Method of detecting configuration of tire

• US 4,783,992 A
• Filed: 06/26/1987
• Issued: 11/15/1988
• Est. Priority Date: 06/26/1987
• Status: Expired due to Term

• Current Assignee: Bridgestone Corporation
• Original Assignee: Bridgestone Corporation
• Inventors: Ishibashi, Akira
• Primary Examiner(s): Woodiel, Donald O.
• Application Number:
  US07/066,440
• Time in Patent Office: 508 Days
• Field of Search: 73/146, 33/203.11, 33/203.12
• US Class Current: 73/146
• CPC Class Codes: G01M 17/02 Tyres

Abstract

In a method of detecting an outer configuration of a side wall surface of an inflated tire, a distance between a sensor and the side wall surface is detected in a non-contact manner to derive a displacement signal, the displacement signal is converted into a digital displacement signal and successive peaks of the digital displacement signal are detected. Heights h_n and distances l_n between successive peak points are derived and areas AS_n and BS_n surrounded by the displacement signal and a rectangle whose corners are coincident with adjacent peak points are derived. The heights h_n, distances l_n are areas AS_n, BS_n are compared with threshold values h_R, l_R and AS_R, BS_R, respectively. When h_n >h_R, l_n <l_R and AS_n >AS_R or BS_n >BS_R, a relevant tire is judged to be inferior.

Claims

1. A method of detecting an outer configuration of a surface of an inflated tire comprising the steps of:

rotating the inflated tire through a sensor which can measure a distance between the sensor and the surface of tire in a non-contact manner to derive an analog displacement signal;

converting the analog displacement signal into a digital displacement signal;

storing the digital displacement signal in relation to a rotational position of the tire;

deriving peak points of the digital displacement signal;

detecting an outer configuration of a surface of tire in accordance with the detected peak points by deriving heights h_n between successive peak points;

deriving distance l_n between successive peak points;

deriving first and second areas AS_n and BS_n surrounded by the displacement signal and a rectangle whose opposite corners are coincided with successive peak points; and

comparing said heights h_n, distances l_n and areas AS_n and BS_n with threshold values h_R, l_R and AS_R and BS_R, respectively.

2. A method according to claim 1, wherein said sensor is arranged opposite to a side wall of said tire to measure a distance between the sensor and a surface of the side wall of said tire.

3. A method according to claim 1, wherein when H_n >

h_R, l_n <

l_R and AS_n >

AS_R or BS_n >

BS_R, a relevant tire is judged to be inferior.

4. A method according to claim 3, wherein said threshold values h_R, l_R, AS_R and BS_R are changed in accordance with a king of a tire.

5. A method of detecting an outer configuration of a surface of an inflated tire comprising the steps of:

rotating the inflated tire through a sensor which can measure a distance between the sensor and the surface of tire in a non-contact manner to derive an analog displacement signal;

converting the analog displacement signal into a digital displacement signal;

storing the digital displacement signal in relation to a rotational position of the tire;

deriving peak points of the digital displacement signal;

detecting an outer configuration of a surface of tire in accordance with the detected peak points; and

deriving points of inflection I_n of the displacement signal, whereby the outer configuration of tire is detected in accordance with the peak points and points of inflection.

6. A method according to claim 5, wherein said sensor is arranged opposite to a sidewall of said tire to measure a distance between the sensor and a surface of the sidewall of said tire.

7. A method of detecting an outer configuration of a surface of an inflated tire comprising the steps of:

rotating the inflated tire through a sensor which can measure a distance between the sensor and the surface of tire in a non-contact manner to derive an analog displacement signal;

said sensor is arranged in opposition to a tread surface of tire to measure a distance between the sensor and the tread surface of tire;

converting the analog displacement signal into a digital displacement signal;

storing the digital displacement signal in relation to a rotational position of the tire;

deriving peak points of the digital displacement signal; and

detecting an outer configuration of a surface of tire in accordance with the detected peak points.