Vertical magnetic recording arrangement

Abstract

The present device provides a downstream magnetic shield which is integrally formed with a write pole section having a tip to make up a magnetic recording head. The shield and the write pole tip are located with small gap therebetween, so that magnetic flux which fringes from the magnetic write pole tip is intercepted by the shield. Accordingly such fringing flux does not pass through the recording medium, and hence if a data bit has been written into the recording medium its dipole identity will not be weakened by the fringing flux of a subsequent data bit being written into the magnetic recording medium. In addition, the magnetic recording medium is made up of a first layer of material having perpendicular uniaxial anisotropy and an underlying layer made of a material which has a low magnetic flux reluctance characteristic. Accordingly, the magnetic flux passes vertically through the first layer, along the second layer and finally passes vertically from the second layer through the first layer into the shield. The face of the shield is designed to be many times as large as the face of the write pole section so that the density of the flux from the tip is sufficient to effect a vertical recording while the density of the flux passing into the downstream magnetic shield is low and hence a previously recorded pattern is not reversed.

I claim: 
     
       1. An arrangement for effecting vertical magnetic recording of information comprising in combination: movable magnetizable recording means formed to have first and second layers which lie substantially parallel to the movement of said magnetizable recording means, said first layer comprised of magnetizable material which is characterized by perpendicular uniaxial anisotropy and said second layer comprised of material characterized by low magnetic reluctance, said magnetizable recording means arranged to be moved in a downstream direction; magnetic recording head means including magnetic flux generating means, formed to have a write pole section and a downstream magnetic shield section which is integrally connected to said write pole section so that magnetic flux can readily pass, bi-directionally, through said write pole section and said downstream magnetic shield section; said downstream magnetic shield section formed and disposed to have a relatively large face lying in close proximity to said first layer; said write pole section fashioned, while extending in an upstream direction from said downstream magnetic shield section, to form a partial loop configuration defining an opening and ending in a pole tip which is disposed to lie in close proximity to said first layer so that the magnetic flux passing into and alternatively out of said write pole section will pass from said first layer through said pole tip and alternatively from said pole tip into said first layer, said write pole section being further formed and disposed such that a small gap having a sufficiently small width is formed between said pole tip and said downstream magnetic shield section so that, when said pole tip has magnetic flux passing therethrough, fringing flux in the downstream direction will substantially pass across said small gap into said downstream magnetic shield face without passing through said first layer, and whereby the remainder of said magnetic flux passing through said pole tip passes substantially vertically through said first layer into said second layer, substantially parallel to and through said second layer, and substantially vertically from said second layer through said first layer into said downstream magnetic shield face, thereby effecting vertical magnetic recording of information in said first layer. 
     
     
       2. An arrangement for effecting vertical magnetic recording according to claim 1 wherein there is a distance from where said magnetic flux leaves said pole tip and enters said second layer and wherein said distance is G and wherein the width of said small gap is between G/2 and 2G. 
     
     
       3. An arrangement for effecting vertical magnetic recording according to claim 1 wherein said magnetic flux generating means is a wire coil which in part passes through the opening in said partial loop configuration of said write pole section. 
     
     
       4. An arrangement for effecting vertical magnetic recording according to claim 1 wherein said write pole tip defines a track on said magnetic recording means and wherein there is further included side magnetic shield means which are disposed to lie in close proximity to said write pole section along at least one adjacent track position to form at least one side gap therebetween to enable said side shield means to intercept magnetic flux which is fringing from said magnetic write pole tip in the direction of tracks adjacent to said track defined by the passage of said magnetic recording means relative to said write pole tip. 
     
     
       5. An arrangement for effecting magnetic recording according to claim 4 wherein said side magnetic shield means includes first and second side magnetic shield means each of which is disposed to lie on opposite sides of, and in close proximity to, said write pole section to respectively form first and second gaps between said first and second side magnetic shield means and said write pole section to enable said first and second side shield means to intercept magnetic flux .[.while.]. .Iadd.which .Iaddend.is fringing from said magnetic write pole tip in the direction of tracks adjacent to said track defined by the extension of said write pole tip onto said magnetic recording means. .Iadd. 
     
     
       6.  A magnetic transducing head device, operable in conjunction with and from a preferred side of a layered vertical recording medium arranged to be moved in a downstream direction for effecting vertical recording of bits of information in tracks thereon, the device comprising magnetic flux generating means including   a write pole section, and   a downstream magnetic shield section which is integrally connected to said write pole section so that magnetic flux can readily pass through said write pole section and said downstream magnetic shield section,   said downstream magnetic shield section formed and disposed to have a relatively large face defining an air bearing surface which can be operated in close proximity to said preferred side of said medium,   said write pole section and said downstream magnetic shield section being constructed so that said write pole section is disposed in an upstream direction with respect to said downstream magnetic shield section so that said write pole section and said downstream magnetic shield section form a partial loop configuration that defines an opening between said write pole section and said downstream magnetic shield section, said write pole section ending in a pole tip which is disposed to be operated in close proximity to said medium so that the magnetic flux passing through said write pole section will pass from said pole tip into said medium,   said opening defining a gap at a midsection of said write pole section and said downstream magnetic shield section and a relatively smaller gap between said pole tip and said downstream magnetic shield section, said smaller gap having a sufficiently small width so that, when said pole tip has magnetic flux passing therethrough, fringing flux in the downstream direction will be substantially directed to pass from said pole tip across said smaller gap into said downstream magnetic shield, such that substantially all of the remainder of said magnetic flux is presented for passing through said pole tip substantially vertically into said medium and then to said downstream magnetic shield face, and   whereby sharply defined bits of information may be vertically recorded at said pole tip in tracks on said medium. .Iaddend. .Iadd.   
     
     
       7.  The device of claim 6 wherein said magnetic flux generating means is a wire coil which in part passes through the opening in said partial loop configuration. .Iaddend. .Iadd. 
     
     
       8.  The head device of claim 6 further including side magnetic shield means disposed to lie in close proximity to said write pole section along at least one track adjacent to a track to be written on said medium at said pole tip to form at least one side gap between said side shield means and said write pole section to enable said side shield means to intercept magnetic flux which is fringing from said pole tip in the direction of said at least one adjacent track. .Iaddend. .Iadd. 
     
     
       9.  The head device of claim 8 wherein said side shield means includes first and second side magnetic shield means each of which is disposed to lie on opposite side of, and in close proximity to, said write pole section to respectively form first and second gaps between said first and second side magnetic shield means and said write pole section to enable said first and second side shield means to intercept magnetic flux from said magnetic write pole tip in the direction of tracks adjacent to a track to be written at said pole tip on said medium. .Iaddend. .Iadd. 
     
     
       10.  The device of claim 6 wherein said write pole section is constructed with a bowed region to define said partial loop configuration. .Iaddend. .Iadd. 
     
     
       11.  A magnetic transducing head device having at least one pole for effecting vertical recording of magnetic transitions on and from a preferred side of a layered vertical magnetic recording medium arranged to be moved in a downstream direction, the device comprising a write pole terminating in a write pole tip,   a downstream shield integrally connected to the write pole and having a large shield tip area relative to the area of the write pole tip,   the write pole cooperating with the downstream shield to engage flux from a write flux source,   the write pole tip configured to present write flux from the write flux source to the medium for recording information on the medium, and   the write pole and said downstream shield being constructed to define a gap between them, said gap being smaller in the area of the write pole tip and the downstream shield tip than it is in an area closer to where the downstream shield is integrally connected to said write pole,   said gap between the write pole tip and the downstream shield tip being sufficiently small to substantially transfer to the downstream shield downstream fringing flux emanating from the write pole tip to minimize presentation of downstream fringing flux to the medium when presenting write flux from the pole tip to the medium for recording information on the medium, whereby a write field gradient generated by the write flux in the recording medium is increased and recorded transitions are sharper, as a result of such minimization. .Iaddend. .Iadd.   
     
     
       12.  The device of claim 11 wherein the write flux source is a wire coil, that passes through at least a portion of said gap. .Iaddend. .Iadd. 
     
     
       13.  The head device of claim 11 further including side magnetic shield means disposed to lie in close proximity to the write pole section along at least one track adjacent to a track to be written on the medium at the pole tip to form at least one side gap therebetween to enable the side shield means to intercept magnetic flux fringing from the pole tip in the direction of the at least one adjacent track. .Iaddend. .Iadd. 
     
     
       14.  The head device of claim 13 wherein the side shield means includes first and second side magnetic shield means each of which is disposed to lie on opposite sides of, and in close proximity to, the write pole section to respectively form first and second gaps between the first and second side magnetic shield means and the write pole section to enable the first and second side shield means to intercept magnetic flux from the magnetic write pole tip in the direction of tracks adjacent to a track to be written at the pole tip on the medium. .Iaddend. .Iadd. 
     
     
       15.  The device of claim 11 wherein said write pole is constructed with a bowed region to define said gap and said smaller gap. .Iaddend. .Iadd. 
     
     
       16.  A magnetic transducing head device, operable in conjunction with and from a preferred side of a layered vertical recording medium arranged to be moved in a downstream direction for effecting vertical recording of bits of information in tracks thereon, comprising magnetic flux generating means, including   a write pole section, and   a downstream magnetic shield section which is integrally connected to said write pole section so that magnetic flux can readily pass through said write pole section and said downstream magnetic shield section,   said downstream magnetic shield section formed and disposed to have a relatively large face defining an air bearing surface which can be operated in close proximity to said preferred side of said medium, said write pole section fashioned, while extending in an upstream direction from said downstream magnetic shield section, to form a partial loop configuration defining an opening and ending in a pole tip which is disposed to be operated in close proximity to said medium so that the magnetic flux passing through said write pole section will pass from said pole tip into said medium,   said write pole section being further formed and disposed with a bowed out midsection with a small gap having a sufficiently small width formed between said pole tip and said downstream magnetic shield section so that, when said pole tip has magnetic flux passing therethrough, fringing flux in the downstream direction will be substantially directed to pass from the side of said pole tip across said small gap into said downstream magnetic shield, such that substantially all of the remainder of said magnetic flux is presented for passing through said pole tip substantially vertically into said medium and then to said downstream magnetic shield face,   whereby sharply defined bits of information may be vertically recorded at said pole tip in tracks on said medium, and further including side magnetic shield means disposed to lie in close proximity to said write pole section along at least one track adjacent to a track to be written on said medium at said pole tip to form at least one side gap between said side shield means and said write pole section to enable said side shield means to intercept magnetic flux which is fringing from said pole tip in the direction of said at least one adjacent track. .Iaddend. .Iadd.17. The device of claim 16 wherein said side shield means includes first and second side magnetic shield means each of which is disposed to lie on opposite sides of, and in close proximity to, said write pole section to respectively form first and second gaps between said first and second side magnetic shield means and said write pole section to enable said first and second side shield means to intercept magnetic flux from said magnetic write pole tip in the direction of tracks adjacent to a track to be written at said pole tip on said medium. .Iaddend. .Iadd.18. A magnetic head having at least one pole for effecting downstream vertical recording of magnetic transitions on a layered vertical magnetic recording medium via a write field gradient comprising   a write pole terminating in a write pole tip,   a downstream shield integrally connected to the write pole and having a large shield tip area relative to the area of the write pole tip,   the write pole cooperating with the downstream shield to engage flux from a write flux source,   the write pole tip configured to present write flux from the write flux source to the medium for recording information on the medium,   the write pole proximally coupled to the downstream shield to substantially capture downstream fringing flux emanating from the write pole to minimize presentation of downstream fringing flux to the medium when presenting write flux from the pole tip to the medium for recording information on the medium, whereby the write field gradient at the pole tip is increased and recorded transitions are sharper, as a result of such minimization, and   further including side magnetic shield means disposed to lie in close proximity to the write pole section along at least one track adjacent to a track to be written on the medium at the pole tip to form at least one side gap therebetween to enable the side shield means to intercept magnetic flux fringing from the pole tip in the direction of the at least   
     
     
        one adjacent track. .Iaddend. .Iadd.19.  The head of claim 18 wherein the side shield means includes first and second side magnetic shield means each of which is disposed to lie on opposite sides of, and in close proximity to, the write pole section to respectively form first and second gaps between the first and second side magnetic shield means and the write pole section to enable the first and second side shield means to intercept magnetic flux from the magnetic write pole tip in the direction of tracks adjacent to a track to be written at the pole tip on the medium. .Iaddend. 
     
     
        .Iadd.20.  An arrangement for effecting vertical magnetic recording of information comprising in combination: movable magnetizable recording means formed to have first and second layers which lie substantially parallel to the movement of said magnetizable recording means, said first layer comprised of magnetizable material which is characterized by perpendicular uniaxial anisotropy and said second layer comprised of material characterized by low magnetic reluctance, said magnetizable recording means arranged to be moved in a downstream direction;   magnetic recording head means including magnetic flux generating means, formed to have a write pole section and a downstream magnetic shield section which is integrally connected to said write pole section so that magnetic flux can readily pass, bidirectionally, through said write pole section and said downstream magnetic shield section;   said downstream magnetic shield section formed and disposed to have a relatively large face lying in close proximity to said first layer;   said write pole section and said downstream magnetic shield section being constructed so that said write pole section is disposed in an upstream direction with respect to said downstream magnetic shield section so that said write pole section and said downstream magnetic shield section form a partial loop configuration that defines an opening between said write pole section and said downstream magnetic shield section, said write pole section ending in a pole tip which is disposed to lie in close proximity to said first layer so that the magnetic flux passing into and alternatively out of said write pole section will pass from said first layer through said pole tip and alternatively from said pole tip into said first layer,   said opening defining a small gap between said pole tip and said downstream magnetic shield section that has a sufficiently small width so that, when said pole tip has magnetic flux passing therethrough, fringing flux in the downstream direction will substantially pass across said small gap into said downstream magnetic shield section without passing through said first layer, and whereby the remainder of said magnetic flux passing through said pole tip passes substantially vertically through said first layer into said second layer, substantially parallel to and through said second layer, and substantially vertically from said second layer through said first layer into said downstream magnetic shield face, thereby effecting vertical magnetic recording of information in said first layer. .Iaddend.   
     
     
        .Iadd.21.  The device of claim 20 wherein said write pole section is constructed with a bowed region to define said partial loop configuration. 
     
     
        .Iaddend. .Iadd.22.  An arrangement for effecting vertical magnetic recording of information comprising in combination: movable magnetizable recording means formed to have first and second layers which lie substantially parallel to the movement of said magnetizable recording means, said first layer comprised of magnetizable material which is characterized by perpendicular uniaxial anisotropy and said second layer comprised of material characterized by low magnetic reluctance, said magnetizable recording means arranged to be moved in a downstream direction;   magnetic recording head means including magnetic flux generating means, formed to have a write pole section and a downstream magnetic shield section which is integrally connected to said write pole section so that magnetic flux can readily pass, bidirectionally, through said write pole section and said downstream magnetic shield section;   said downstream magnetic shield section formed and disposed to have a relatively large face lying in close proximity to said first layer;   said write pole section and said downstream magnetic shield section being constructed so that said write pole section is disposed in an upstream direction with respect to said downstream magnetic shield section so that said write pole section and said downstream magnetic shield section form a partial loop configuration that defines a first gap between said write pole section and said downstream magnetic shield section, said write pole section ending in a pole tip which is disposed to lie in close proximity to said first layer so that the magnetic flux passing into and alternatively out of said write pole section will pass from said first layer through said pole tip and alternatively from said pole tip into said first layer,   said partial loop configuration defining a second gap of narrower width than said first gap between said pole tip and said downstream magnetic shield section, said width of said second gap being sufficiently small such that when said pole tip has magnetic flux passing therethrough, fringing flux in the downstream direction will substantially pass across said small gap into said downstream magnetic shield without passing through said first layer, and whereby the remainder of said magnetic flux passing through said pole tip passes substantially vertically through said first layer into said second layer, substantially parallel to and through said second layer, and substantially vertically from said second layer through said first layer into said downstream magnetic shield face, thereby effecting vertical magnetic recording of information in said first   
     
     
        layer. .Iaddend. .Iadd.23.  The device of claim 22 wherein said write pole section is constructed with a bowed region to define said partial loop configuration. .Iaddend.