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US3769464A
Expired / Lapsed
US
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Method and apparatus for maintaining alignment between a tape recorder head and a track of recorded material on a magnetic tape
Assignee: Ricoh Co Ltd
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Filing: 1971-12-20
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Granted: 1973-10-30
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Expires: 1991-12-20
Abstract
Abstract Apparatus and method whereby a magnetic reproducing head comprising a head element for controlling the vertical position of the head relative to a track of recorded material on a magnetic tape and a head element for reproducing the recorded material and disposed on a pivotal lever maintained in a balanced position by the electromagnetic force of electromagnetic means and the biasing force of a spring can be kept in alignment with the track of recorded material at all times. A tracking error produces a change in the relative positions of the track of recorded material and the vertical position control head element and causes a magnetic variation to occur. The magnetic variation is detected by the vertical position control head element which accordingly controls the electromagnetic force of the electromagnetic means so as to bring the reproducing head back into alignment with the track of recorded material. When the magnetic tape used is an endless tape carrying multiple tracks of recorded material which are continuous with one another through an inclined track portion, it is possible to automatically switch the reproducing head from one track to another as the electromagnetic force of the electromagnetic means is increased when the position control head element is brought into alignment with the inclined track portion.
Inventors
- 👤 S Jinsenji
- 👤 T Kawata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 12:38
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/48; G11B5/58; G11B5/584; G11B15/00; G11B15/02; G11B15/12
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
183 words
Apparatus for maintaining a normal vertical alignment position between a magnetic head and a recording track of magnetically recorded information on a magnetic tape transported horizontally with respect to the head comprising: a vertical position control head element affixed to the head and disposed at a defined vertical position with respect to the track when the head is at said normal vertical alignment position with respect to the track, said control head element being responsive to a defined vertical displacement of the control head element from said defined vertical position with respect to the track to generate a control signal varying as a function of the degree and sense of said vertical displacement, said control head element being distinct from said magnetic head, and said control signal being distinct and different from any signals provided by said magnetic head; and head positioning means connected to said magnetic head and connected to receive said control signal and responsive to defined variations in said control signals to move the head toward said normal vertical alignment position with respect to the track of magnetically recorded information.
Claim 2
Dependent Claim
183 words
Apparatus for maintaining a normal vertical alignment position between a magnetic head and a recording track of magnetically recorded information on a magnetic tape transported horizontally with respect to the head comprising: a vertical position control head element affixed to the head and disposed at a defined vertical position with respect to the track when the head is at said normal vertical alignment position with respect to the track, said control head element being responsive to a defined vertical displacement of the control head element from said defined vertical position with respect to the track to generate a control signal varying as a function of the degree and sense of said vertical displacement, said control head element being distinct from said magnetic head, and said control signal being distinct and different from any signals provided by said magnetic head; and head positioning means connected to said magnetic head and connected to receive said control signal and responsive to defined variations in said control signals to move the head toward said normal vertical alignment position with respect to the track of magnetically recorded information.
Claim 3
Dependent Claim
57 words
Apparatus as in claim 1 wherein said head positioning means includes an electromagnetic means having a plunger and responsive to said control signal to move the plunger along a distance defined by the magnitude of the control signal, and means connecting the plunger and the head to move the head vertically in response to said plunger movement.
Claim 4
Dependent Claim
64 words
Apparatus as in claim 2 wherein said plunger moves in a defined direction in response to an increase in the magnitude of said control signal and wherein a bias spring means is provided for biasing the head toward a direction opposite that in which the head is moved by the electromagnetic means in response to an increase in the magnitude of said control signal.
Claim 5
Dependent Claim
115 words
Apparatus as in claim 2 including a centrally pivoted horizontal lever having one arm connected to the head, a bias spring biasing said arm downwardly, means connecting the electromagnetic means plunger to the other arm of the lever, said electromagnetic means moving the plunger downwardly in response to an increase in the magnitude of said control signal and thereby moving the head upwardly toward said normal alignment position between the head and the track of recorded material on the tape, and said electromagnetic means allowing the bias spring to move the plunger upwardly and the head downwardly toward said normal vertical alignment position in response to a decrease in the magnitude of said control signal.
Claim 6
Dependent Claim
104 words
Apparatus as in claim 1 wherein said tape is an endless tape having thereon a plurality of horizontal tracks of magnetically recorded information connected with each other through inclined track portions, and wherein said head positioning means includes means responsive to a track switching control signal generated by the vertical position control head element as one of said inclined track portions is moved horizontally past the vertical position control head element to move the head from normal vertical alignment with a track preceding the inclined portion to normal vertical alignment with an adjacent track connected with the preceding track through said inclined track portion.
Claim 7
Dependent Claim
87 words
Apparatus as in claim 5 wherein said head positioning means comprises electromagnetic means having a plunger connected to move the head vertically, said electromagnetic means moving the plunger in response to variatIons in the magnitude of said control signal to urge the head toward said normal vertical alignment position and moving the plunger over a predetermined distance in response to said track switching control signal to move the head from the track preceding said track switching signal to the track connected therewith through said inclined track portion.
Claim 8
Dependent Claim
160 words
Apparatus as in claim 6 including a centrally pivoted horizontal lever having one arm connected for moving the head vertically and a bias spring for urging said arm downwardly, means connecting the plunger to the other arm of the lever, said electromagnetic means moving the plunger downwardly in response to an increase in the magnitude of said control signal and thereby moving the head upwardly toward said normal alignment position between the head and the track of recorded material on the tape, said electromagnetic means allowing the bias spring to move the head downwardly and the plunger upwardly in response to a decrease in the magnitude of said control signal, and said electromagnetic means moving the plunger downwardly over a predetermined distance in response to said track switching control signal to move the head from a normal alignment position with a track preceding the track switching control signal to normal alignment position with the next higher track on the tape.
Claim 9
Dependent Claim
53 words
Apparatus as in claim 7 wherein said electromagnetic means includes an actuating coil coaxial with the plunger and increasing in diameter downwardly to provide increasing magnetic flux as the plunger is moved downwardly against the force of the bias spring as the head is switched from lower to higher tracks on the tape.
Claim 10
Dependent Claim
42 words
Apparatus as in claim 7 for manually setting the plunger at defined positions with respect to the electromagnetic means to thereby set the magnetic head at defined positions with respect to the tape and to select a particular track of recorded material.
Claim 11
Dependent Claim
71 words
Apparatus as in claim 9 including a normally closed limit switch interposed between the vertical position control head element and the electromagnetic means, and means for setting the limit switch in a selected relationship with the plunger to cause opening the limit switch by the plunger when the plunger is in selected relationship to the electromagnetic means, thereby limiting selectively the upward movement of the head with respect to the tape.
Claim 12
Independent Claim
165 words
A method of maintaining a normal vertical alignment position between a magnetic head and a recording track of magnetically recorded information on a magnetic tape transported horizontally with respect to said magnetic head, comprising the steps of disposing a vertical position control head element at a defined vertical position with respect to the track when the magnetic head is in said normal vertical alignment position with respect to the track and deriving from said vertical position control head a control signal which varies as a function of the degree and sense of vertical displacement of the vertical position control head element from said defined vertical position thereof with respect to the track, said control signal being distinct and different from any signals provided by said magnetic head, and detecting defined variations in said control signal to move the magnetic head toward said normal vertical alignment position with respect to the track of magnetically recorded information as a function of said variation in the control signal.
Claim 13
Independent Claim
165 words
A method of maintaining a normal vertical alignment position between a magnetic head and a recording track of magnetically recorded information on a magnetic tape transported horizontally with respect to said magnetic head, comprising the steps of disposing a vertical position control head element at a defined vertical position with respect to the track when the magnetic head is in said normal vertical alignment position with respect to the track and deriving from said vertical position control head a control signal which varies as a function of the degree and sense of vertical displacement of the vertical position control head element from said defined vertical position thereof with respect to the track, said control signal being distinct and different from any signals provided by said magnetic head, and detecting defined variations in said control signal to move the magnetic head toward said normal vertical alignment position with respect to the track of magnetically recorded information as a function of said variation in the control signal.
Claim 14
Dependent Claim
42 words
Method as in claim 11 wherein the step of deriving the control signal includes magnetically reading by means of said vertical position control element the same track of magnetically recorded information with which the magnetic head is at said vertical alignment position.
Claim 15
Dependent Claim
124 words
Method as in claim 11 wherein the tape is an endless tape having thereon a plurality of horizontal tracks of magnetically recorded information connected with each other through inclined track portions, and including the step of deriving a track switching control signal by means of said vertical poSition control head element as one of said inclined track portions is moved horizontally past the vertical position control head element, and the step of moving the magnetic head from its normal vertical alignment position with a track preceding the inclined portion to a normal vertical alignment position with an adjacent track connected with the preceding track through said inclined track portion in response to a track switching control signal generated by said vertical position control head.
Claim 16
Dependent Claim
42 words
Method as in claim 13 wherein the step of deriving the control signal includes magnetically reading by means of said vertical position control element the same track of magnetically recorded information with which the magnetic head is at said vertical alignment position.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-10-29 | 1977-04-30 | 1977-10-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-29 | 1981-04-30 | 1981-10-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-29 | 1985-04-30 | 1985-10-30 | $7700.00 | Window Closed / Lapsed |