US5257255A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recording and/or reproducing apparatus with sensor for detecting head speed or acceleration
Assignee: Canon Electronics Inc
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Filing: 1992-07-31
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Granted: 1993-10-26
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Expires: 2012-07-31
Abstract
Abstract A head for writing data into and/or reading data out of a recording medium such as a magnetic disc is displaced along a path by a motor such as a voice coil motor. The moving member of the motor is disposed on one side of the path, and another moving member of a speed sensor for detecting the head displacement speed is disposed on the opposite side. As a result, an unbalanced mass arrangement with respect to the path along which the head is displaced will not occur. The signal from the speed sensor can be used, for example, to interrupt a write operation if a mechanical impact occurs. Furthermore, even in an embodiment in which a coil is wound around the moving member of the speed sensor so that the head displacement speed is detected as a voltage induced across the coil as the head is displaced, the motor and the speed sensor are disposed in spaced-apart-relationship with each other and the speed sensor is less susceptible to adverse effects caused by the leakage flux from the motor.
Inventors
- 👤 Masao Morimoto
- 👤 Hitoshi Kurihara
- 👤 Ryuichi Negishi
- 👤 Toru Okada
- 👤 Masae Ikeda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 01:15
CPC Classifications
G; G11; G11B; G11B33/00; G11B33/02; G11B33/08; G11B19/00; G11B19/02; G11B5/00; G11B5/48; G11B5/54; G11B5/55; G11B5/5521; G11B5/5582
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
170 words
A recording and/or reproducing apparatus, comprising: a head means for writing data into and/or reading data out of a recording medium; a displacing means for displacing said head means along a path to a write or read region on said recording medium, said displacing means including a motor having a first moving member that is disposed on one side of said path, and joining means for joining said head means to said first moving member; a speed sensor means for detecting the displacement speed of said head means, said speed sensor means including a second moving member that is disposed on the other side of said path, said second moving member being coupled to said displacing means; and control means for permitting or inhibiting a write operation by said head means in response to the displacement speed of said head means detected by said speed sensor means, said control means inhibiting the write operation by the head means if the displacement speed of said head means exceeds a predetermined value.
Claim 2
Dependent Claim
170 words
A recording and/or reproducing apparatus, comprising: a head means for writing data into and/or reading data out of a recording medium; a displacing means for displacing said head means along a path to a write or read region on said recording medium, said displacing means including a motor having a first moving member that is disposed on one side of said path, and joining means for joining said head means to said first moving member; a speed sensor means for detecting the displacement speed of said head means, said speed sensor means including a second moving member that is disposed on the other side of said path, said second moving member being coupled to said displacing means; and control means for permitting or inhibiting a write operation by said head means in response to the displacement speed of said head means detected by said speed sensor means, said control means inhibiting the write operation by the head means if the displacement speed of said head means exceeds a predetermined value.
Claim 3
Dependent Claim
53 words
A recording and/or reproducing apparatus as claimed in claim 1, wherein said motor is a linear voice coil motor; and wherein said speed sensor means has a coil wound around said second moving member, a yoke extending through said coil and securely attached to said apparatus, and a magnet combined with said yoke.
Claim 4
Dependent Claim
61 words
A recording and/or reproducing apparatus as claimed in claim 1, wherein said recording medium is in the form of a disc having surfaces on which are defined a plurality of write or read regions; and wherein said head means is moved toward or away from the center of said disc when it is displaced along said path by said displacing means.
Claim 5
Dependent Claim
26 words
A recording and/or reproducing apparatus as claimed in claim 3, wherein said disc is a magnetic disc; and wherein said head means is a magnetic head.
Claim 6
Dependent Claim
64 words
A recording and/or reproducing apparatus as in claim 1, wherein said speed sensor means generates a speed signal, and wherein said control means comprises a differentiating circuit means for differentiating the speed signal from said speed sensor means to provide a differentiated signal, said write operation being inhibited when said differentiated signal from said differentiating circuit means is in excess of a predetermined level.
Claim 7
Dependent Claim
48 words
A recording and/or reproducing apparatus as claimed in claim 1, wherein said joining means comprises a head carriage on which said head means is mounted, and means for connecting said first moving means to said head carriage, said second moving member additionally being connected to said head carriage.
Claim 8
Dependent Claim
159 words
A recording and/or reproducing apparatus, comprising: a head means for writing data into and/or reading data out of a recording medium; a head displacement means for displacing said head means to a write or read region on said recording medium; a speed sensor means for detecting the displacement speed of said head means, said speed sensor means including a coil assembly having a first coil movable in unison with said head means and a second coil which is maintained stationary relative to said head means and which is wound in a direction opposite to the direction of winding of said first coil, a voltage being induced across said coil assembly in accordance with the displacement speed of said head means when said head means is displaced; and control means for controlling said head means so as to inhibit a write operation by said head means if the displacement speed detected by said speed sensor means exceeds a predetermined value.
Claim 9
Dependent Claim
159 words
A recording and/or reproducing apparatus, comprising: a head means for writing data into and/or reading data out of a recording medium; a head displacement means for displacing said head means to a write or read region on said recording medium; a speed sensor means for detecting the displacement speed of said head means, said speed sensor means including a coil assembly having a first coil movable in unison with said head means and a second coil which is maintained stationary relative to said head means and which is wound in a direction opposite to the direction of winding of said first coil, a voltage being induced across said coil assembly in accordance with the displacement speed of said head means when said head means is displaced; and control means for controlling said head means so as to inhibit a write operation by said head means if the displacement speed detected by said speed sensor means exceeds a predetermined value.
Claim 10
Dependent Claim
44 words
A recording and/or reproducing apparatus as claimed in claim 7, wherein said head displacement means comprises a head carriage on which said head means is mounted, and a linear voice coil motor equipped with a moving member that is joined to said head carriage.
Claim 11
Dependent Claim
65 words
A recording and/or reproducing apparatus as claimed in claim 8, wherein said head displacement means displaces said head means along a path; wherein said moving member is disposed on one side of said path; and wherein said speed sensor means further comprises another moving member that is disposed on the other side of said path, said first coil being wound around said another moving member.
Claim 12
Dependent Claim
162 words
A recording and/or reproducing apparatus, comprising: a head means for writing data into and/or reading data out of a recording medium; a head displacement means for displacing said head means along a path to a write or read region on said recording medium; and a speed sensor means for detecting the displacement speed of said head means, said speed sensor means including a first yoke in the shape of a hollow cylinder disposed parallel to said path, a magnet lining on the inner surface of said first yoke, a second yoke in the shape of a rod disposed coaxially in said first yoke, and a moving member which is joined to said head displacement means through a slit cut through said first yoke and said magnetic lining, said slit being parallel to said path so as to permit said moving member to be movable in unison with said head means along said second yoke, and a coil wound around said moving member.
Claim 13
Dependent Claim
162 words
A recording and/or reproducing apparatus, comprising: a head means for writing data into and/or reading data out of a recording medium; a head displacement means for displacing said head means along a path to a write or read region on said recording medium; and a speed sensor means for detecting the displacement speed of said head means, said speed sensor means including a first yoke in the shape of a hollow cylinder disposed parallel to said path, a magnet lining on the inner surface of said first yoke, a second yoke in the shape of a rod disposed coaxially in said first yoke, and a moving member which is joined to said head displacement means through a slit cut through said first yoke and said magnetic lining, said slit being parallel to said path so as to permit said moving member to be movable in unison with said head means along said second yoke, and a coil wound around said moving member.
Claim 14
Dependent Claim
44 words
A recording and/or reproducing apparatus as claimed in claim 10, wherein said head displacement means comprises a head carriage on which said head means is mounted, and a linear voice coil motor which has a moving member that is connected to said head carriage.
Claim 15
Dependent Claim
38 words
A recording and/or reproducing apparatus as claimed in claim 11, wherein said moving member of said linear voice coil motor and said movable member of said speed sensor means are arranged at the opposite sides of said path.
Claim 16
Dependent Claim
129 words
A recording and/or reproducing apparatus, comprising: a head means for writing data into and/or reading data out of a recording medium; a head displacement means for displacing said head means to a write or read region on said recording medium; an acceleration data generating means for generating an output signal representing the acceleration of said head means relative to said recording medium, said acceleration data generating means being connected directly to said head displacement means to detect movement of said head displacement means; and a control means for permitting or inhibiting a write operation by said head means in response to the output signal of said acceleration data generating means, said control means inhibiting the write operation by said head means if the output signal exceeds a predetermined value.
Claim 17
Dependent Claim
129 words
A recording and/or reproducing apparatus, comprising: a head means for writing data into and/or reading data out of a recording medium; a head displacement means for displacing said head means to a write or read region on said recording medium; an acceleration data generating means for generating an output signal representing the acceleration of said head means relative to said recording medium, said acceleration data generating means being connected directly to said head displacement means to detect movement of said head displacement means; and a control means for permitting or inhibiting a write operation by said head means in response to the output signal of said acceleration data generating means, said control means inhibiting the write operation by said head means if the output signal exceeds a predetermined value.
Claim 18
Dependent Claim
89 words
A recording and/or reproducing apparatus as claimed in claim 13, wherein said acceleration data generating means comprises a speed sensor means for detecting the relative speed of said head means with respect to said recording medium to provide a speed signal, and a differentiating circuit means for differentiating the speed signal to thereby provide said output signal of said acceleration data generating means, the write operation by said head means being inhibited when the output signal from said acceleration data generating means is in excess of the predetermined value.
Claim 19
Dependent Claim
71 words
A recording and/or reproducing apparatus as claimed in claim 13, wherein said acceleration data generating means comprises an acceleration sensor means for detecting the acceleration of said head means relative to said recording medium and providing said output signal of said acceleration data generating means, the write operation by said head means being inhibited when the output signal from said acceleration data generating means is in excess of the predetermined value.
Claim 20
Dependent Claim
131 words
A recording and/or reproducing apparatus, comprising: a head means for writing data into and/or reading data out of a recording medium; a head displacement means for displacing said head means relative to said recording medium so as to position said head means on a write or read region of said recording medium; an acceleration data generating means for generating an output signal representing the relative acceleration of said head means with respect to said recording medium, said acceleration data generating means being connected directly to said head displacement means to detect movement of said head displacement means; and a control means for causing said head displacement means to displace said head means by a distance related to the acceleration in response to the output signal of said acceleration data generating means.
Claim 21
Dependent Claim
131 words
A recording and/or reproducing apparatus, comprising: a head means for writing data into and/or reading data out of a recording medium; a head displacement means for displacing said head means relative to said recording medium so as to position said head means on a write or read region of said recording medium; an acceleration data generating means for generating an output signal representing the relative acceleration of said head means with respect to said recording medium, said acceleration data generating means being connected directly to said head displacement means to detect movement of said head displacement means; and a control means for causing said head displacement means to displace said head means by a distance related to the acceleration in response to the output signal of said acceleration data generating means.
Claim 22
Dependent Claim
51 words
A recording and/or reproducing apparatus as claimed in claim 16, wherein said head displacement means includes a motor; wherein said acceleration data generating means comprises an acceleration sensor which provides said output signal; and wherein said control means comprises means for adding said output signal to data for energizing said motor.
Claim 23
Dependent Claim
18 words
A recording and/or reproducing apparatus as claimed in claim 17, wherein said means for adding comprises an adder.
Claim 24
Dependent Claim
182 words
A disc drive apparatus, comprising: a head means for writing data into and/or reading data out of a disc; a head displacement means for displacing said head means in a radial direction of said disc to write or read region on said disc; an acceleration data generating means for generating an output signal representing the acceleration of said head means in said radial direction, said acceleration data generating means being connected directly to said head displacement means to detect acceleration of said head displacement means, said acceleration data generating means including a speed sensor means for detecting the relative speed of said head means with respect to said disc to provide a speed signal, and a differentiating circuit means for differentiating the speed signal to thereby provide said output signal of said acceleration data generating means; and a control means for permitting or inhibiting a write operation by said head means in response to the output signal of said acceleration data generating means, said control means inhibiting the write operation by said head means if the output signal exceeds a predetermined value.
Claim 25
Dependent Claim
182 words
A disc drive apparatus, comprising: a head means for writing data into and/or reading data out of a disc; a head displacement means for displacing said head means in a radial direction of said disc to write or read region on said disc; an acceleration data generating means for generating an output signal representing the acceleration of said head means in said radial direction, said acceleration data generating means being connected directly to said head displacement means to detect acceleration of said head displacement means, said acceleration data generating means including a speed sensor means for detecting the relative speed of said head means with respect to said disc to provide a speed signal, and a differentiating circuit means for differentiating the speed signal to thereby provide said output signal of said acceleration data generating means; and a control means for permitting or inhibiting a write operation by said head means in response to the output signal of said acceleration data generating means, said control means inhibiting the write operation by said head means if the output signal exceeds a predetermined value.
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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) | 1996-10-25 | 1997-04-26 | 1997-10-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-10-25 | 2001-04-26 | 2001-10-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-10-25 | 2005-04-26 | 2005-10-26 | $7700.00 | Window Closed / Lapsed |