Abstract: A device, and an analogous method and program, for detecting whether different tires are mounted on the left and right driving wheels of a vehicle and accurately detecting decreased tire pressures. The device detects the rotational speeds of wheels mounted on the vehicle, detects torque applied to driving wheels, and calculates the inclinations of straight lines representing (1) the relation between the rotational speed ratio of the front and rear left side wheels and torque applied to driving wheels and (2) the relation between the rotational speed ratio of the front and rear left side wheels and torque applied to driving wheels. The device compares the inclinations of the lines to detect whether different tires are mounted on the driving wheels. Based on the comparison of the inclinations, the device changes the threshold for judging tire deflation to different values for different tires and tires that are not different.

Abstract: It is the purpose of the present invention to provide a method, apparatus and program for alarming abnormality in tire air-pressure capable of precisely detecting decrease in tire air-pressure even at actuation of air suspension in a vehicle equipped with air suspensions. The present invention discloses a method for alarming abnormality in tire air-pressure informing decrease in tire air-pressure mounted on a vehicle, comprising a step of judging whether loads applied on respective tires are changed by the influence of air suspensions based on the difference of the heights of strokes between left wheel and right wheel in a vehicle equipped with the air suspensions and affect the rotational wheel speeds of tires or not, and increasing threshold for carrying out the judgment of decrease in tire air-pressure when the air suspensions provide influence.

Abstract: A tire deflation warning system, including a device for detecting a rotational velocity of a wheel attached to a vehicle and a device for judging a tire pneumatic pressure drop by determining a reduced pressure judging value that judges the tire pneumatic pressure drop made of difference of rotational velocity sum of two pairs of the wheels which are diagonally disposed in the vehicle, correcting the reduced pressure judging value by multiplying a weight coefficient that continuously varies according to the velocity of the vehicle, and comparing the corrected reduced pressure judging value with a threshold value, wherein it is tentatively judged whether or not there is a reduced pressure wheel; and in the case when it is tentatively judged that a driving wheel is being reduced pressure, the reduced pressure judging value is multiplied by the weight coefficient which is larger than in the case when it is tentatively judged that a driven wheel is being reduced pressure.

Abstract: The present invention provides an apparatus, method and program for alarming abnormality in tire air-pressure which prevent the issuance of an erroneous alarm and thus determine abnormality in tire air-pressure even when a rotational velocity of the tire changes by causes other than a decrease in an air pressure. An apparatus for alarming abnormality in tire air-pressure decrease includes means for detecting a change in a relationship between wheel velocities of front wheel tires and those of rear wheel tires, and means for replacing a relationship between the wheel velocities of the front wheel tires and those of the rear wheel tires with a relationship between wheel velocities of front wheel tires and those of rear wheel tires obtained after the change of the relationship, thereby determining abnormality in air-pressure when the change is detected in the detecting means.

Abstract: The present invention provides an apparatus, method and program for alarming abnormality in tire air-pressure which detects abnormality of a tire even under unusual conditions such as offset load on a vehicle or providing a snow chain on one wheel. The apparatus, method and program for alarming abnormality in tire air-pressure include means of comparing rotational wheel velocities of respective tires provided on a vehicle and detecting whether or not rotational wheel velocity of one wheel is slower than those of other wheels by comparing rotational wheel velocities of respective tires provided on a vehicle.

Abstract: The present invention provides an apparatus, method and program for detecting abnormality in tire air-pressure which allow detecting abnormality in tire air-pressure even if pressure in a tire is completely zero. The apparatus for alarming abnormality in tire air-pressure includes means of (1) calculating the acceleration variations of respective tires from accelerations of the tires calculated by rotational wheel velocities; (2) comparing the calculated acceleration variations of the respective tires; and (3) detecting air-pressure in a tire is abnormal when the acceleration variation of the tire is larger than the acceleration variations of the remaining tires as a result of comparison.

Abstract: A method, an apparatus and a program for alarming abnormality in tire air-pressure which enables to prevent issuing a eroneous alarm or no alarm when only one tire is replaced with a new tire can be provided. The method of alarming abnormality in tire air-pressure includes a step of detecting whether or not a new tire has been mounted by comparing the difference between determinate values to judge a decrease in air-pressure before and after enlargement of a diameter of the new tire with a set threshold value when solely one tire is replaced with the new tire with the use of a phenomenon that a diameter of a new tire on a vehicle enlarges after running.

Abstract: An object of the present invention is to provide a device for detecting as to whether or not the heterogeneous tires are set on the right and left wheels, respectively, and accurately detecting the loss of the pneumatic pressure in the tire, even when heterogeneous tires are set on the right and the left wheels, respectively.

Abstract: To provide a device for detecting whether heterogeneous tires are mounted on the respective left and right driving wheels or not and accurately detecting the decreased tire pressures.

Abstract: A tire deflation warning system, including a means for detecting a rotational velocity of a wheel attached to a vehicle and a means for judging a tire pneumatic pressure drop by determining a reduced pressure judging value that judges the tire pneumatic pressure drop made of difference of rotational velocity sum of two pairs of the wheels which are diagonally disposed in the vehicle, correcting the reduced pressure judging value by multiplying a weight coefficient that continuously varies according to the velocity of the vehicle, and comparing the corrected reduced pressure judging value with a threshold value, wherein it is tentatively judged whether or not there is a reduced pressure wheel; and in the case when it is tentatively judged that a driving wheel is being reduced pressure, the reduced pressure judging value is multiplied by the weight coefficient which is larger than in the case when it is tentatively judged that a driven wheel is being reduced pressure.

Abstract: A tire deflation detection system for determining loss of air pressure in a tire through comparing a determination value, which determines the loss of air pressure in the tire based on information of wheel speed of a vehicle, with a threshold value, wherein a determination threshold value for determining a position of the tire in low air pressure is modulated in accordance with velocity of said vehicle.

Abstract: A method for detecting decrease in tire air-pressure in which decrease in internal pressure of a tire is detected on the basis of rotational information obtained from tires attached to a vehicle. The method includes the steps of: detecting rotational information of the respective tires; storing the rotational information of the respective tires; obtaining a slip rate between the tires and a road surface during running; comparing the slip rate with a slip rate which has been preliminarily obtained when at normal internal pressure; and judging simultaneous decompression of two wheel tires of both front wheels or simultaneous decompression of two wheel tires of both rear wheels on the basis of a relationship between a value obtained through comparison of the two slip rates and a specified threshold. It is possible to judge simultaneous decompression of two wheel tires of both front wheels or wheel two tires of both rear wheels.

Abstract: A method for detecting decrease in tire air-pressure on the basis of rotational information obtained from tires attached to a vehicle. The method includes the steps of: detecting rotational information of the respective tires; storing the rotational information of the respective tires; obtaining an acceleration/deceleration of the vehicle; obtaining a slip rate when the acceleration/deceleration of the vehicle is within a specified range proximate to zero; comparing the slip rate with a slip rate which has been preliminarily obtained when the tire is under normal air pressure; and judging simultaneous decompression of both front wheel tires or simultaneous decompression of both rear wheel tires on the basis of a relationship between a value obtained through comparison of the two slip rates and a specified threshold. It is possible to judge simultaneous decompression of both front wheel tires or both rear wheel tires when employing the present invention.

Abstract: A method for detecting decrease in tire air-pressure in which decrease in internal pressure of a tire is detected on the basis of rotational information. The method includes the steps of: detecting rotational information of the tires; storing the rotational information; comparing rotational information of all left-sided wheels and rotational information of all right-sided wheels of the vehicle when the vehicle is performing straight-ahead running; and judging decompression on the basis of a relationship between a value obtained through comparison of the left-sided and right-sided rotational information and a specified threshold. It is possible to detect decompression of a single wheel tire while it is also possible to detect that two wheel tires on the left or right are simultaneously decreased.

Abstract: An apparatus for calculating an initial correction coefficient for correcting rotational angular velocities obtained from outputs of rotational angular velocity detecting means. The apparatus includes a judged value calculating means which calculates a judged value on the basis of the rotational angular velocities; an identifying means which identifies whether the vehicle is performing turning movements at high velocity, straight-ahead running or turning movements at mid/low velocity; and an initial correction coefficient calculating means which obtains an initial correction coefficient when it has been identified by the identifying means that the vehicle is performing straight-ahead running or turning movements at mid/low velocity. It is possible to obtain accurate correction coefficients so that it is possible to accurately detect, for instance, a decrease in tire air-pressure and thus to maintain safe running.

Abstract: A method for detecting decrease in tire air-pressure in which decrease in internal pressure of a tire is detected on the basis of rotational information obtained from tires attached to a vehicle.

Abstract: A method for detecting decrease in tire air-pressure for detecting decrease in internal pressure of a tire on the basis of rotational information obtained from tires attached to a vehicle. A threshold for judging decrease in air-pressure of following wheels is different from a threshold for judging decrease in air-pressure of driving wheels. Threshold for judging abnormalities in air-pressure are varied for judging abnormalities of tire air-pressures of following wheels and for judging abnormalities of tire air-pressure of driving wheels so that appropriate judgment of abnormalities in air-pressure can be performed.

Abstract: A method for detecting decrease in tire air-pressure including the steps of: detecting rotational information of the respective tires; storing rotational information; detecting whether the vehicle is running on a flat road or not; detecting whether the vehicle is accelerating or decelerating; comparing rotational information of both front wheels with rotational information of both rear wheels when it has been determined that the vehicle is running on a flat road and that the vehicle is neither accelerating nor decelerating; and judging simultaneous decompression of both front wheel tires or simultaneous decompression of both rear wheel tires on the basis of a relationship between a value obtained through comparison of the rotational information of both front wheels and both rear wheels and a specified threshold. It is possible to judge simultaneous decompression of both front wheel tires or both rear wheel tires when employing the present invention.

Abstract: A method for detecting decrease in tire air-pressure in which decrease in internal pressure of a tire is detected on the basis of rotational information obtained from tires attached to a vehicle. The method includes the steps of: detecting rotational information of the respective tires; storing the rotational information of the respective tires; obtaining a slip rate between the tires and a road surface during running; comparing the slip rate with a slip rate which has been preliminarily obtained when at normal internal pressure; and judging simultaneous decompression of two wheel tires of both front wheels or simultaneous decompression of two wheel tires of both rear wheels on the basis of a relationship between a value obtained through comparison of the two slip rates and a specified threshold. It is possible to judge simultaneous decompression of two wheel tires of both front wheels or wheel two tires of both rear wheels.

Abstract: A method for detecting decrease in tire air-pressure in which decrease in internal pressure of a tire is detected on the basis of rotational information obtained from tires attached to a vehicle.