US4034413A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic head lifting device
Assignee: Motorola Solutions Inc
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Filing: 1975-08-29
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Granted: 1977-07-05
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Expires: 1995-08-29
Abstract
Abstract A magnetic head lifting device for a tape recorder is disclosed in which the turning force of a capstan shaft is used as a drive source for the head lifting device. The device includes a rotary body having indented portions in a peripheral edge, a ring attached to a capstan shaft and engageable with the nonindented portions of the peripheral edge of the rotary body, a rotary body urging member, a rotary body stopping member, an electromagnet, an antiexcessive rotation member positioned by the electromagnet to positively prevent excessive rotation of the rotary body, and a stepped surface cam associated with said rotary body for lifting the magnetic head in response to the rotation of the rotary body. The head lifting device provides a positive engagement and disengagement between the capstan shaft and the rotary body and prevents any malfunction due to an excessive rotation of the rotary body by the capstan shaft. The device is miniaturized since only a small capacity electromagnet is required.
Inventors
- 👤 Kumeo Tahara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 09:06
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/48; G11B5/54; G11B5/55; G11B5/5504
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
194 words
A magnetic head lifting device adaptable for use in a multi-track tape player, comprising: a rotary body having a peripheral edge with indented portions therein; ring means rotatable in association with a capstan shaft and positioned for rotating said rotary body by engaging the peripheral edge of said rotary body and disengaging said edge at said indented portions thereof, urge member means for selectively urging said rotary body in a predetermined direction of rotation; stopper means for selectively engaging said rotary body and preventing the rotation of said rotary body by said urge member means; actuation means for disengaging said stopper means from said rotary body and permitting the rotation of said rotary body by said urge means, the rotation of said rotary body thereby causing said ring means to engage the peripheral edge of said rotary body; anti-excessive rotation means including a member having its position controlled by said actuation means for selectively engaging said rotary body and positively preventing an excessive rotation of said rotary body by said ring means, and stepped surface cam means integrally associated with the rotation of said rotary body for moving the position of the magnetic head.
Claim 2
Dependent Claim
194 words
A magnetic head lifting device adaptable for use in a multi-track tape player, comprising: a rotary body having a peripheral edge with indented portions therein; ring means rotatable in association with a capstan shaft and positioned for rotating said rotary body by engaging the peripheral edge of said rotary body and disengaging said edge at said indented portions thereof, urge member means for selectively urging said rotary body in a predetermined direction of rotation; stopper means for selectively engaging said rotary body and preventing the rotation of said rotary body by said urge member means; actuation means for disengaging said stopper means from said rotary body and permitting the rotation of said rotary body by said urge means, the rotation of said rotary body thereby causing said ring means to engage the peripheral edge of said rotary body; anti-excessive rotation means including a member having its position controlled by said actuation means for selectively engaging said rotary body and positively preventing an excessive rotation of said rotary body by said ring means, and stepped surface cam means integrally associated with the rotation of said rotary body for moving the position of the magnetic head.
Claim 3
Dependent Claim
27 words
A magnetic head lifting device according to claim 1 wherein said ring means is concentrically attached to the capstan shaft and is composed of an elastic material.
Claim 4
Dependent Claim
20 words
A magnetic head lifting device according to claim 1 wherein said anti-excessive rotation member is pivotable about a first axis.
Claim 5
Dependent Claim
21 words
A magnetic head lifting device according to claim 3 wherein said stopper means includes a member pivotable about said first axis.
Claim 6
Dependent Claim
24 words
A magnetic head lifting device according to claim 4 wherein said stopper member and said anti-excessive rotation member are rigidly attached to each other.
Claim 7
Dependent Claim
35 words
A magnetic head lifting device according to claim 5 wherein said anti-excessive rotation member and said stopper member are positioned to form an angle which includes the axis about which said rotary body is rotated.
Claim 8
Dependent Claim
23 words
A magnetic head lifting device according to claim 5 wherein said urge means includes a member which is pivotable about said first axis.
Claim 9
Dependent Claim
25 words
A magnetic head lifting device according to claim 5 wherein said rotary body has pins rigidly attached thereto for selectively engaging said anti-excessive rotation member.
Claim 10
Dependent Claim
25 words
A magnetic head lifting device according to claim 5 wherein said rotary body has engaging members rigidly attached thereto for selectively engaging said stopper member.
Claim 11
Dependent Claim
16 words
A magnetic head lifting device according to claim 5 wherein said actuating means includes an electromagnet.
References Cited (Backward Citations)
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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) | 1980-07-04 | 1981-01-03 | 1981-07-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-07-04 | 1985-01-03 | 1985-07-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-07-04 | 1989-01-03 | 1989-07-05 | $7700.00 | Window Closed / Lapsed |