EP0108176A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Detection of a low pressure condition of a pneumatic vehicle tyre
Assignee: Individual
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Filing: 1982-11-05
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Granted: —
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Expires: 2002-11-05
Abstract
Abstract A tyre pressure warning device including an oscillatory circuit (16) mounted on the rim of a vehicle wheel (12). A pressure sensing device (14) adjusts the natural frequency of oscillations of the circuit (16) according to the tyre (10) pressure. The circuit (16) is driven into oscillation by a transmitting coil (20) and the frequency of oscillation is sensed via a coil (22) and electrical circuits (30), (32), (34) and (36), which give a visual or audible signal which can be arranged to control automatically the inflation or deflation of the tyre (10). The device is arranged to selectively measure the conditions of two or more tyres of a vehicle.
Inventors
- 👤 Frans Johannes Kruger
- 👤 Philip Elliot Galasko
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 05:51
CPC Classifications
B; B60; B60C; B60C23/00; B60C23/02; B60C23/04; B60C23/0408; B60C23/0422; B60C23/0427; B60C23/0428
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
75 words
A device for measuring variable conditions of a rotatable member including mounted on the rotatable member an electrical oscillatory circuit and condition monitoring means arranged to adjust the natural frequency of oscillations of the circuit in response to changes in a condition to be measured, and a frequency detector circuit positioned adjacent the rotatable member to sense the frequency of oscillations of the oscillatory circuit and to provide an output corresponding to the measured condition.
Claim 2
Independent Claim
75 words
A device for measuring variable conditions of a rotatable member including mounted on the rotatable member an electrical oscillatory circuit and condition monitoring means arranged to adjust the natural frequency of oscillations of the circuit in response to changes in a condition to be measured, and a frequency detector circuit positioned adjacent the rotatable member to sense the frequency of oscillations of the oscillatory circuit and to provide an output corresponding to the measured condition.
Claim 3
Dependent Claim
41 words
A device according to Claim 1 for measuring the condition of a vehicle tyre in which the oscillatory circuit is mounted to sense the condition of the tyre and the detector circuit is secured to a structural member of the vehicle.
Claim 4
Dependent Claim
30 words
A device according to Claim 2 in which the condition monitoring means comprises an air pressure sensing device which is arranged to adjust a capacitive component of the oscillatory circuit.
Claim 5
Dependent Claim
36 words
A device according to Claim 3, in which the oscillatory circuit has separate capacitive devices arranged to be selectively switched into the oscillatory circuit and the pressure sensing device is arranged to control the selective switching.
Claim 6
Independent Claim
41 words
A device according to any one of Claims 2 to 4, fitted to measure the condition of two or more tyres of a vehicle and including switching means for selectively providing the outputs of the measured condition at a central console.
Claim 7
Dependent Claim
39 words
A device according to Claim 5, in which a single frequency detector circuit is arranged to be selectively switched to measure the frequency of oscillations of a number of oscillatory circuits, one oscillatory circuit being provided for each tyre.
Claim 8
Independent Claim
28 words
A device according .to any one of Claims 2 to 6, in which the output signal is arranged to control automatically the inflation or deflation of the tyre.
Claim 9
Independent Claim
35 words
A device according to any one of Claims 2 to 6, in which the output signal is arranged to produce a warning signal whenever its value differs from a predetermined value or range of values.
Claim 10
Dependent Claim
15 words
A device according to Claim 8 in which the warning signal is a visual signal.
Claim 11
Dependent Claim
15 words
A device according to Claim 8 in which the warning signal is an audible signal.
References Cited (Backward Citations)
US2274557A
Cited
FR2344007A1
Cited
FR2434718A1
Cited
DE2854772A1
Cited
FR2454382A1
Cited
GB2065896A
Cited
GB2069209A
Cited
EP0045401A2
Cited
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