JP2019014446A - Control apparatus - Google Patents

Abstract

To provide a control apparatus capable of properly performing tire rotation.SOLUTION: A control apparatus comprises an input part into which information on how to use a plurality of tires attached to a vehicle is input, and a calculation part that calculates a residual travel distance until differences among groove depths among the plurality of tires exceed a predetermined allowance, on the basis of the information on how to use the tires. For example, the information on how to use the tires includes at least one of tire air pressure, the number of times of steering, a steering speed, an axle load, a vehicle speed, vehicle acceleration, vehicle deceleration, an engine torque output value and lateral acceleration of the vehicle.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to a control device.

  For example, by performing a tire rotation that changes the position of the tire in the vehicle, the wear state of each tire can be made uniform, and further, it can be prevented from being reduced. Thereby, the lifetime of a tire can be extended.

  For example, the tire rotation is performed by a predetermined method when a predetermined travel distance is reached.

JP 2005-324578 A

  By the way, the way tires are used differs between vehicles. For this reason, even if the mileage is the same between vehicles, the amount of tire wear differs. As a result, tire rotation may be performed even in a vehicle with a small amount of tire wear. On the other hand, tire rotation may not be performed even for a vehicle with a large amount of tire wear.

  Further, depending on how the tire is used, the position of a tire with a relatively large amount of wear and the position of a tire with a relatively small amount of wear differ between vehicles. As a result, when tire rotation is performed by a predetermined method, tires with a relatively large amount of wear may be replaced with each other or tires with a relatively small amount of wear may be replaced with each other. May not be done.

  The objective of this indication is providing the control apparatus which can perform tire rotation appropriately.

The control device of the present disclosure includes:
An input unit for inputting information on how to use a plurality of tires mounted on the vehicle;
Based on information on how to use the tire, a calculation unit that calculates a remaining travel distance until a difference in groove depth between the plurality of tires exceeds a predetermined allowable value;
Is provided.

  According to the present disclosure, tire rotation can be appropriately performed.

The block diagram which showed an example of the structure of the control apparatus which concerns on one embodiment of this indication A graph showing the relationship between mileage and tire groove depth Flow chart showing tire rotation support process

  Hereinafter, the control apparatus 1 which concerns on one embodiment of this invention is demonstrated in detail with reference to drawings. FIG. 1 is a diagram illustrating an example of the configuration of the control device 1 according to the present embodiment.

  In the present embodiment, a case where the control device 1 is applied to a four-wheeled vehicle will be described. In the four-wheeled vehicle, the right front wheel, the left front wheel, the right rear wheel, and the left rear wheel are suspended from the vehicle body by a suspension. In the following description, tire air pressure refers to tire air pressure at each wheel.

  As shown in FIG. 1, the control device 1 includes an ECU 10, an input unit 100, and a notification unit 50.

  ECU10 is an apparatus which controls each system in a vehicle using an electronic circuit. The ECU 10 includes a calculation unit 20, a storage unit 30, and an output unit 40.

  The input unit 100 acquires information on how the tire is used in each wheel. In addition, the acquisition of information on how tires are used (hereinafter referred to as related information) includes cases where the information is acquired directly for each tire, and related information is acquired, and a predetermined calculation is performed based on the related information. It may be calculated for each tire with reference to the formula.

  The input unit 100 includes a tire air pressure acquisition unit 11, a steering steering number acquisition unit 12, a steering steering speed acquisition unit 13, a vehicle lateral G acquisition unit 14, a vehicle deceleration acquisition unit 15, and an engine torque output value acquisition unit 16.

  The tire air pressure acquisition unit 11 acquires the tire air pressure every predetermined time. The air pressure of the tire is detected by an air pressure sensor (not shown) attached to the inside of the tire or wheel. The tire air pressure acquisition unit 11 may acquire the air pressure from a tire pressure monitoring system (TPMS) that monitors the tire air pressure and senses an abnormality.

  The steering steering number acquisition unit 12 acquires a detected value (steering angle of the steering wheel) of a steering sensor (not shown). The steering steering number acquisition unit 12 calculates the number of steering operations based on the detected value of the steering sensor.

  The steering speed acquisition unit 13 acquires the detection value of the steering sensor. The steering steering speed acquisition unit 13 calculates the steering steering speed based on the detection value of the steering sensor.

  The vehicle lateral G acquisition unit 14 acquires a detection value of a lateral acceleration sensor (not shown). The vehicle lateral G acquisition unit 14 calculates the lateral G of the vehicle every predetermined time based on the detection value of the lateral acceleration sensor.

  The vehicle deceleration acquisition unit 15 acquires a detection value of a front / rear G sensor (not shown). The vehicle deceleration acquisition unit 15 calculates the vehicle deceleration every predetermined time based on the detection values of the front and rear G sensors.

  The engine torque output value acquisition unit 16 acquires a detection value of a torque sensor (not shown). The engine torque output value acquisition unit 16 calculates an output value of the engine torque every predetermined time based on the detection value of the torque sensor.

  The tire air pressure, the number of steering operations, the steering speed, the vehicle lateral G, the vehicle deceleration, and the output value of the engine torque may be collectively referred to as “information on how the tire is used”. In addition, information on how tires are used may be simply referred to as “related information”.

  The calculation unit 20 includes components of a groove depth calculation unit 21, a groove depth estimation unit 22, and a travel distance calculation unit 23. The function of each component of the calculation part 20 is implement | achieved when ECU10 runs a control program.

  The groove depth calculation unit 21 calculates a wear amount for each tire at predetermined time intervals with reference to a predetermined calculation formula based on information (related information) on how the tire is used, such as tire air pressure. To do. In addition, a calculation formula is represented as the sum total of the amount of wear by each of related information, for example. The calculation formula is set according to, for example, the type of tire and the vehicle type. The amount of wear for each tire is stored in the storage unit 30 in association with the travel distance corresponding to the time when the related information is acquired and the time when the related information is acquired. The travel distance is calculated by the ECU 10 based on the detection result of the vehicle speed sensor (not shown).

  The groove depth calculation unit 21 calculates the groove depth of the tire for each predetermined travel distance (for example, 100 km) based on the above-described wear amount. Here, the groove depth calculation unit 21 calculates an average groove depth in the entire region in the tire width direction. The groove depth calculation unit 21 may calculate the groove depth for each predetermined travel distance, for example. When the travel distance reaches 500 km, for example, the groove depth calculation unit 21 summarizes the tire groove depth every 100 km. May be calculated.

  FIG. 2 is a graph showing the relationship between the travel distance and the tire groove depth. FIG. 2 shows coordinates in which the travel distance is on the horizontal axis and the tire groove depth is on the vertical axis. On the coordinates of FIG. 2, the groove depth of the tire for each travel distance is plotted and shown limited to the tires of the left rear wheel and the right front wheel of the four wheels.

  The groove depth estimation unit 22 estimates a change in the groove depth of the tire with respect to the travel distance. The groove depth estimation unit 22 specifically uses a known method (for example, the least square method) to determine the tire groove depth for each travel distance (five groove depths plotted in FIG. 2). Find an approximate line that approximates. The obtained approximate straight line represents a change in the groove depth of the tire with respect to the travel distance.

  The travel distance calculation unit 23 calculates the remaining travel distance until the difference in groove depth between tires exceeds an allowable value based on the obtained approximate straight line.

  Hereinafter, a method for calculating the remaining travel distance will be described in detail with reference to FIG. Here, it is assumed that the difference in groove depth between the tires of the left rear wheel and the right front wheel of the four wheels expands the fastest, and the calculation method will be described by limiting to these two tires. FIG. 2 shows an approximate straight line LL representing a change in the groove depth of the tire of the left rear wheel with respect to the travel distance. In addition, an approximate straight line LR representing a change in the groove depth of the tire of the right front wheel with respect to the travel distance is shown.

  The travel distance calculation unit 23 obtains the remaining travel distance DT from the current position CP until the difference in groove depth exceeds the allowable value Va in the two approximate straight lines LL and LR.

  The storage unit 30 stores a control program for executing the function of each component of the calculation unit 20.

  The output unit 40 outputs the result calculated by the calculation unit 20 (for example, the remaining travel distance DT).

  The ECU 10 causes the notification unit 50 to display the remaining travel distance DT. When displaying the remaining travel distance DT, the ECU 10 may display that the difference between the tire groove depth of the left rear wheel and the tire groove depth of the right front wheel reaches the allowable value Va.

  Next, the tire rotation support process will be described with reference to FIG. FIG. 3 is a flowchart showing the tire rotation support process. This process is started, for example, when the vehicle is turned on.

  First, in step S100, the input unit 100 acquires information regarding how the tire is used.

  In step S110, the groove depth calculation unit 21 calculates the groove depth of the tire for each travel distance based on information on how the tire is used.

  In step S120, the groove depth estimation unit 22 estimates a change in the tire groove depth with respect to the travel distance based on the tire groove depth for each travel distance.

  In step S <b> 130, the travel distance calculation unit 23 calculates the remaining travel distance until the difference in groove depth between tires exceeds the allowable value.

  In step S140, the ECU 10 causes the notification unit 50 to display the remaining travel distance. Thereafter, the process ends.

<Effects of the present embodiment>
As described above, the control device 1 according to the present embodiment calculates the groove depth of each of the plurality of tires based on the information on how to use the plurality of tires mounted on the vehicle. 21, a groove depth estimation unit 22 that estimates, for each tire, a change in the groove depth with respect to the travel distance from the calculated groove depth, and a plurality of tires based on the change in the groove depth with respect to the travel distance for each tire. And a travel distance calculation unit 23 that calculates a remaining travel distance until the difference in groove depth exceeds a predetermined allowable value. This makes it possible to accurately notify the user or the like of the remaining travel distance that serves as a guide for the tire rotation time, so that the tire rotation can be performed appropriately.

  In the control device 1 according to the above-described embodiment, the input unit 100 includes a tire air pressure acquisition unit 11 that acquires tire air pressure. However, the present invention is not limited to this. For example, the input unit 100 may include an acquisition unit that acquires vehicle speed, vehicle acceleration, and axle load in addition to them. The groove depth calculation unit 21 calculates the groove depth of the tire based on information on how these tires are used. As a result, the calculated groove depth can be made closer to the actual groove depth of the tire, so the remaining travel distance can be accurately notified by the user or the like.

  Moreover, in the said embodiment, when calculating the groove depth of a tire, the groove depth calculation part 21 calculates the average groove depth in a tire width direction all area | region. However, the present invention is not limited to this. When the entire tire width direction region is divided into a plurality of regions (for example, an inner region in the tire width direction, an outer region in the tire width direction, and a central region in the tire width direction), the groove depth calculation unit 21 The groove depth in the region may be calculated. Thereby, the traveling distance calculation part 23 can calculate the remaining traveling distance until the difference of the groove depth in the outer region in the tire width direction between the tires exceeds the allowable value. For this reason, by performing tire rotation based on the remaining travel distance, for example, it is possible to suppress the tire from being partially reduced in a vehicle in which uneven wear (outside reduction) in the outer region in the tire width direction tends to be severe.

  The control device of the present disclosure is useful as a driving support device that is required to support the vehicle so that it can travel safely through various information related to the condition of the tire.

1 control device 10 ECU
DESCRIPTION OF SYMBOLS 11 Tire air pressure acquisition part 12 Steering steering frequency acquisition part 13 Steering steering speed acquisition part 14 Vehicle side G acquisition part 15 Vehicle deceleration acquisition part 16 Engine torque output value acquisition part 20 Calculation part 21 Groove depth calculation part 22 Groove depth estimation Unit 23 travel distance calculation unit 30 storage unit 40 output unit 50 notification unit 100 input unit

Claims (3)

An input unit for inputting information on how to use a plurality of tires mounted on the vehicle;
Based on information on how to use the tire, a calculation unit that calculates a remaining travel distance until a difference in groove depth between the plurality of tires exceeds a predetermined allowable value;
A control device comprising: The calculation unit includes:
Based on information on how the tire is used, a groove depth calculation unit that calculates the groove depth of each of the plurality of tires, and
A groove depth estimation unit that estimates a change in the groove depth with respect to a travel distance from the calculated groove depth for each tire;
A travel distance calculating unit that calculates a remaining travel distance until a difference in groove depth between the plurality of tires exceeds a predetermined allowable value based on a change in groove depth with respect to the travel distance for each tire; ,
The control device according to claim 1, comprising:   The information on how the tire is used includes at least one of tire air pressure, steering frequency, steering speed, axle load, vehicle speed, vehicle acceleration, vehicle deceleration, engine torque output value, and vehicle lateral G. The control device according to claim 1, comprising:

Images