Tire Endurance Testing to Ensure Durability

Accurately predicting the speed at which a tire will fail by evaluating its durability. The method involves incrementally increasing the tire's rotation speed while it's running on a drum driven by an electric motor. The motor power is measured at each speed. The rate of power change with respect to speed is calculated. The critical speed where the power rate sharply rises is determined. Failure speed is predicted based on the critical speed.

Source

Enclosed tire wear testing system that allows precise indoor wear testing of tires by controlling environmental conditions inside the test chamber. The system uses a rotatable drum with a tire mounted on a separate spindle connected by flexible bellows. The chamber has separate enclosures for the drum and tire. It has climate control to maintain temperature and humidity levels inside the chamber. Sensors measure temperature and humidity. Air is blown into the chamber if temperature exceeds a threshold and moisture added if humidity falls below a threshold to maintain desired conditions. This allows controlled indoor wear testing without external factors like temperature and humidity affecting the results.

Source

Indoor tire wear testing system that closely replicates outdoor conditions to more accurately predict real-world tire performance. The system uses an enclosed test chamber with a tire mounted on a spindle inside and the test drum outside, connected by flexible bellows. The chamber allows controlled temperature, humidity, and airflow to simulate various environments. Sensors monitor parameters like temperature and humidity inside the chamber. If they fall below thresholds, the system adds moisture or cools the chamber to match outdoor conditions. This allows testing in consistent, repeatable environments to better predict tire wear and performance in various conditions.

Source

Method for generating tire load histories to simulate loads on a tire for indoor testing or computer simulation. The method involves identifying a vehicle test course, driving a vehicle on it, measuring accelerations and speed, generating a virtual test course from the measured data, collecting tire performance info, building a virtual tire, providing vehicle attributes, generating the tire load history by simulating the vehicle on the virtual course, and testing a physical tire against that history.

Source

Indoor tire testing device that allows realistic evaluation of tire performance on various road surfaces without actually driving on roads. The device has a carriage to hold the test wheel and a driving system. The driving system has separate power sources for speed and torque. The test wheel speed matches carriage speed, but torque is applied using a servo motor. This allows independent control of wheel speed and torque for simulation. The carriage travels on a road surface replica. A sensor array detects force distribution under the tire. Multiple profile images capture force distribution for 3 forces. This provides detailed load analysis beyond just average contact pressure. The device allows evaluating tire performance on a wide range of road conditions without actual driving.

Source

Creating a scalable vehicle model (SVM) to accurately test tire wear and performance across a wide range of vehicles, without the need for testing on multiple actual vehicles. The SVM is defined based on vehicle segment characteristics like weight, wheelbase, suspension, etc. This allows predicting forces and angles exerted on a tire by an average vehicle in the segment, which can be used to simulate tire wear on an indoor tester instead of testing on specific vehicles. The SVM is generated through regression functions based on total weight and independent variables like jounce and steering angle.

Source

A method for measuring fatigue durability of tire sidewall cracks by reproducing the cracking conditions in a driving drum tester. The method involves assembling the tire on a wheel and adjusting the air pressure. The tire is then run on the drum tester at specific conditions like speed, load, and time. Periodic inspections check for sidewall cracks. By subjecting the tire to these conditions, it evaluates fatigue endurance of sidewall cracks indoors.

Source

An objective and quantitative method for evaluating the adverse effects of tire temperature on tire durability and deterioration. The method involves calculating a temperature severity number based on tire temperature measurements and detection frequencies. The severity number is determined by computing a contribution coefficient using power functions of temperature and detection frequencies, then applying a predetermined equation. This provides a numerical scale to objectively assess tire temperature impacts on durability and deterioration.

Source

Durability testing method for tires that more accurately replicates real-world tire aging and wear to evaluate tire durability. The method involves artificially accelerating tire aging and wear before subjecting the tire to a drum endurance test. Steps include: 1) Filling the tire with air at slightly above normal pressure in an oxygen-rich environment (90-110% pressure, 30% oxygen) and leaving it at high temperature (70-90°C) for days to cause thermal fatigue. 2) Scraping the tread rubber to simulate wear. This step is essential to match wear patterns seen in real tires. 3) Conducting drum endurance tests on the aged, partially worn tires. The aged tires with simulated wear better match real-world tire durability due to more realistic stresses and wear patterns compared to new tires subjected to drum endurance

Source

A tire durability test method that more accurately replicates tire failures seen in actual use. The method involves periodically changing the load and speed during a drum durability test. This allows reproducing tire failures closer to those seen in the market, as it better replicates the aging and thermal factors that contribute to tire failures. The test involves running a tire on a drum at a fixed speed while applying a fixed load, but periodically varying the load and speed to mimic real-world conditions.

Source

Tire wear test method to accurately evaluate tire wear characteristics in actual driving conditions. It involves pretreating tires before indoor wear testing to replicate outer diameter growth that happens in normal driving. The pretreatment can be dry heat inflation, running at high load/speed, or a combination. This mimics tire expansion in actual use. The indoor testing with controlled load, slip angle, and camber angle allows evaluating wear under standardized conditions. By reproducing outer diameter growth and using specific test parameters, the test more closely matches real-world wear.

Source

A tire durability test method to accurately evaluate and reproduce internal failures that occur in tires used in hot climates. The test involves gradually increasing test speed or load over extended periods to replicate the thermal oxidative fatigue and load cycling conditions that degrade tires in hot environments. This improves accuracy compared to constant speed/load tests. Additionally, filling the tire with oxygen-rich gas during the main test promotes deterioration and eliminates a pretreatment step.

Source

Accurately evaluating tire durability when testing tires on a drum-type durability test device by controlling the lateral force and slip angle experienced by the tire during rotation. The method involves running the tire on the drum at a specified load and slip angle, detecting the lateral force generated during rotation, and maintaining the running state while controlling the lateral force or the product of lateral force and slip angle to a desired value. This aims to equalize harshness conditions and better reflect actual driving durability when testing tires on the drum.

Source

Method for testing tire durability that accurately reproduces and evaluates tire wear after actual driving conditions. The test involves pretreatment running at reduced air pressure and load variations to promote wear, followed by a normal durability test at standard pressure and load. This shortens test time and more closely replicates real-world tire degradation compared to just running at standard conditions.

Source

A tire durability testing method to more accurately evaluate tire longevity and identify specific areas for improvement. The method involves running a tire on a drum tester until it begins to deform significantly, rather than waiting for complete failure. By measuring deformation at the start of damage, it provides a more realistic representation of tire durability. This allows identification of areas that wear excessively versus those that can handle more load, aiding tire design improvements.

Source

Method for testing run flat tires and components to evaluate their performance and reliability when air pressure is lost. The testing involves accelerating and decelerating the wheel assembly with a run flat tire at controlled speeds and rates to measure any relative rotation between the tire and wheel components like the support ring. This allows quantifying the amount of sliding and wear that occurs during operation when air pressure is low. The testing is repeated at increasing speeds to determine the maximum deceleration rate before relative rotation begins.

Source

A method for consistent tire testing during multiple runs by maintaining constant tire pressure using a pressure-controlling device. The device is mounted on the test tire to prevent pressure variations during dynamic vehicle testing over multiple runs. This ensures consistent tire performance data by compensating for factors like temperature changes that can affect tire pressure during extended testing.

Source