistance, the fused glass portion was eluted into the cleaning liquid and a fatal step was generated on the surface. Therefore, the glass part 18
The glass having the composition B is not suitable for fusing the portion exposed on the surface of the magnetic head.

On the other hand, the magnetic head material fused at the same location using only the glass rod having the composition of the glass portion 18A contains Bi ₂ O ₃ in the fused glass, and therefore the step difference as described above is produced. Did not occur.

However, when fusing, the groove 22 is filled only with the glass rod having the composition of the glass portion 18A,
Although the problem of alkali resistance is solved, in order to fill the entire groove 22 with glass of this composition, the fusing temperature must be 580 ° C. At that time, it is used for joining the gap part of the head chip 23. Since the temperature is higher than the glass transition point Tg (570 in this case, 570 ° C) of the existing glass (41A in Fig. 13), the gap around the head chip is loosened and the position shifts, which drastically reduces the dimensional accuracy of the magnetic head. To do. Therefore, a glass having an optimum fusing temperature higher than Tg of the first fusing glass (gap bonding glass) such as the composition of the glass portion 18A is not suitable for the second and subsequent fusing.

Further, by preparing each glass rod of the composition of the glass portion 18A and the composition of the same 18B, setting both in the groove 21 and fusing at 560 ° C. Although it is possible to fabricate a head that makes the most of the advantages of, the productivity is poor and the setting work is very difficult.

On the other hand, in this example, glass rods having a plurality of compositions are united and fused as one glass rod for fusing, and the magnetic head material is produced while making the best use of the advantages of each glass composition. In addition, the fusion work is simple, the above-mentioned positional deviation does not occur, and there is no problem in alkali resistance. As a result, the manufactured magnetic head becomes highly reliable. In addition, the above-described inconvenience of using two kinds of glass rods by mistake does not occur. Further, it is not necessary to separately provide a glass supply groove corresponding to each composition glass.

6 to 7 are partial perspective views showing an outline of the manufacturing process of the magnetic head for a hard disk.

As shown in FIG. 6, a V-shaped groove 21 for setting the glass for fusing is provided on the upper surface of the slider material 20 made of calcium titanate, and the glass rod 19 for fusing is placed in the groove 21. Has become. Also, the slider material
As described above, the groove 22 for the head chip set is provided on the side surface of 20. Groove 22 for this head chip
The head chip 23 is set in each groove and heated to 560 ° C. in this state.

By this heating, as explained in FIG. 5,
The slider material 20 in which the head chip 23 is glass-fused is
In the next step, as shown in FIG.
The foot 23a of the head chip for facilitating the setting of the head chip 23 is cut and removed, and at the same time, the upper surface of the slider 20 is ground to be ground in the same position as the upper surface of the head chip 23.

In the next step, after chamfering or the like, as shown in FIG. 7, a portion of the upper surface of the slider 20 surrounded by an imaginary line is ground to finish the shape shown in FIG. And
In the same figure, one slider 20 (head chip) as shown in FIG.
(Including 23) is completed.

As described above, according to this embodiment,
In the conventional method, for example, the number of steps required for distinguishing the glass that appears on the sliding surface of the magnetic head from other glass and setting them separately can be eliminated. Further, in a head that performs bonding a plurality of times, the problems that the previously fused members are displaced and the problem that the unreliable glass is inevitably used for the sliding surface are also solved. It is extremely convenient for the core coupling of

Although the embodiments of the present invention have been described above, the above embodiments can be further modified based on the technical idea of the present invention. For example, as shown in FIG. 10, various shapes and configurations of the glass for fusing by uniting can be modified.

Two rod parallel type by A and B of FIG. 10 (a), double structure of core B and outer layer A of FIG. 10 (b), conical reverse overlapping type of FIG. 10 (c), (D) three rod bundle type, (e), (f) alternate arrangement type, etc.
And B respectively represent glass compositions having different characteristics (for example, high melting point and low melting point, large reaction with the core and prevention of reaction, transparent and opaque, large Tg and small Tg, etc.).

Each glass rod for fusing shown in FIG. 10 can be easily manufactured by using a mold as shown in FIG. Figure 11
In (a), the glass parts A manufactured in advance are set at intervals in the cavity of the mold 24, and a low melting point is set in the cavity part (portion indicated by phantom line) which is a space after that. A method of injecting the glass melt through the injection port 24a (in-mold method) may be used. The double-cavity mold 25 shown in FIG. 11B can be manufactured in the same manner. The glass rods for fusion bonding having other shapes shown in FIG. 10 can be easily manufactured in accordance with the respective methods according to the method of FIG. 3 or the method of FIG. 11 when the crucible of FIG. 4 is modified.

Further, for example, the extruding direction of the liquid glass raw material from the crucible may be an appropriate direction other than the direction shown in FIG. 3 within a range that is possible depending on the gas pressure and the self weight of the liquid glass raw material. The nozzle position may also be an appropriate position. Further, the structure, shape, arrangement, etc. of each component of the device may be variously changed.

Further, the glass for fusing may be composed of two kinds of glass parts, and may be composed of three kinds or more kinds. In addition to the rod-shaped glass parts as described above, a powdery or granular material is used. The structure may be integrated and integrated, or the whole shape may be an appropriate shape other than the rod shape.

Furthermore, the glass rod for fusing produced by the present invention is also suitable for use for purposes other than core bonding of the magnetic head (sealing of electronic devices, bonding of cathode ray tube panels and funnels, etc.). The result is obtained. In this case, it goes without saying that the composition of the glass rod for fusing can be a composition that exhibits properties that meet the purpose.

[0071]

In the glass for fusing according to the present invention, a plurality of glass parts having different compositions are integrated, so that a single fusing operation is performed to obtain a plurality of continuous fusing points. On the other hand, glass having a composition corresponding to these can be fused, and the fusion work can be easily performed. Moreover, it becomes unnecessary to manage the glass for fusing as in the case of using a plurality of kinds of glass for fusing separately and fusing, and no trouble is caused by this mismanagement.

Further, the glass for fusing according to the present invention is used when fusing at a plurality of consecutive points using a glass of a type suitable for a fusing point or at a temperature lower than the optimum fusing temperature of the original glass alone. It is particularly advantageous for use in the manufacture of magnetic heads when fusion is desired.

[Brief description of drawings]

FIG. 1 is a perspective view of a glass rod for fusing according to an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view of the glass rod manufacturing apparatus for fusion welding.

FIG. 3 is a schematic sectional view similar to FIG. 2 when a liquid glass raw material is extruded.

FIG. 4 is an enlarged perspective view of a crucible.

FIG. 5 is an enlarged perspective view of an essential part of a magnetic head for a hard disk showing an example of using the glass rod for fusion welding.

FIG. 6 is a perspective view of a main part showing an example of a manufacturing process of the magnetic head.

FIG. 7 is a perspective view of a main part showing a state in which a polishing step after fusion bonding is completed.

FIG. 8 is a perspective view of an essential part showing a state where the grinding process is completed.

FIG. 9 is a perspective view showing a completed state of the slider.

FIG. 10 is a perspective view of a glass rod for fusing according to another embodiment of the present invention.

FIG. 11 is a perspective view of a mold showing a procedure for manufacturing a glass rod for fusing by an insert molding method.

FIG. 12 is a perspective view of a magnetic head for a floppy disk.

FIG. 13 is a perspective view of a magnetic head core for a hard disk.

[Fig. 14] Fig. 14 is a perspective view showing a procedure for joining core materials by conventional rod-shaped glass.

FIG. 15 is a perspective view showing the joined core materials.

FIG. 16 is a schematic front view of a rod-shaped glass manufacturing apparatus used in a pulling wire drawing method according to a conventional example.

FIG. 17 is a schematic front view of a rod-shaped glass manufacturing apparatus used in a conventional draw-down wire drawing method.

[Explanation of symbols]

 1 ... Glass manufacturing apparatus for fusing 3A, 3B ... Crucible 3Aa, 3Ba ... Nozzle 4 ... Upper lid 5A, 5B ... Rotating shaft 6 ... Stopper mechanism 7 ... Motor 7A, 7B , 8A, 8B ... Bevel gear 9 ... Cooling mechanism 10 ... Fusing glass storage mechanism 11 ... Control mechanism 12 ... Heater 13 ... Gas supply pipes 14A, 14B ... Valve 15A, 15B ... Stirring arm 16 ... Spacer 17 ... Gas 18A, 18B, 28A, 28B ... Glass part 19, 29 ... Glass rod for fusion 20 ... Slider 21 ... Glass for fusion Groove for rod set 22 ... Groove for head chip set 23 ... Head chip 24, 25 ... Mold 118A, 118B ... Liquid glass raw material F ... Funnel-shaped tube

Claims (13)

[Claims] 1. A glass for fusing, in which a plurality of glass portions having different compositions are integrated. 2. The glass for fusing according to claim 1, wherein the plurality of portions differ from each other in the optimum fusing temperature. 3. The glass for fusing according to claim 1, wherein a plurality of portions have different compositions from each other, and thus exhibit different wettability with respect to a material to be fused at a fusing temperature. 4. The glass for fusing according to claim 1, which has a rod shape. 5. The glass for fusing according to claim 4, wherein each of the plurality of portions has a rod shape, and the plurality of portions are arranged side by side in the width direction and are joined to each other. 6. The fusing glass according to claim 1, which is fusing of a magnetic head constituent material. 7. When manufacturing the glass for fusing according to any one of claims 1 to 6, a plurality of containers each having a stirring means and a gas supply means, a stopper mechanism, and a control mechanism, Using a heating means for heating the plurality of containers, the liquid glass raw material having a different composition melted in each of the containers, by gas pressure and the self-weight of the liquid glass raw material, 5 ~ 150 cm / sec A method for producing glass for fusing, which comprises extruding from the openings of the respective containers at a speed of 1 to combine them with each other. 8. The method for producing glass for fusing according to claim 7, wherein the extruded liquid glass raw material is cooled by a cooling mechanism. 9. A container comprising a stirring means, a gas supply means, and an opening for pushing out the liquid glass raw material, a stopper mechanism for closing and releasing the opening, a heating means and a control mechanism. An apparatus for carrying out the method according to claim 7 or 8. 10. The apparatus according to claim 9, further comprising a cooling mechanism for cooling the extruded liquid glass raw material. 11. A method of manufacturing a magnetic head, which comprises using the glass for fusing according to claim 1 and fusing a constituent material of a magnetic head. 12. The method of manufacturing a magnetic head according to claim 11, wherein a glass for fusing is melted and filled in a gap between the magnetic head chip and a slider material protecting the magnetic head chip. 13. The method of manufacturing a magnetic head according to claim 11, wherein the gap between the magnetic cores is filled with glass for fusing.