Abstract A magnetic read/write head having a single gap is mounted to a carriage positionable to locate the head at selected tracks on a magnetic disk by means of a lead screw and stepping motor. The pitch of the lead screw requires a multiple number of steps to move the read/write head one track position. Control circuitry is provided whereby the read/write head is either in the read or the write mode. A write operation is performed by first switching into the read mode and moving the head to the desired track. The stepping motor is then operated to offset the head to the right of the desired track. The sector identification is read with the head in the offset position and immediately after reading the identification, the operation is switched into the write mode to perform a D.C. erase of the sector. Upon reaching the end of the sector, the operation switches to the read mode and during the remainder of the revolution, the stepping motor offsets the head to the left of the desired track. The erased sector is then relocated by reading the identification for that sector and the operation again switches into the write mode and the desired data is written into the sector over the previously recorded data, if any, with a write current, i.e., using non-return to zero recording, which upon recording the new data destroys the old data. The head is then returned to the nominal position, i.e., not offset, and the operation switches into the read mode so as to read the written data and verify that the data has been properly written.
A method for controlling the operation of a single gap magnetic transducer for reading and writing data in tracks on magnetic media comprising the steps of: positioning said transducer off-set to one side of the nominal track posiTion on said magnetic media to overlie a portion of said nominal track and a portion adjacent thereto; energizing said transducer in said off-set to one side position to erase data from said magnetic media; positioning said transducer off-set to the other side of said nominal track position, and energizing said transducer in said off-set to the other side position to write data on said magnetic media partly within said nominal track and partly adjacent thereto.
Claim 2
Independent Claim
113 words
A method for controlling the operation of a single gap magnetic transducer for reading and writing data in tracks on magnetic media comprising the steps of: positioning said transducer off-set to one side of the nominal track posiTion on said magnetic media to overlie a portion of said nominal track and a portion adjacent thereto; energizing said transducer in said off-set to one side position to erase data from said magnetic media; positioning said transducer off-set to the other side of said nominal track position, and energizing said transducer in said off-set to the other side position to write data on said magnetic media partly within said nominal track and partly adjacent thereto.
Claim 3
Dependent Claim
43 words
The method of claim 1 further comprising the steps of: positioning said transducer to said nominal track position on said magnetic media; operating said transducer in said nominal track position to read data recorded partly within said nominal track on said magnetic media.
Claim 4
Dependent Claim
162 words
Apparatus for controlling the operation of a single gap magnetic transducer for reading and writing data in tracks on magnetic media comprising: transducer positioning means for incrementally moving said transducer; control means connected to provide control signals for operating said transducer positioning means, said control means providing a first control signal to cause said positioning means to move said transducer off-set to the right of a nominal track position; and a second control signal to cause said positioning means to move said transducer off-set to the left of a nominal track position; and transducer control means for energizing said transducer positioned off-set to the right of said nominal track position to erase data on said magnetic media partly in said nominal track and partly in the area adjacent thereto and for energizing said transducer positioned off-set to the left of said nominal position to write data partly in said nominal track and partly in the area adjacent thereto on said magnetic media.
Claim 5
Dependent Claim
162 words
Apparatus for controlling the operation of a single gap magnetic transducer for reading and writing data in tracks on magnetic media comprising: transducer positioning means for incrementally moving said transducer; control means connected to provide control signals for operating said transducer positioning means, said control means providing a first control signal to cause said positioning means to move said transducer off-set to the right of a nominal track position; and a second control signal to cause said positioning means to move said transducer off-set to the left of a nominal track position; and transducer control means for energizing said transducer positioned off-set to the right of said nominal track position to erase data on said magnetic media partly in said nominal track and partly in the area adjacent thereto and for energizing said transducer positioned off-set to the left of said nominal position to write data partly in said nominal track and partly in the area adjacent thereto on said magnetic media.
Claim 6
Dependent Claim
55 words
The apparatus of claim 3 wherein said control means provides a third control signal to cause said positioning means to move said transducer to said nominal track position and said transducer control means causes said transducer positioned at said nominal track positioned to read data recorded partly within said nominal track on said magnetic media.
Claim 7
Dependent Claim
30 words
The apparatus of claim 3 wherein said transducer positioning means comprises: a stepping motor; and a lead screw carrying said transducer and connected to be driven by said stepping motor.