US3781787A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tire pressure detecting apparatus
Assignee: Individual
•
Filing: 1972-06-13
•
Granted: 1973-12-25
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Expires: 1992-06-13
Abstract
Abstract The detecting apparatus includes a rotatable bar-type permanent magnet mechanically independent of, but operatively associated with, a magnet position sensing member such as a reed switch or a coil wound on a magnetic core. When the magnet has one predetermined position, the position sensing device gates a thyristor to trigger an alarm which may be an audio alarm, a visual alarm, or both. The magnet is secured to the outer end of a shaft mounted in a casing which, in turn, is mounted through a wheel rim, and the inner portion of the shaft has a latching configuration. An externally accessible flexible shaft may be manually pressed to swing the magnet to a position in which it does not operate the magnetic sensing device and, in this position, the latching means on the shaft is engaged by one end of a spring biased rod. The other end of the spring biased rod is associated with a diaphragm subjected to the pressure of the air within the tire and the wheel rim so that, when the air pressure drops, the spring biased rod is retracted to release the shaft. A spring then rotates the shaft to swing the magnet into a position in which it is operative on the reed switch or the winding wound on the magnetic core. The flexible shaft for setting the magnet to the latching position may be operated by air pressure responsive to inflation of the tire.
Inventors
- 👤 U Sugiyama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 20:20
CPC Classifications
B; B60; B60C; B60C23/00; B60C23/02; B60C23/04; B60C23/0408; B60C23/0422; B60C23/0425
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
236 words
Tire pressure detecting apparatus comprising, in combination, a housing arranged for mounting in a tire and wheel rim assembly with its inner end positioned in the interior of the assembly and its outer end positioned externally of the assembly; a shaft rotatably mounted in said housing and having a latch portion adjacent its inner end; a permanent bar magnet secured to said shaft adjacent the outer end of said housing to extend diametrically of said shaft; a magnetically actuated detecting means, forming part of an alarm unit, positioned adjacent the outer end of said housing and mechanically separate therefrom, said detecting means having a preset orientation such that it is magnetically activated by said bar magnet when said bar magnet has an alarm operating position; spring means operatively engaged between said housing and said shaft and biasing said magnet to its operating position; a resetting means extending into said housing and operable to engage said magnet and rotate it from its operating position to a reset in which said magnet is ineffective to activate said detecting means; and tire air pressure responsive means mounted on the inner end of said housing and including latch means engageable with said shaft latch portion when said magnet is rotated to its reset position; said latch means disengaging said latch portion responsive to a decrease in tire air pressure, for spring biased rotation of said magnet to its operating position.
Claim 2
Dependent Claim
236 words
Tire pressure detecting apparatus comprising, in combination, a housing arranged for mounting in a tire and wheel rim assembly with its inner end positioned in the interior of the assembly and its outer end positioned externally of the assembly; a shaft rotatably mounted in said housing and having a latch portion adjacent its inner end; a permanent bar magnet secured to said shaft adjacent the outer end of said housing to extend diametrically of said shaft; a magnetically actuated detecting means, forming part of an alarm unit, positioned adjacent the outer end of said housing and mechanically separate therefrom, said detecting means having a preset orientation such that it is magnetically activated by said bar magnet when said bar magnet has an alarm operating position; spring means operatively engaged between said housing and said shaft and biasing said magnet to its operating position; a resetting means extending into said housing and operable to engage said magnet and rotate it from its operating position to a reset in which said magnet is ineffective to activate said detecting means; and tire air pressure responsive means mounted on the inner end of said housing and including latch means engageable with said shaft latch portion when said magnet is rotated to its reset position; said latch means disengaging said latch portion responsive to a decrease in tire air pressure, for spring biased rotation of said magnet to its operating position.
Claim 3
Dependent Claim
28 words
Tire pressure detecting apparatus, as claimed in claim 1, including means biasing said resetting means to a position in which said resetting means is disengaged from said magnet.
Claim 4
Dependent Claim
22 words
Tire pressure detecting apparatus, as claimed in claim 1, in which said resetting means includes an externally accessible manually operated operating member.
Claim 5
Dependent Claim
47 words
Tire pressure detecting apparatus, as claimed in claim 1, including inflation air operable means connected to the tire valve and to said resetting means; said inflation air operated means actuating said resetting means to rotate said magnet to its reset position responsive to inflation of the tire.
Claim 6
Dependent Claim
18 words
Tire pressure detecting apparatus, as claimed in claim 1, in which said detecting means is a reed switch.
Claim 7
Dependent Claim
25 words
Tire pressure detecting apparatus, as claimed in claim 1, in which said detecting means is a coil wound on an armature having an air gap.
Claim 8
Dependent Claim
98 words
Tire pressure detecting apparatus, as claimed in claim 1, in which said tire air pressure responsive means comprises a cylindrical casing secured to the inner end of said housing and opening into the latter; said latch means comprising an operating lever reciprocable in said casing and having an inner end engageable with said shaft latch portion; a diaphragm closing the outer end of said casing and subjected, on one side, to the tire air pressure; and spring means biasing said lever to engage said diaphragm and to a position disengaging its inner end from said shaft latch portion.
Claim 9
Dependent Claim
67 words
Tire pressure detecting apparatus, as claimed in claim 1, in which the outer end of said housing defines a cylindrical chamber in which said permanent bar magnet is rotatable; said resetting means comprising a flexible shaft extending tangentially into said chamber to engage said bar magnet; and means biasing said flexible shaft to a retracted position in which its inner end is disengaged from said bar magnet.
Claim 10
Dependent Claim
22 words
Tire pressure detecting apparatus, as claimed in claim 8, including a manual operating handle on the outer end of said flexible shaft.
Claim 11
Dependent Claim
80 words
Tire pressure detecting apparatus, as claimed in claim 8, including a cylinder having one end connected to and communicating with the tire inflating valve; said flexible shaft extending into the opposite end of said cylinder; and a piston secured to said flexible shaft and reciprocable in said cylinder; whereby, upon inflation of the tire, said piston is moved in a direction to project said flexible shaft to engage said bar magnet to rotate said bar magnet to its reset position.
References Cited (Backward Citations)
US2057556A
Cited
US3715719A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-12-24 | 1977-06-25 | 1977-12-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-24 | 1981-06-25 | 1981-12-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-24 | 1985-06-25 | 1985-12-25 | $7700.00 | Window Closed / Lapsed |