US3665388A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tire air pressure detection and signalling device
Assignee: Eltico Manufacturing Ltd
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Filing: 1969-08-12
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Granted: 1972-05-23
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Expires: 1989-08-12
Abstract
Abstract An apparatus for detecting dangerous deflation of automobile tires and for signaling the existence of the deflation. A sensor in the form of an inductance device is positioned at a fixed distance from the axis of rotation of the wheel. A metallic annulus is carried within the tire casing and is moved away from the sensor to change the reactance of the inductance when the tire is dangerously deflected. The change of inductance is used to operate a relay for operating a signaling device.
Inventors
- 👤 Erich Cornelius Johnsen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 21:31
CPC Classifications
B; B60; B60C; B60C23/00; B60C23/02; B60C23/04; B60C23/0408; B60C23/0422; B60C23/0433; B60C23/0435; B60C23/0444
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
92 words
A tire deflation detection apparatus comprising an inductor device, means carried by the tire for changing the reactance of said inductor device upon a preselected deflation of the tire, and means responsive to the change of reactance for indicating said change, the means for changing the reactance comprising an annulus of metal elements and means responsive to the pressure in the tire for changing the diameter of the annulus so that the annulus is alternatively within and without the flux field of the device dependent on the occurrence of said preselected deflation.
Claim 2
Dependent Claim
92 words
A tire deflation detection apparatus comprising an inductor device, means carried by the tire for changing the reactance of said inductor device upon a preselected deflation of the tire, and means responsive to the change of reactance for indicating said change, the means for changing the reactance comprising an annulus of metal elements and means responsive to the pressure in the tire for changing the diameter of the annulus so that the annulus is alternatively within and without the flux field of the device dependent on the occurrence of said preselected deflation.
Claim 3
Dependent Claim
23 words
An apparatus as defined in claim 1, wherein the annulus of metal elements are arcuate segments embedded in an annulus of elastomeric material.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-23 | 1975-11-22 | 1976-05-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-23 | 1979-11-22 | 1980-05-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-23 | 1983-11-22 | 1984-05-23 | $7700.00 | Window Closed / Lapsed |