Process for detecting anomalies by use of pressure and temperature measurements in a tire-monitoring device

Claim 2

A process for monitoring parameters relative to wheels of a vehicle, comprising the steps of: substantially simultaneously measuring pressure and temperature values in tires mounted on each of the wheels of the vehicle; calculating a ratio of the measured pressure to the measured temperature for each of the tires; comparing said ratio for one of the tires with said ratio for at least another one of the tires; and outputting an alarm when a result N of said comparison deviates from a predetermined range of values.

Claim 3

The process of claim 1 wherein said comparing step comprises: adding said ratio for a tire mounted on a wheel of one axle of said vehicle and said ratio of at least one tire mounted on a wheel of at least one other axle of said vehicle to produce a first sum S1; adding said ratio for another tire mounted on a wheel of said one axle and said ratio for at least one other tire mounted on a wheel of at least one other axle of said vehicle to produce at least one second sum S2; and calculating said result N as S1/S2.

Claim 4

The process of claim 2 wherein said outputting step comprises outputting an alarm when |N-1|>a predetermined value.

Claim 5

The process of claim 1, wherein said comparing step comprises calculating N, wherein: ##EQU3## where: P is the absolute pressure in a tire, T is the absolute temperature in a tire, AVG refers to the left front tire, AVD refers to the right front tire, ARG refers to the left rear tire, and ARD refers to the right rear tire.

Claim 6

The process of claim 4 wherein said outputting step comprises outputting an alarm when |N-1|>a predetermined value.

Claim 7

The process of claim 4 including the step of filtering the calculated value of N for each time period ti and outputting said alarm only when the filtered value of |N-1|>a predetermined value.

Claim 8

The process of claim 6 including the steps of: calculating values NV, NR, NG and ND, where: ##EQU4## issuing an alarm indicating a anomaly in the left front tire when |N-1|>a predetermined value x and at least one of the following conditions is found: |NV-1|>predetermined value y |NG-1|>predetermined value z; issuing an alarm indicating an anomaly in the right front tire when |N-1|>x and at least one of the following conditions is found: |NV-1|>y |ND-1|>z; issuing an alarm indicating an anomaly in the left rear tire when |N-1|>x and at least one of the following conditions is found: |NR-1|>y |NG-1|>z; and issuing an alarm indicating an anomaly in the right rear tire when |N-1|>x and at least one of the following conditions is found: |NR-1|>y |ND-1|>z.

Claim 9

The process of claim 1 wherein said parameters comprise at least anomalies in the total number of moles of gas in a tire mounted on each of said wheels.

Claim 10

The process of claim 3 wherein said predetermined value is 0.02.

Claim 11

The process of claim 5 wherein said predetermined value is 0.02.