Abstract:
A magnetic head unit includes a head chip, a plurality of magnetic head elements, a pair of side chips and a base member. The head chip has a first face. The plurality of magnetic head elements are arranged on the first face of the head chip. The pair of side chips sandwich the head chip from both sides of the first face thereof. The base member holds the head chip and the side chips. The head chip, the side chips and the base members are joined to each other by conductive resin.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    The present invention relates to a magnetic head unit and a method for fabricating the same and, in particular, relates to a magnetic head unit and a method for fabricating the same in which respective members thereof are joined by conductive resin.  
           [0002]    As a magnetic head device for recording a signal on and reproducing a signal from a magnetic recording tape, a so-called multi-channel type magnetic head device is known in which a plurality of magnetic head elements as shown in FIGS. 4A and 4B are arranged. Such a related magnetic head device  50  is configured in a manner that magnetic head assemblies  100  shown in FIG. 4B are joined to each other by adhesive resin.  
           [0003]    The magnetic head unit  100  is configured in a manner that the magnetic gaps  102   a  of a plurality of magnetic head elements  102  are arranged in parallel so as to face on a sliding face  101  on which a magnetic recording tape is slid, whereby the plurality of magnetic gaps  102   a  record a signal on and reproduce a signal from the magnetic recording tape. The magnetic head unit  100  is formed by a head chip  103  having a plurality of the magnetic head elements  102 , a protection chip  104  disposed so as to oppose to the one side face of the head chip  103 , a pair of side chips  105  disposed so as to sandwich the head chip  103  and the protection chip  104  therebetween, a base member  106  on which the head chip  103  and the side chips  105  are attached, and a flexible printed wiring board  107  coupled to the terminal portions  102   b  of the magnetic head elements  102 .  
           [0004]    Each of the head chip  103 , the protection chip  104 , the side chips  105  and the base member  106  is formed by ceramics material such as alumina-titanium carbide (Al203-TiC), for example.  
           [0005]    The head chip  103 , the side chips  105  and the base member  106  are joined from one another by adhesive resin in a manner that the side face  103   a  of the head chip  103  is abutted against the side face  105   a  of the side chip, the side face  103   b  of the head chip  103  is abutted against the side face  105   b  of the side chip, and the lower face  13   a  of the head chip  103  and the lower faces  105   c  of the side chips  105  are abutted against the upper face  106   a  of the base member  106 .  
           [0006]    Next, the pair of the magnetic head assemblies  100  thus configured are joined to each other by adhesive resin in a manner that joining faces  51  each formed by the head chip  103 , the side chips  105  and the base member  106  are abutted to each other. Then, the magnetic head device  50  is completed by forming a center groove  52  and a pair of side grooves  53  through the processing of the sliding face.  
           [0007]    However, the related magnetic head device  50  is configured by the magnetic head assemblies  100  each formed by many parts and the adhesive resin is used at the time of joining the head chip  103 , the side chips  105  and the base member  106  constituting the magnetic head unit  100 , so that the portions among the respective members, that is, the head chip  103 , the side chips  105  and the base member  106  are insulated. Thus, the magnetic head device  50  has a problem that the magnetic head elements  102  may be broken due to static electricity generated at the time of processing the sliding face. In order to eliminate such a problem, it is required to separately provide an earth structure for earthing or grounding static electricity generated among the head chip  103 , the side chips  105  and the base member  106 . However, in the fabricating process of the magnetic head device, this process of providing the earth structure becomes a reason for degrading the fabricating efficiency since this process is complicated.  
           [0008]    Also, in the related magnetic head device  50 , the base member  106  as well as the head chip  103  having the sliding face on which a magnetic recording tape slides, the protection chip  104  and the side chips  105  are formed by high-hardness ceramics material, so that there arises a problem that the magnetic head device is expansive and degraded in processing efficiency or properties thereof.  
         SUMMARY OF THE INVENTION  
         [0009]    It is therefore an object of the present invention to provide a magnetic head device and a method for fabricating the same which can eliminate the earth structure for earthing or grounding static electricity which is generated at the main body of the magnetic head device and becomes a cause of a problem.  
           [0010]    Also, it is therefore an object of the present invention to provide a magnetic head device and a method for fabricating the same which can improve the processing efficiency or properties of the magnetic head device and reduce the manufacturing cost thereof.  
           [0011]    In order to achieve the above object, according to the present invention, there is provided a magnetic head unit comprising:  
           [0012]    a head chip, having a first face which is provided with a plurality of magnetic gaps;  
           [0013]    a pair of side chips, which sandwich the head chip from both sides of the first face thereof; and  
           [0014]    a base member, which holds the head chip and the side chips,  
           [0015]    wherein the head chip, the side chips and the base members are joined to each other by conductive resin.  
           [0016]    Thus, the magnetic head unit is kept to hold static-electricity resistance properties even if an earth line for grounding static electricity which is generated at the magnetic unit main body and becomes a cause of a problem is eliminated. Further, the working efficiency for manufacturing the magnetic head unit can be improved and the manufacturing cost of the magnetic head device can be reduced.  
           [0017]    According to the present invention, there is also provided a method for fabricating a magnetic head unit, comprising the steps of:  
           [0018]    providing a head chip which has a first face provided with a plurality of magnetic gaps;  
           [0019]    providing a pair of side chips;  
           [0020]    providing a base member;  
           [0021]    sandwiching the head chip from both sides of the first face thereof by the pair of side chips;  
           [0022]    holding the head chip and the side chips on the base member; and  
           [0023]    joining the head chip, the side chips and the base member to each other by conductive resin to form the magnetic head unit.  
           [0024]    Preferably, the method further comprising the step of joining at least two head unit formed in the joining step to each other by the conducive resin.  
           [0025]    In the above method, the magnetic head unit is kept to hold static-electricity resistance properties even if an earth line for grounding static electricity which is generated at the magnetic head main body and becomes a cause of a problem is eliminated. Further, the working efficiency for manufacturing the magnetic head unit can be improved and the manufacturing cost of the magnetic head unit can be reduced.  
           [0026]    Preferably, the base member is formed by material with Vickers hardness equal to or less than 1500.  
           [0027]    In the above method, processing efficiency or properties of the magnetic head unit can be improved and the manufacturing cost thereof can be reduced. Further, the magnetic head unit itself can be light-weighted.  
           [0028]    Preferably, the base member is formed by resin material.  
           [0029]    In the above method, processing efficiency or properties of the magnetic head unit can be improved and the manufacturing cost thereof can be reduced. Further, the magnetic head unit itself can be light-weighted.  
           [0030]    According to the present invention, there is also provided a magnetic head unit comprising:  
           [0031]    a head chip, having a first face which is provided with a plurality of magnetic gaps;  
           [0032]    a pair of side chips, which sandwich the head chip from both sides of the first face thereof; and  
           [0033]    a base member, which holds the head chip and the side chips,  
           [0034]    wherein the base member is formed by material with Vickers hardness equal to or less than 1500.  
           [0035]    Preferably, the base member is formed by low-hardness ceramics.  
           [0036]    Preferably, the low-hardness ceramics is CaTiO3 or BaTiO.  
           [0037]    Preferably, the base member is formed by ferrite.  
           [0038]    In the above configurations, processing efficiency or properties of the magnetic head unit can be improved and the manufacturing cost thereof can be reduced. Further, the magnetic head unit itself can be light-weighted.  
           [0039]    Preferably, the base member is formed by resin material.  
           [0040]    Preferably, the head chip, the side chips and the base member are joined to each other by conductive resin.  
           [0041]    In the above configurations, processing efficiency or properties of the magnetic head unit can be improved and the manufacturing cost thereof can be reduced. Further, the magnetic head unit itself can be light-weighted. In this case, preferably, the head chip, the side chips and the pedestal are joined from one another by conductive resin. Thus, static electricity generated at the magnetic head unit can be grounded efficiently.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0042]    The above objects and advantages of the present invention will become more apparent by describing in detail preferred exemplary embodiments thereof with reference to the accompanying drawings, wherein:  
         [0043]    [0043]FIG. 1 is a perspective view showing the configuration of the magnetic head unit of a magnetic head device according to an embodiment of the invention;  
         [0044]    [0044]FIG. 2 is a perspective view showing the external appearance of the magnetic head unit of the magnetic head device according to the embodiment of the invention;  
         [0045]    [0045]FIG. 3 is a perspective view showing the external appearance of the magnetic head device according to the embodiment of the invention;  
         [0046]    [0046]FIG. 4A is a perspective view showing the external appearance of a related magnetic head device; and  
         [0047]    [0047]FIG. 4B is a perspective view showing the external appearance of a related magnetic head unit. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0048]    An embodiment of the invention will be explained in detail with reference to FIGS.  1  to  3 . FIG. 1 shows the configuration of the magnetic head unit of the magnetic head device according to the invention, FIG. 2 shows the external appearance of the magnetic head unit, and FIG. 3 shows the entire appearance of the magnetic head device according to the invention. As shown in FIGS. 1 and 2, the magnetic head unit  10  of the magnetic head device  1  shown as an embodiment of the invention is configured in a manner that the magnetic gaps  12   a  of a plurality of magnetic head elements  12  are arranged in parallel so as to face on a sliding face  11  on which a magnetic recording tape slides, whereby the plurality of magnetic head elements  12  record a signal in and reproduce a signal from the magnetic recording tape. The magnetic head unit  10  is formed by a head chip  13  having a plurality of the magnetic head elements  12 , a protection chip  14  disposed so as to oppose to the one side face of the head chip  13 , a pair of side chips  105  disposed so as to sandwich the head chip  13  and the protection chip  14  therebetween, a base member  16  on which the head chip  13  and the side chips  15  are attached, and a flexible printed wiring board  17  coupled to the terminal portions  12   b  of the magnetic head elements  12 .  
         [0049]    The head chip  13 , the side chips  15  and the base member  16  are joined from one another by conductive resin  18  in a manner that the side face  13   a  of the head chip  13  is abutted against the side face  15   a  of the side chip, the side face  13   b  of the head chip  13  is abutted against the side face  15   b  of the side chip, and the lower face  13   c  of the head chip  13  and the lower faces  15   c  of the side chips  15  are abutted against the upper face  16   a  of the base member  16 . The conductive resin  18  is high molecular or high polymer material with a high dielectric constant. For example, polythiazyl etc. may be employed as the conductive resin of inorganic polymer and halide polyacetylene etc. may be employed as the conductive resin of organic polymer.  
         [0050]    In the magnetic head device  1 , each of the magnetic head elements  12  is formed on a ceramic board and provided with a reproducing portion which is formed by a not-shown magnetoresistive element etc. and an electromagnetic induction type recording portion formed by the method such as the sputtering method, the photo-etching method etc. The head chip  13  is provided with the magnetic head elements  12  which are formed by ceramic material such as alumina-titanium carbide (Al203-TiC) and disposed in parallel on the one faced side of the head chip.  
         [0051]    The protection chip  14  is formed by ceramic material such as alumina-titanium carbide (Al203-TiC) and configured in a shape sufficient for covering an area of the head chip  13  except for the terminal portions  12   b  of the magnetic head elements  12 .  
         [0052]    The side chips  15  constituting the sliding face  11  on which the magnetic recording tape slides are formed by ceramic material such as alumina-titanium carbide (Al203-TiC) like the head chip. The pair of the side chips  15  are provided with notched portions  19  on their faces sandwiching the head chip  13  therebetween. Each of the notched portions  19  is formed on the face of the side chip which abuts against the base member  16  so as to leave the main face of the side chip which serves as a sliding face of the side chip  15 . In other words, the pair of the side chips  15  are provided with the notched portions  19  at their portions sandwiching the terminal portions  12   b  of the magnetic head elements  12  therebetween.  
         [0053]    The base member  16  is formed by material with Vickers hardness equal to or less than 1500, that is, low-hardness ceramics such as CaTiO3 or BaTiO which is excellent in processing efficiency or properties and is cheap as compared with Al203-TiC, for example. The base member  16  is provided with a concave groove  20  having a width corresponding to the width of the flexible printed wiring board. Thus, the flexible printed wiring board  17  can be positioned accurately within the concave groove  20  of the base member  16 . Alternatively, the base member  16  may be formed by ferrite or resin material. When the base member is formed by resin material, since the portions among the head chip  13 , the side chips  15  and the base member  16  are insulated, the head characteristics may be degraded due to static electricity. Thus, in this case, it is preferable to join the head chip  13 , the side chips  15  and the base member  16  by conductive resin.  
         [0054]    The magnetic head device  1  is formed in the following manner. That is, the head chip  13 , the protection chip  14 , the side chips  15  and the base member  16  are combined and joined from one another by means of the conductive resin  18  as described above thereby to form the magnetic head unit  10 . Then, a pair of the magnetic head assemblies  10  are abutted to each other at their joining faces  2  each constituted by the head chip  13 , the protection chip  14 , the side chips  15  and the base member  16  and then joined to each other by means of the conductive resin  18 . Then, the sliding face  11  is processed in a cylindrical shape, and a center groove  3  and a pair of side grooves  4  are formed by processing the sliding face. Thereafter, the flexible printed wiring board  17  is attached to the magnetic head assemblies. In this case, since the flexible printed wiring board  17  is disposed along the concave groove  20  formed at the base member  16 , the flexible printed wiring board can be positioned quite accurately. Then, the flexible printed wiring board  17  and the terminal portions  12   b  of the magnetic head elements  12  are coupled by the wire bonding in a state that the flexible printed wiring board  17  is positioned.  
         [0055]    As described above, since the low-hardness material which can be scraped easily is used as the material of the base member  16 , the processing efficiency or properties of the magnetic head device can be improved and the manufacturing cost thereof can be reduced. Further, the magnetic head device itself can be light-weighted.  
         [0056]    Also, the magnetic head device  1  is kept to hold static-electricity resistance properties even if the earth structure for eliminating static electricity which degrades the head characteristics is not provided. Further, the working efficiency for manufacturing the magnetic head device  1  can be improved and the manufacturing cost of the magnetic head device can be reduced.  
         [0057]    The invention is not limited to the embodiment and, of course, various modification may be made within a range not departing from the gist of the invention.