Patent US3571544A successfully refreshed from Google Patents.
US3571544A
Expired / Lapsed
US
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Magnetic key operated switch for electrically operated hand tools
Assignee: Individual
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Filing: 1968-10-21
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Granted: 1971-03-23
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Expires: 1988-10-21
Abstract
Abstract This invention relates to a switch for electrically operated hand tools, and the like, wherein the contact points of the switch are normally maintained yieldably separated, and one arm of said points is movable, and a ring is provided for the user of the device having a magnetized key, shaped to fit the particular key opening of the tool, so that when the key, mounted on a ring worn on a finger of the user, is inserted into the key opening, the movable arm will be moved into closed position, completing an electrical circuit through the motor of the tool, and upon removal of the key, for any reason, the tool will be immediately deactivated.
Inventors
- 👤 Hilary William Sheehan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 12:38
CPC Classifications
H; H01; H01H; H01H36/00; H01H36/0006; H01H36/0066; H01H9/00; H01H9/02; H01H9/06; H01H9/0214; H01H2009/0221; Y; Y10; Y10T; Y10T70/00; Y10T70/70; Y10T70/7441; Y10T70/778; Y10T70/7791; Y10T70/7904
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
103 words
In a switch for electrically operated hand tools, a switch housing, a spring mounted movable arm and a fixed arm, said arms being mounted in said housing and connected into an electrical circuit from a source of power through an electrically operated motor, contact points on said arms, a control arm on said movable arm formed of magnetic responsive metal, an opening in said housing adjacent said control arm and a magnetized key insertable into said opening to move said movable arm into contact with said fixed arm, the said key being mounted on a finger ring to be worn by the user.
Claim 2
Dependent Claim
103 words
In a switch for electrically operated hand tools, a switch housing, a spring mounted movable arm and a fixed arm, said arms being mounted in said housing and connected into an electrical circuit from a source of power through an electrically operated motor, contact points on said arms, a control arm on said movable arm formed of magnetic responsive metal, an opening in said housing adjacent said control arm and a magnetized key insertable into said opening to move said movable arm into contact with said fixed arm, the said key being mounted on a finger ring to be worn by the user.
Claim 3
Dependent Claim
29 words
The device defined in claim 1 wherein the key is mounted on a finger ring which may be adjusted to be mounted on the gloved finger of the user.
References Cited (Backward Citations)
US2735908A
Cited
US1174887A
Cited
US2625630A
Cited
US2767278A
Cited
DE1140952B
Cited
GB1138123A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-03-22 | 1974-09-21 | 1975-03-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-22 | 1978-09-21 | 1979-03-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-22 | 1982-09-21 | 1983-03-23 | $7700.00 | Window Closed / Lapsed |