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US4311985A Expired / Lapsed US ⏱️ 0.0 years remaining

Tire pressure monitor and deenergization circuit therefore

Assignee: Eaton Corp
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Filing: 1980-01-15
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Granted: 1982-01-19
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Expires: 2000-01-15
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Abstract

Abstract Tire pressure monitors are incorporated in vehicles having penumatic tires (14) to continuously or periodically measure the air pressure within the tires and to alert the driver should the pressure in one of the tires fall below a predetermined value. A self-contained battery powered rf transmitter unit (10) is affixed within the drop center (22) of each wheel (12) and includes a pressure sensing switch (84). The battery is contained within a housing (20) mounted to the external surface of the wheel adjacent a fill valve (30) through which electrical wires (50) are routed to the transmitter (11). The transmitter emits a pulse every 33 seconds when the air pressure within the tire is above a prescribed value. A receiver (13), located in the passenger compartment of the vehicle, receives the signal(s) from the transmitters and counts the number of signals received over a given time period established by an internal pulse generator. If fewer than a predetermined number of pulses are received during any given time period, a fault condition is indicated and the driver is appropriately warned. The system also has self-check features wherein upon start-up of the associated vehicle, a warning light (320) and buzzer (322) are turned on until the first correct sequence of signals are received from the transmitters. A centrifugal switch interconnects each transmitter with its associated battery only during vehicle operation to prolong battery life.

Inventors

  • 👤 Thomas A. Gee
  • 👤 Donald Speranza

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 14:09
CPC Classifications
B; B60; B60C; B60C23/00; B60C23/02; B60C23/04; B60C23/0408; B60C23/0422; B60C23/0433; B60C23/0491; B60C23/0498; B60C23/04985

Claims Analysis

Total Claims: 20
Claim 1
Independent Claim 92 words
An improved tire pressure monitoring system of the type including a wheel mounted, battery powered transmitter operative to monitor fluid pressure within a pneumatic tire and generate tire inflation condition signals when said pressure falls within a predetermined operating range indicative of normal tire inflation, and a receiver operative to receive said signals and to generate an operator alerting signal in the absence of said signals, said improvement comprising: means independent of said fluid pressure and operative to deenergize said transmitter as a function of the operating condition of an associated vehicle.
Claim 2
Dependent Claim 92 words
An improved tire pressure monitoring system of the type including a wheel mounted, battery powered transmitter operative to monitor fluid pressure within a pneumatic tire and generate tire inflation condition signals when said pressure falls within a predetermined operating range indicative of normal tire inflation, and a receiver operative to receive said signals and to generate an operator alerting signal in the absence of said signals, said improvement comprising: means independent of said fluid pressure and operative to deenergize said transmitter as a function of the operating condition of an associated vehicle.
Claim 3
Dependent Claim 98 words
An improved tire pressure monitoring system of the type including a wheel mounted, battery powered transmitter operative to monitor fluid pressure within a pneumatic tire and generate tire inflation condition signals when said pressure falls within a predetermined operating range indicative of normal tire inflation, and a receiver operative to receive said signals and to generate an operator alerting signal in the absence of said signals, said improvement comprising: wheel mounted switch means independent of said fluid pressure and operative to electrically disconnect said battery and transmitter as a function of the operating condition of an associated vehicle.
Claim 4
Dependent Claim 98 words
An improved tire pressure monitoring system of the type including a wheel mounted, battery powered transmitter operative to monitor fluid pressure within a pneumatic tire and generate tire inflation condition signals when said pressure falls within a predetermined operating range indicative of normal tire inflation, and a receiver operative to receive said signals and to generate an operator alerting signal in the absence of said signals, said improvement comprising: wheel mounted switch means independent of said fluid pressure and operative to electrically disconnect said battery and transmitter as a function of the operating condition of an associated vehicle.
Claim 5
Dependent Claim 41 words
The system of claim 2, wherein said switch means is operative to interconnect said battery and transmitter when the associated vehicle is in the "on" mode and disconnect said battery and transmitter when the associated vehicle is in the "off" mode.
Claim 6
Dependent Claim 22 words
The system of claim 2, wherein said switch means is responsive to rotation of said wheel to interconnect said battery and transmitter.
Claim 7
Dependent Claim 13 words
The system of claim 4, wherein said switch means comprises a centrifugal switch.
Claim 8
Dependent Claim 24 words
The system of claim 5, wherein said switch is mounted on the wheel at a location radially spaced from the wheel's axis of rotation.
Claim 9
Dependent Claim 19 words
The system of claim 5, wherein said switch is mounted within the cavity defined by said wheel and tire.
Claim 10
Dependent Claim 28 words
The system of claim 3, further comprising means operative to disable said receiver from generating said operator alerting signal when the associated vehicle is in the "off" mode.
Claim 11
Dependent Claim 27 words
The system of claim 8, wherein said disabling means is operative to monitor vehicle speed and disable said receiver when said speed falls below a predetermined level.
Claim 12
Dependent Claim 191 words
A tire pressure monitoring system for use with a vehicle having a plurality of pneumatic tires and associated mating wheels, said system comprising: a transmitter associated with each tire, each said transmitter comprising: a battery mounted for rotation with its associated wheel on the external surface thereof; an RF transmitter mounted within the cavity defined by the associated tire and wheel for rotation therewith; and a pressure switch operative to electrically interconnect said battery and transmitter when the fluid pressure within the associated tire substantially equals a predetermined set point level, said transmitter operating during said interconnection to generate a continuing succession of RF tire inflation condition signals; an RF receiver disposed within the chassis of said vehicle and operative to receive and count the tire condition signals received from all of said transmitters, establish a succession of internal timing pulses and generate an operator alerting signal when less than a predetermined number of said tire condition signals are received between two consecutive timing pulses; and switch means associated with each transmitters operative to electrically disconnect said associated battery and transmitter as a function of the operating condition of said vehicle.
Claim 13
Dependent Claim 191 words
A tire pressure monitoring system for use with a vehicle having a plurality of pneumatic tires and associated mating wheels, said system comprising: a transmitter associated with each tire, each said transmitter comprising: a battery mounted for rotation with its associated wheel on the external surface thereof; an RF transmitter mounted within the cavity defined by the associated tire and wheel for rotation therewith; and a pressure switch operative to electrically interconnect said battery and transmitter when the fluid pressure within the associated tire substantially equals a predetermined set point level, said transmitter operating during said interconnection to generate a continuing succession of RF tire inflation condition signals; an RF receiver disposed within the chassis of said vehicle and operative to receive and count the tire condition signals received from all of said transmitters, establish a succession of internal timing pulses and generate an operator alerting signal when less than a predetermined number of said tire condition signals are received between two consecutive timing pulses; and switch means associated with each transmitters operative to electrically disconnect said associated battery and transmitter as a function of the operating condition of said vehicle.
Claim 14
Dependent Claim 41 words
The system of claim 10, wherein each said switch means is operative to interconnect said associated battery and transmitter when the vehicle is in the "on" mode and disconnect said battery and transmitter when said vehicle is in the "off" mode.
Claim 15
Dependent Claim 25 words
The system of claim 10, wherein each said switch means is responsive to rotation of its associated wheel to interconnect said associated battery and transmitter.
Claim 16
Dependent Claim 14 words
The system of claim 12, wherein each said switch means comprises a centrifugal switch.
Claim 17
Dependent Claim 26 words
The system of claim 13, wherein each said switch is mounted on its associated wheel at a location radially spaced from the axis of rotation thereof.
Claim 18
Dependent Claim 21 words
The system of claim 13, wherein each said switch is mounted within the cavity defined by its associated wheel and tire.
Claim 19
Dependent Claim 28 words
The system of claim 11, further comprising means operative to disable said receiver means from generating said operator alerting signal when the vehicle is in the "off" mode.
Claim 20
Dependent Claim 27 words
The system of claim 16, wherein said disabling means is operative to monitor vehicle speed and disable said receiver when said speed falls below a predetermined level.

References Cited (Backward Citations)

US2860321A Cited
US3178686A Cited
US3111644A Cited
US3223969A Cited
US3296590A Cited
US3588815A Cited
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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) 1985-01-18 1985-07-20 1986-01-19 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1989-01-18 1989-07-20 1990-01-19 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1993-01-18 1993-07-20 1994-01-19 $7700.00 Window Closed / Lapsed

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