US3873787A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Air-pressure switch device for pneumatic tires
Assignee: Honda Motor Co Ltd
•
Filing: 1973-12-26
•
Granted: 1975-03-25
•
Expires: 1993-12-26
Abstract
Abstract An alarm device capable of detecting reduction in vehicular tire air pressure below a critical level irrespective of the vehicle speed, notwithstanding that the critical pressure level is variable with the vehicle speed. It includes detector means, a signalling circuit including a magnetic switch, a magnet secured to a casing of the detector means, and a spring-biased, airpressure responsive magnetic short circuiting member which is preferably in a floating state in the casing free from friction, for accurate detection of the variation in the air pressure within the tire.
Inventors
- 👤 Akio Nozi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 12:08
CPC Classifications
B; B60; B60C; B60C23/00; B60C23/02; B60C23/04; B60C23/0408; B60C23/0422; B60C23/0425
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
171 words
An air-pressure alarm device for pneumatic tires, comprising pressure detector means (5) secured to portion (3) of a vehicle wheel (1) for detecting air pressure in the pneumatic tire of the wheel, and an alarm signalling circuit (8) including a magnetically operable switch (7) secured to a stationary component (6) of the vehicle in a position opposite to said detector means, the latter including a casing (9) fixed to the wheel portion, a magnet (11) secured to said casing, spring means (15) arranged in said casing, and a magnetic short-circuiting member (12) accommodated in said casing for movement in a direction toward said magnet under the effect of the air pressure in the tire, and movable in the opposite direction, away from said magnet, under the combined effect of the bias of said spring means and the centrifugal force acting upon said magnetic member upon rotation of the wheel, said magnet being operable to close said switch to complete said signalling circuit upon separation of said magnetic member from said magnet.
Claim 2
Dependent Claim
171 words
An air-pressure alarm device for pneumatic tires, comprising pressure detector means (5) secured to portion (3) of a vehicle wheel (1) for detecting air pressure in the pneumatic tire of the wheel, and an alarm signalling circuit (8) including a magnetically operable switch (7) secured to a stationary component (6) of the vehicle in a position opposite to said detector means, the latter including a casing (9) fixed to the wheel portion, a magnet (11) secured to said casing, spring means (15) arranged in said casing, and a magnetic short-circuiting member (12) accommodated in said casing for movement in a direction toward said magnet under the effect of the air pressure in the tire, and movable in the opposite direction, away from said magnet, under the combined effect of the bias of said spring means and the centrifugal force acting upon said magnetic member upon rotation of the wheel, said magnet being operable to close said switch to complete said signalling circuit upon separation of said magnetic member from said magnet.
Claim 3
Dependent Claim
117 words
The alarm device as defined in claim 1, wherein said magnet (11) is in fixed relation to said casing (9), said magnetic member (12) is afloat in said casing in a position opposite to said magnet, said spring means (15) is arranged to normally bias said magnetic member in a direction away from said magnet, and wherein said detector means (5) further includes an air-pressure responsive displacement member (14) arranged in said casing substantially transversely thereof, for movement in response to variations in the air pressure in the tire, said magnetic member being connected at one end with said displacement member and supported at the other end by said spring means for movement under the guidance thereof.
References Cited (Backward Citations)
US1683343A
Cited
US2629086A
Cited
US3521230A
Cited
US3638180A
Cited
US3654601A
Cited
US3611220A
Cited
US3781787A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-03-24 | 1978-09-23 | 1979-03-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-24 | 1982-09-23 | 1983-03-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-24 | 1986-09-23 | 1987-03-25 | $7700.00 | Window Closed / Lapsed |