US3812458A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Power supply with unidirectional current flow for a pneumatic tire low pressure monitoring and warning system
Assignee: Avco Corp
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Filing: 1972-09-15
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Granted: 1974-05-21
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Expires: 1992-09-15
Abstract
Abstract An electrical circuit for eliminating severe voltage fluctuations in a battery power supply and providing a substantially constant voltage to an associated output connection and a pneumatic tire low pressure monitoring and warning system using such circuit is provided. The circuit comprises a diode connected to the power supply with the output connection being connected to a voltage regulator which is in turn connected to receiving means of the system. A storage capacitor is provided and has one end connected between the output connection and ground so that in the event of a sudden voltage drop in power supply the voltage across the diode will be reversed to thereby cease current flow therethrough and allow the storage capacitor to supply the output connection. Current limiting means may be connected between the diode and the output connection.
Inventors
- 👤 C Hill
- 👤 W Brobeck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 05:46
CPC Classifications
B; B60; B60C; B60C23/00; B60C23/02; B60C23/04; B60C23/0408; B60C23/0422; B60C23/0433; G; G05; G05F; G05F1/00; G05F1/10; G05F1/46
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
254 words
In combination a power supply for an RF receiver of a pneumatic tire low pressure monitoring and warning system, said pneumatic tire being attached to an associated vehicle by a rotatable support, said vehicle having a storage battery as the source of power for the electrical equipment of said vehicle; said pneumatic tire low pressure monitoring and warning system comprising: a pressure sensor; a battery powered RF transmitter attached to said rotatable support and rotated therewith; receiving means including an antenna and transmission line; an RF receiver including indicating mEans; said RF transmitter being activated by said pressure sensor in response to a low tire pressure condition in said tire and thereupon generating RF output signals; said RF receiver providing a low pressure indication in response to said RF output signals; said RF receiver being powered by said storage battery in said vehicle and thereby being exposed to the power supply disturbances resulting from the operation of electrical equipment in said vehicle, said RF receiver including a unidirectional power supply comprising: a voltage regulator supplying a substantially constant preselected output voltage to said RF receiver; electrical storage means for the storing of electrical power for use by said voltage regulator; said electrical storage means connected to said storage battery by a unidirectional current circuit thereby assuring that the electrical energy stored in said electrical storage means is reversed for the use of said RF receiver and further assuring that the input voltage to said voltage regulator does not drop below said preselected output voltage.
Claim 2
Dependent Claim
254 words
In combination a power supply for an RF receiver of a pneumatic tire low pressure monitoring and warning system, said pneumatic tire being attached to an associated vehicle by a rotatable support, said vehicle having a storage battery as the source of power for the electrical equipment of said vehicle; said pneumatic tire low pressure monitoring and warning system comprising: a pressure sensor; a battery powered RF transmitter attached to said rotatable support and rotated therewith; receiving means including an antenna and transmission line; an RF receiver including indicating mEans; said RF transmitter being activated by said pressure sensor in response to a low tire pressure condition in said tire and thereupon generating RF output signals; said RF receiver providing a low pressure indication in response to said RF output signals; said RF receiver being powered by said storage battery in said vehicle and thereby being exposed to the power supply disturbances resulting from the operation of electrical equipment in said vehicle, said RF receiver including a unidirectional power supply comprising: a voltage regulator supplying a substantially constant preselected output voltage to said RF receiver; electrical storage means for the storing of electrical power for use by said voltage regulator; said electrical storage means connected to said storage battery by a unidirectional current circuit thereby assuring that the electrical energy stored in said electrical storage means is reversed for the use of said RF receiver and further assuring that the input voltage to said voltage regulator does not drop below said preselected output voltage.
Claim 3
Dependent Claim
115 words
A power supply for an RF receiver as set forth in claim 1 in which said unidirectional current circuit comprises a diode and in which said electrical storage means comprises an electrical capacitor; said diode being connected between said storage battery and one side of said capacitor and to the input of said voltage regulator, the opposite side of said capacitor being connected to ground so that in the event of a sudden drop in the voltage supplied by said storage battery, the voltage across said diode will be reversed to thereby cease the current flow therethrough and thus reserve the electrical energy stored in said capacitor for the sole use of said voltage regulator.
Claim 4
Dependent Claim
51 words
A power supply for an RF receiver as set forth in claim 2 in which current limiting means are connected in series with said diode to insure that the charging current for said capacitor, following a voltage reversal across said diode, does not exceed the maximum allowable current for said diode.
Claim 5
Dependent Claim
22 words
A power supply for an RF receiver as set forth in claim 3 in which said current limiting means comprises a resistor.
Claim 6
Dependent Claim
85 words
A power supply for an RF receiver as set forth in claim 2 in which said voltage regulator comprises: a transistor having collector, emitter and base electrodes and a voltage reference circuit, said voltage reference circuit comprising a Zener diode connected in parallel with a bypass and loading capacitor; said collector electrode being connected to the storage capacitor and exposed to the voltage thereon; and said emitter electrode being connected to said receiving means; and said base electrode being connected to said voltage reference circuit.
Claim 7
Dependent Claim
32 words
A power supply for an RF receiver as set forth in claim 5 in which said bypass and loading capacitor comprises an LF bypass and loading capacitor and an RF bypass capacitor.
Claim 8
Dependent Claim
40 words
A power supply for an RF receiver as set forth in claim 5 in which said voltage regulator further comprises a bleeder resistor connected between said collector and base electrodes to maintain a fixed reference voltage across said Zener diode.
Claim 9
Dependent Claim
60 words
A power supply for an RF receiver as set forth in claim 3 in which said storage battery supply provides an unregulated voltage generally of the order of 15 volts and subject to severe disturbances and said voltage regulator provides a regulated and filtered output voltage generally of the order of 9.0 Volts through the emitter electrode of said transistor.
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) | 1977-05-20 | 1977-11-19 | 1978-05-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-05-20 | 1981-11-19 | 1982-05-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-05-20 | 1985-11-19 | 1986-05-21 | $7700.00 | Window Closed / Lapsed |