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EP0090375A2 Expired / Lapsed EP ⏱️ 0.0 years remaining

Rotary magnetic head drum device

Assignee: Hitachi Ltd
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Filing: 1983-03-25
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Granted: —
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Expires: 2003-03-25
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Abstract

Abstract A rotary magnetic head drum device of a helical scan type including rotary magnetic heads (34a and 34b), and a head drum constituted by a rotary drum (3) and a stationary drum (2) located above and below the heads in juxtaposed relation and inclined at a predetermined angle of inclination 6 together with the heads. A tapering surface (371) or a stepped surface (372) is formed at the rotary drum located over the heads and extends from an end of a top surface of the rotary drum to an upper end (a) of an outer circumferential surface (D) thereof to reduce the thickness of an outer peripheral portion (37) of the rotary drum, to thereby reduce the vertical dimension (L) of the head drum when it is located in an inclined position.

Inventors

  • 👤 Shinji Okada
  • 👤 Masanori Kochi
  • 👤 Naoto Yoshida
  • 👤 Yasuji Moriyama

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-07 04:07
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/48; G11B5/52; G11B5/53; G11B15/00; G11B15/60; G11B15/61

Claims Analysis

Total Claims: 19
Claim 1
Independent Claim 158 words
A rotary magnetic head drum device comprising: a first drum and a second drum located in juxtaposed relation one above the other; and a head rotating member interposed between the first drum and the second drum and driven by an output shaft of a motor to rotate; said head drum device being located at a predetermined angle of inclination; wherein the improvement comprises: a reduced thickness portion formed at a top surface of the first drum located over the head rotating member to extend from an end of the top surface to an upper end of an outer circumferential surface of said first drum, said reduced thickness portion being provided to reduce the thickness of an outer peripheral portion of the first drum in a value commensurate with the angle of inclination of the head drum device, whereby the head drum device has its vertical dimension reduced when the head drum device is located in an inclined position.
Claim 2
Dependent Claim 158 words
A rotary magnetic head drum device comprising: a first drum and a second drum located in juxtaposed relation one above the other; and a head rotating member interposed between the first drum and the second drum and driven by an output shaft of a motor to rotate; said head drum device being located at a predetermined angle of inclination; wherein the improvement comprises: a reduced thickness portion formed at a top surface of the first drum located over the head rotating member to extend from an end of the top surface to an upper end of an outer circumferential surface of said first drum, said reduced thickness portion being provided to reduce the thickness of an outer peripheral portion of the first drum in a value commensurate with the angle of inclination of the head drum device, whereby the head drum device has its vertical dimension reduced when the head drum device is located in an inclined position.
Claim 3
Dependent Claim 35 words
A rotary magnetic head drum device as claimed in claim 1, wherein said reduced thickness portion comprises a tapering surface of an angle substantially equal to the angle of inclination of the head drum device.
Claim 4
Dependent Claim 41 words
A rotary magnetic head drum device as claimed in claim 1, wherein said reduced thickness portion comprises a stepped surface extending from the end of the top surface to the upper end of the outer circumferential surface of the first drum.
Claim 5
Dependent Claim 46 words
A rotary magnetic head drum device as claimed in claim 1, wherein said reduced thickness portion comprises a slope and a planar portion in combination extending from the end of the top surface to the upper end of the outer circumferential surface of the frist drum.
Claim 6
Dependent Claim 97 words
A rotary magnetic head drum device as claimed in claim 1, wherein said first drum comprises a rotary drum secured to the output shaft of the motor and having the head rotating member attached thereto to act as a unit therewith; said second drum comprises a stationary drum located in juxtaposed relation to a head supporting surface of said first drum; and said reduced thickness portion is formed at said rotary drum in a manner to extend from the end of the top surface to the upper end of the outer circumferential surface of the rotary drum.
Claim 7
Dependent Claim 90 words
A rotary magnetic head drum device as claimed in claim 1, wherein said first drum and said second drum are both stationary drums and said head rotating member is interposed between the two stationary drums and connected to the output shaft of the motor, and said reduced thickness portion is formed at one stationary drum located above the other stationary drum and extends from the end of the top surface to the upper end of the outer circumferential surface of the one stationary drum located above the other stationary drum.
Claim 8
Dependent Claim 170 words
A rotary magnetic head drum device comprising: a rotary drum secured to an output shaft of a motor and having a rotary magnetic head attached thereto; and a stationary drum located in juxtaposed relation to said rotary drum to constitute a head drum in association with said rotary drum; said head drum being located at a predetermined angle of inclination; wherein the improvement comprises: a reduced thickness portion formed at a top surface of one of the rotary drum and the stationary drum that is located above the other drum to extend from an end of the top surface to an upper end of an outer circumferential surface of the one drum located above the other drum, said reduced thickness portion being provided to reduce the thickness of an outer peripheral portion of the said one drum in a value commensurate with the angle of inclination of the head drum, whereby the overall height of the head drum is reduced when the head drum is located in an inclined position.
Claim 9
Dependent Claim 170 words
A rotary magnetic head drum device comprising: a rotary drum secured to an output shaft of a motor and having a rotary magnetic head attached thereto; and a stationary drum located in juxtaposed relation to said rotary drum to constitute a head drum in association with said rotary drum; said head drum being located at a predetermined angle of inclination; wherein the improvement comprises: a reduced thickness portion formed at a top surface of one of the rotary drum and the stationary drum that is located above the other drum to extend from an end of the top surface to an upper end of an outer circumferential surface of the one drum located above the other drum, said reduced thickness portion being provided to reduce the thickness of an outer peripheral portion of the said one drum in a value commensurate with the angle of inclination of the head drum, whereby the overall height of the head drum is reduced when the head drum is located in an inclined position.
Claim 10
Dependent Claim 34 words
A rotary magnetic head drum device as claimed in claim 7, wherein said reduced thickness portion comprises a tapering surface of an angle substantially equal to the angle of inclination of the head drum.
Claim 11
Dependent Claim 46 words
A rotary magnetic head drum device as claimed in claim 7, wherein said reduced thickness portion comprises a stepped surface extending from the end of the top surface to the upper end of the outer circumferential surface of the rotary drum located above the stationary drum.
Claim 12
Dependent Claim 207 words
A rotary magnetic head drum device comprising: a rotary drum secured to an output shaft of a motor and having a rotary magnetic head attached to its bottom surface; and a stationary drum located below the rotary drum in juxtaposed relation to constitute a head drum in association with said rotary drum; said head drum being located at an angle of inclination which is in the range between an angle substnantially equal to a lead angle of a tape edge guide portion formed on the stationary drum and an angle substantially twice the lead angle; and a reduced thickness portion formed at an outer peripheral portion of a top surface of the rotary drum opposite the bottom surface supporting the rotary magnetic head and extendig from an end of the top surface to an upper end of an outer circumferential surface of the rotary drum, whereby the overall height of the head drum is reduced and the axial dimension of the outer circumferential surface of the rotary drum is set at a minimum value which may vary depending on the width of a tape brought into contact with the rotary drum and a magnetic recoding pattern thereof when the head drum is located in an inclined position.
Claim 13
Dependent Claim 207 words
A rotary magnetic head drum device comprising: a rotary drum secured to an output shaft of a motor and having a rotary magnetic head attached to its bottom surface; and a stationary drum located below the rotary drum in juxtaposed relation to constitute a head drum in association with said rotary drum; said head drum being located at an angle of inclination which is in the range between an angle substnantially equal to a lead angle of a tape edge guide portion formed on the stationary drum and an angle substantially twice the lead angle; and a reduced thickness portion formed at an outer peripheral portion of a top surface of the rotary drum opposite the bottom surface supporting the rotary magnetic head and extendig from an end of the top surface to an upper end of an outer circumferential surface of the rotary drum, whereby the overall height of the head drum is reduced and the axial dimension of the outer circumferential surface of the rotary drum is set at a minimum value which may vary depending on the width of a tape brought into contact with the rotary drum and a magnetic recoding pattern thereof when the head drum is located in an inclined position.
Claim 14
Dependent Claim 57 words
A rotary magnetic head drum device as claimed in claim 10, wherein said reduced thickness portion comprises a tapering surface extending from the end of the top surface of the rotary drum to the upper end of the outer circumferential surface thereof and having substantially the same angle as the angle of inclination of the head drum.
Claim 15
Dependent Claim 42 words
A rotary magnetic head drum device as claimed in claim 10, wherein said reduced thickness portion comprises a stepped surface extending from the end of the top surface of the rotary drum to the upper end of the outer circumferential surface thereof.
Claim 16
Dependent Claim 134 words
A rotary magnetic head drum device of a helical scan type comprising: a rotary magnetic head; and an upper and a lower drums located above and below said magnetic head respectively in juxtaposed relation to constitute a head drum, said upper and lower drums being located together with the magnetic head in a position inclined a predetermined angle of inclination; wherein the improvement comprises: a reduced thickness portion formed at the upper drum located over the rotary magnetic head and extending from an end of a top surface to an upper end of an outer circumferential surface of the upper drum to reduced the thickness of an outer peripheral portion of the upper drum, whereby the vertical dimension of the head drum is reduced when the head drum is located in an inclined position.
Claim 17
Dependent Claim 134 words
A rotary magnetic head drum device of a helical scan type comprising: a rotary magnetic head; and an upper and a lower drums located above and below said magnetic head respectively in juxtaposed relation to constitute a head drum, said upper and lower drums being located together with the magnetic head in a position inclined a predetermined angle of inclination; wherein the improvement comprises: a reduced thickness portion formed at the upper drum located over the rotary magnetic head and extending from an end of a top surface to an upper end of an outer circumferential surface of the upper drum to reduced the thickness of an outer peripheral portion of the upper drum, whereby the vertical dimension of the head drum is reduced when the head drum is located in an inclined position.
Claim 18
Dependent Claim 56 words
A rotary magnetic head drum device as claimed in claim 13, wherein said reduced thickness portion comprises a tapering surface extending from the end of the top surface to the upper end of the outer circumferential surface of the upper drum and having substantially the same angle as the angle of inclination of the head drum.
Claim 19
Dependent Claim 41 words
A rotary magnetic head drum device as claimed in claim 13, wherein said reduced thickness portion comprises a stepped surface extending from the end of the top surface to the upper end of the outer circumferential surface of the upper drum.

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