Magnetic recording medium manufacturing apparatus
View Patent ↗Provided is a magnetic recording medium manufacturing apparatus capable of forming a lubricant film with a uniform thickness on the surface of a magnetic recording medium. The magnetic recording medium manufacturing apparatus includes a hanger mechanism ( 2 ) that is inserted into a central hole ( 100 a ) of a magnetic recording medium ( 100 ) and supports the magnetic recording medium ( 100 ) in a suspended state and a lifting mechanism ( 3 ) that lifts and lowers one of the hanger mechanism ( 2 ) and the dip tank ( 1 ) relative to the other. The hanger mechanism ( 2 ) includes supporting plates ( 4 a, 4 b ) that have upper ends coming into contact with an inner circumferential portion of the magnetic recording medium ( 100 ) and baffle plates ( 7 a, 7 b ) that have upper ends disposed below the upper ends of the supporting plates ( 4 a, 4 b ) such that a gap is formed between the upper end of the baffle plate and the inner circumferential portion of the magnetic recording medium ( 100 ) and are provided so as to face the supporting plates ( 4 a, 4 b ).
1. A method of manufacturing a magnetic recording medium comprising:
dipping a disk-shaped magnetic recording medium with a central hole into a dip tank filled with a liquid lubricant while inserting a hanger mechanism into the central hole of the magnetic recording medium to support the magnetic recording medium in a suspended state; and
taking out the magnetic recording medium from the dip tank in a vertical direction to form a lubricant film on a surface of the magnetic recording medium,
wherein the hanger mechanism includes a supporting plate located within the central hole, and including an upper end having a groove portion into which an inner circumferential portion of the magnetic recording medium is fitted and a baffle plate that is provided within the central hole and facing one side of the supporting plate so as to be arranged in parallel to the supporting plate,
an upper end of the baffle plate is disposed below the upper end of the supporting plate such that a first gap is formed between the upper end of the baffle plate and the inner circumferential portion of the magnetic recording medium,
a liquid pool being formed in a second gap between the inner circumferential portion of the magnetic recording medium and a surface of the groove portion of the supporting plate by the surface tension of the liquid lubricant as the magnetic recording medium is taken out from the dip tank, wherein a thickness of the liquid pool is gradually reduced as the magnetic recording medium is being taken out from the dip tank and at some point the liquid pool is cut and a part of the liquid pool connected to the inner circumferential portion of the magnetic recording medium is moved to a level of the liquid lubricant along the inner circumferential portion of the magnetic recording medium, and
the upper end of the baffle plate is positioned so that it is higher than a height of the liquid level of the liquid lubricant in the dip tank just before the liquid pool is cut and moved up to the level of the liquid lubricant.
2. The method of manufacturing a magnetic recording medium as claimed in claim 1 ,
wherein the hanger mechanism includes a pair of supporting plates located within the central hole, having inner sides facing one another and having upper ends which come into contact with the inner circumferential portion of the magnetic recording medium and a pair of baffle plates that are provided within the central hole so as to face outer sides of the pair of supporting plates and so as to be arranged in parallel to the supporting plates.
3. The method of manufacturing a magnetic recording medium as claimed in claim 1 ,
wherein a slit is vertically formed in the bottom of the groove portion of the supporting plate.
4. The method of manufacturing a magnetic recording medium as claimed in claim 1 ,
wherein the hanger mechanism supports a plurality of magnetic recording media arranged in a line.