Method for selecting a tire set from a group of experimental tires

• US 6,466,878 B1
• Filed: 06/07/1999
• Issued: 10/15/2002
• Est. Priority Date: 12/27/1996
• Status: Expired due to Fees

• Current Assignee: Goodyear Tire & Rubber Company
• Original Assignee: Goodyear Tire & Rubber Company
• Inventors: Breedijk, Frans Nico
• Primary Examiner(s): Hilten, John S.
• Assistant Examiner(s): Myster, Jacquelyn M.
• Application Number:
  US09/319,672
• Time in Patent Office: 1,226 Days
• Field of Search: 702/41, 731/46, 700/279
• US Class Current: 702/41
• CPC Class Codes: G01M 17/022 the tyre co-operating with rotatable rolls

Abstract

A method for selecting one or more sets of experimental tires of one construction based on the residual forces on each axle and the position that each individual tire is mounted to a vehicle. The method selects sets of tires where predefined limits relating to the residual forces on the front and rear axles are met. The advantage of this method is the ability to select matched sets of tires from a larger group of experimentally built tires so that the performance of the matched set(s) will behave as randomly chosen sets from uniform production runs.

Claims

1. A method for selecting a representative set of tires from a group of experimental tires having a single tire construction, said representative set of tires comprising a grouping of a front pair of tires for mounting on a front axle of a vehicle with a rear pair of tires for mounting on a rear axle of said vehicle, said method comprising the steps of:

a) calculating a residual force on said front axle (RESF) at a first tire deflection and a residual force on said rear axle (RESR) at said first tire deflection for a plurality of front pairs and rear pairs of tires from said group of experimental tires, and selecting first groupings of front pairs with rear pairs such that said RESR at said first tire deflection is equal to or a predetermined amount greater than said RESF at said first tire deflection;

b) calculating an RESF for a plurality of front pairs at a second tire deflection that is greater than said first tire deflection, and calculating an RESR for a plurality of rear pairs at said second tire deflection, and selecting second groupings of front pairs with rear pairs such that the absolute value of said RESR at said second tire deflection is equal to or a predetermined amount greater than the absolute value of said RESF at said second tire deflection, and the absolute value of said RESF at said second tire deflection is equal to or greater than the absolute value of said RESF at said first tire deflection;

c) selecting third groupings of front pairs with rear pairs such that said RESF at said first tire deflection and said RESR at said first tire deflection are each either greater than a predetermined maximum value or less than a predetermined minimum value; and

d) selecting said representative set of tires such that said representative set of tires is a grouping of front pairs with rear pairs that is simultaneously one of said first groupings, one of said second groupings, and one of said third groupings.

2. The method of claim 1 including the steps of determining, for each of a plurality of tires from said group of experimental tires:

the average lateral force (LF1) in the clockwise (CW) direction and the average lateral force (LF2) in the counterclockwise (CCW) direction, for both said first tire deflection and said second tire deflection.

3. The method of claim 2 further including the steps of:

measuring conicity and plysteer of each of said plurality of tires in the CW and CCW directions at said first tire deflection corresponding to a first load of about 80% to about 120% of a normal load on a tire uniformity machine, wherein said normal load is a loading force that is normally applied to a tire while mounted on said vehicle;

measuring the conicity and plysteer of each of said plurality of tires in the CW and CCW directions at said second tire deflection corresponding to a second load of about 130% to about 170% of said first load on said tire uniformity machine;

calculating said conicity and plysteer for said first and second loads from the equations;

4. The method of claim 3 further including the steps of:

measuring the conicity and plysteer at said first load corresponding to about 90% to about 110% of said normal load, and

measuring the conicity and plysteer at said second load corresponding to about 140% to about 160% of said normal load.

5. The method of claim 4 further including the steps of:

measuring the conicity and plysteer at said first load corresponding to about 100% of said normal load, and

measuring the conicity and plysteer at said second load corresponding to about 150% of said normal load.

6. The method of claim 1 wherein selecting first groupings of pairs of tires in step a) is such that said RESR at said first tire deflection is between about 0 to about 4 pounds greater than said RESF at said first tire deflection.

7. The method of claim 1 wherein selecting second groupings of pairs of tires in step b) is such that said RESF and said RESR at said second tire deflection are within a predetermined range of values of about −

4.0 to 4.0 pounds.

8. The method of claim 1 wherein selecting third groupings of pairs of tires in step c) is such that said RESF at said first tire deflection and said RESR at said first tire deflection are greater than about 3.0 lbs or less than about −

3.0 lbs.

9. The method of claim 1 wherein selecting first groupings of pairs of tires in step a) is such that said RESR at said first tire deflection is greater than a predetermined amount above said RESF at said first tire deflection.

10. The method of claim 1 wherein selecting first groupings of pairs of tires in step a) is such that said RESR at said first tire deflection is between about 0 and about 2 pounds greater than said RESF at said first tire deflection.