US5900808A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low pressure warning system
Assignee: Individual
•
Filing: 1997-02-21
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Granted: 1999-05-04
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Expires: 2017-02-21
Abstract
Abstract A Low Pressure Warning Device, System and Method is disclosed. The disclosed system is compact, and low cost but has an extremely long term service life. Further disclosed is sensing means that actively monitors the pressure conditions of a pneumatic chamber without drawing electrical power. The disclosed preferred sensing means will further detects various conditions, including activation-, normal- and low-pressure conditions. Also disclosed is a device that is installable within the pneumatic tire of a vehicle such that it is theft- and tamper-resistant. The disclosed device is resistant to truck tire operating temperatures and is further provided with a protective casing to prevent damage or contamination of the system components. Still further disclosed are a transmitter and receiver that are configured to transmit and receive encoded signals to permit great flexibility in vehicle monitoring combinations, while also providing the localization of the pneumatic chamber experiencing a low pressure condition. The disclosed transmitter provides alarm signal transmissions that are pulsed to shorten transmission duration and consequently reduce transmitter power consumption as well as improve receiver reliability. Also disclosed is a transmitter-sensor that includes battery prolonging means to retard passivation layer buildup within the battery.
Inventors
- 👤 Michael E. Lebo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 16:15
CPC Classifications
B; B60; B60C; B60C23/00; B60C23/02; B60C23/04; B60C23/0408; B60C23/005; B60C23/007; B60C23/009; B60C23/0422; B60C23/0433
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
127 words
A device for sensing a condition of a pneumatic chamber, comprising: a base; sensing means, associated with said base, for monitoring the chamber condition and detecting a normal condition an abnormal condition, and an inactive condition; alarm circuit means, associated with said base, for generating signals indicative of the chamber condition, including: switching means operatively connected to said alarm circuit means and responsive to said sensing means for de-energizing said alarm circuit means when said sensing means detects a normal condition and energizing said alarm circuit means when said sensing means detects an abnormal condition; and power supply means operatively connected to power said switching means and said alarm circuit means, said operative connection of said power supply means being disconnectable when said inactive condition is detected.
Claim 2
Independent Claim
127 words
A device for sensing a condition of a pneumatic chamber, comprising: a base; sensing means, associated with said base, for monitoring the chamber condition and detecting a normal condition an abnormal condition, and an inactive condition; alarm circuit means, associated with said base, for generating signals indicative of the chamber condition, including: switching means operatively connected to said alarm circuit means and responsive to said sensing means for de-energizing said alarm circuit means when said sensing means detects a normal condition and energizing said alarm circuit means when said sensing means detects an abnormal condition; and power supply means operatively connected to power said switching means and said alarm circuit means, said operative connection of said power supply means being disconnectable when said inactive condition is detected.
Claim 3
Dependent Claim
57 words
The device of claim 1, wherein: said switching means comprises a first switch for de-energizing and energizing said alarm circuit means responsive to said sensing means detecting a normal or abnormal condition within the chamber; and said switching means comprises a second switch for de-energizing said first switch responsive to said sensing means detecting an off-line condition.
Claim 4
Dependent Claim
37 words
The device of claim 2, wherein said sensing means comprises: a first sensor for detecting a normal condition and an abnormal condition within the chamber; and a second sensor for detecting an off-line condition within the chamber.
Claim 5
Dependent Claim
15 words
The device of claim 3, wherein said first switch and said second switch are gold-plated.
Claim 6
Dependent Claim
106 words
The device of claim 4, wherein: said first sensor comprises a high pressure bellows, whereby said high pressure bellows compresses to a normal position when the chamber condition increases to normal pressure and said high pressure bellows expands to an alarm position when the chamber condition reduces to alarm pressure; and said second sensor comprises a low pressure bellows, whereby said low pressure bellows expands to an off-line position when the chamber condition reduces to off-line pressure and said low pressure bellows compresses to an activated position when the chamber condition increases to activation pressure, and wherein said alarm pressure is greater than said activation pressure.
Claim 7
Dependent Claim
34 words
The device of claim 5, wherein said alarm circuit means further includes means for prolonging the life of said power supply means by preventing said power supply means from forming a passivation layer thereon.
Claim 8
Dependent Claim
44 words
The device of claim 6 further comprising receiver means, and wherein said circuit means comprises transmitter means, whereby said receiver means cooperates with said transmitter means to provide an alert perceptible to the human senses when an abnormal condition is sensed in the chamber.
Claim 9
Dependent Claim
45 words
The device of claim 7, wherein: said power supply means comprises a battery; and said prolonging means comprises a thermistor operatively connected to said battery to provide a small electrical current draw on said battery, said current draw responsive to the temperature of said battery.
Claim 10
Dependent Claim
27 words
The device of claim 8, further comprising means for mounting said base, said sensing means, said alarm circuit means and said power supply means within the chamber.
Claim 11
Dependent Claim
29 words
The device of claim 9, further comprising a casing disposed over substantially the entirety of said base, said sensing means, said alarm circuit means and said power supply means.
Claim 12
Dependent Claim
128 words
An improved vehicle pneumatic tire pressure sensor and low pressure alert system, comprising: at least one transmitter means, each said transmitter means comprising: a base; a first sensor associated with said base for detecting a normal pressure condition and an abnormal pressure condition surrounding said transmitter; a second sensor associated with said base for detecting an inactive pressure condition of a tire surrounding said transmitter; alarm circuit means, associated with said base, for generating signals responsive to said first sensor and said second sensor; and power supply means operatively connected to power said alarm circuit means, said operative condition being disconnectable when said inactive pressure condition is detected; and at least one receiver means configured to provide alerts perceptible to the human senses responsive to said transmitter means.
Claim 13
Dependent Claim
128 words
An improved vehicle pneumatic tire pressure sensor and low pressure alert system, comprising: at least one transmitter means, each said transmitter means comprising: a base; a first sensor associated with said base for detecting a normal pressure condition and an abnormal pressure condition surrounding said transmitter; a second sensor associated with said base for detecting an inactive pressure condition of a tire surrounding said transmitter; alarm circuit means, associated with said base, for generating signals responsive to said first sensor and said second sensor; and power supply means operatively connected to power said alarm circuit means, said operative condition being disconnectable when said inactive pressure condition is detected; and at least one receiver means configured to provide alerts perceptible to the human senses responsive to said transmitter means.
Claim 14
Dependent Claim
19 words
The system of claim 11, further comprising means for mounting said at least one transmitter within the pneumatic tire.
Claim 15
Dependent Claim
60 words
The system of claim 12, further comprising a first switch and a second switch, said first and second switches operatively connected to said alarm circuit means wherein said first switch is responsive to said first sensor to energize and de-energize said alarm circuit means and said second switch is responsive to said second sensor to de-energize said alarm circuit means.
Claim 16
Dependent Claim
21 words
The system of claim 13, further comprising a casing disposed over substantially the entirety of each said at least one transmitter.
Claim 17
Dependent Claim
49 words
The system of claim 14, wherein: said first and second switches are gold-plated; and said alarm circuit means further comprises a thermistor means operatively connected to said power supply means for drawing a small current on said power supply means responsive to the temperature of said power supply means.
Claim 18
Dependent Claim
123 words
An improved method for sensing a pressure of a pneumatic chamber, comprising the steps of: monitoring the chamber pressure condition for a normal pressure condition, an abnormal pressure condition and an inactive pressure condition; switching responsive to said monitoring to de-energize an alarm circuit means when either the normal pressure condition or the inactive pressure condition is detected and to energize said alarm circuit means when the abnormal pressure condition is detected; disconnecting the alarm circuit means from a power supply when the inactive condition is detected; generating an alarm signal; encoding said alarm signal; transmitting said alarm signal; receiving said alarm signal; decoding said received alarm signal; and displaying an alarm, responsive to said receiving, that is perceptible to the human senses.
Claim 19
Dependent Claim
123 words
An improved method for sensing a pressure of a pneumatic chamber, comprising the steps of: monitoring the chamber pressure condition for a normal pressure condition, an abnormal pressure condition and an inactive pressure condition; switching responsive to said monitoring to de-energize an alarm circuit means when either the normal pressure condition or the inactive pressure condition is detected and to energize said alarm circuit means when the abnormal pressure condition is detected; disconnecting the alarm circuit means from a power supply when the inactive condition is detected; generating an alarm signal; encoding said alarm signal; transmitting said alarm signal; receiving said alarm signal; decoding said received alarm signal; and displaying an alarm, responsive to said receiving, that is perceptible to the human senses.
Claim 20
Dependent Claim
28 words
The method of claim 16, further comprising: installing a sensor-transmitter means within the pneumatic chamber; and whereby said sensor-transmitter performs said monitoring, switching, generating, encoding and transmitting steps.
Claim 21
Dependent Claim
36 words
The method of claim 17, wherein: said sensor-transmitter further comprises a battery; and further comprising the step of drawing a temperature-variable current on said battery whereby buildup of a passivation layer on said battery is retarded.
Claim 22
Dependent Claim
26 words
The method of claim 18, further comprising the step of pulsing said alarm signal, prior to said transmitting, for about 1/3 second every about 15 seconds.
Claim 23
Dependent Claim
28 words
The method of claim 19, further comprising the step of stretching said received signal, prior to said displaying, from about 1/3 second to about 10 seconds in duration.
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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) | 2002-05-03 | 2002-11-02 | 2003-05-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-05-03 | 2006-11-02 | 2007-05-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-05-03 | 2010-11-02 | 2011-05-04 | $7700.00 | Window Closed / Lapsed |