Tire pressure monitoring system of motor driven vehicle and method thereof

Patent metadata

Field	Value
Publication number	US-9387735-B2
Application number	US-201414546917-A
Country	US
Kind code	B2
Filing date	Nov 18, 2014
Priority date	Jun 2, 2014
Publication date	Jul 12, 2016
Grant date	Jul 12, 2016

Abstract

A tire pressure monitoring system includes a resolver for detecting a motor speed generating driving torque. A wheel speed sensor detects a wheel speed of wheels rotated by the driving torque generated at the motor. A transmission decelerates the driving torque generated at the motor. A controller is configured to compare a first target wheel speed calculated using the motor speed detected by the resolver to the wheel speed sensor detected by the wheel speed sensor and determining a status of a tire, when a wheel slip ratio is less than a predetermined value.

First claim

What is claimed is:

1. A tire pressure monitoring system of a motor driven vehicle, the system comprising:
a resolver for detecting a speed of a motor which generates a driving torque;
a wheel speed sensor for detecting a wheel speed of wheels which rotate by the driving torque generated by the motor;
a transmission for decelerating the driving torque generated at the motor; and
a controller configured to compare a first target wheel speed calculated using the motor speed detected by the resolver with the wheel speed detected by the wheel speed sensor and configured to determine a status of a tire, when a wheel slip ratio is less than a predetermined value,
wherein the controller calculates the first target wheel speed by using the motor speed detected by the resolver, a wheel radius, and a gear ratio of the transmission corresponding to a shift speed.

2. The tire pressure monitoring system of claim 1 ,
wherein the first target wheel speed T 1 is calculated from the following equation:

T
⁢

⁢
1

=

w
m

×

1
n

×

2
·
π
·

R
w

60

,

wherein Wm is the motor speed detected by the resolver, Rw is the wheel radius, and n is the gear ratio of the transmission.

3. The tire pressure monitoring system of claim 1 ,
wherein the controller calculates a second target wheel speed by multiplying the first target wheel speed by a correcting coefficient considering a load condition of the vehicle and a road condition, and
determines the status of the tire by comparing the second target wheel speed to the wheel speed detected by the wheel speed sensor.

4. The tire pressure monitoring system of claim 3 ,
wherein the correcting coefficient is determined by a first correcting coefficient considering a throttle opening and a throttle opening variation, a second correcting coefficient considering a vehicle speed and a longitudinal direction acceleration, and a third correcting coefficient considering a vehicle load, and
the first correcting coefficient to the third correcting coefficient are predetermined mapping data and are saved to the controller.

5. The tire pressure monitoring system of claim 3 ,
wherein the controller determines the status of the tire by comparing a final target wheel speed while correcting the second target wheel speed by considering cornering of the vehicle to the wheel speed detected by the wheel speed sensor,
wherein the final target wheel speed is calculated from the following equations in which a front outer wheel speed Vfo, a front inner wheel speed Vfi, a rear outer wheel speed Vro, and a rear inner wheel speed Vri are the final target wheel speed:

V
fo

=

V
f

·

R
fo

R
f

,

⁢

V
fi

=

V
f

·

R
fi

R
f

,

⁢

V
ro

=

V
r

·

R
r

+

D
/
2

R
r

and

V
ri

=

V
r

·

R
r

-

D
/
2

R
r

,

wherein Vf denotes a vehicle speed, Rf denotes a distance from a cornering center to a front driving shaft, Rfi denotes a distance from a cornering center to a front inner wheel, Rfo denotes a distance from a cornering center to a front outer wheel, Rr denotes a distance from a cornering center to a rear driving shaft, and D denotes a distance between an outer wheel and an inner wheel.

6. The tire pressure monitoring system of a motor driven vehicle of claim 1 ,
wherein the wheel slip ratio (k) is calculated from the following equation:

k
=

v
xf

-

T
r

v
xf

,

wherein Vxf denotes a final vehicle speed, and Tr denotes a real wheel speed detected by the wheel speed sensor.

7. The tire pressure monitoring system of a motor driven vehicle of claim 1 , further comprising an integrated starter and generator (ISG) provided in an engine, the ISG starting the engine or generating an electricity by an

Assignees

• Hyundai Motor Co Ltd

Inventors

• Lee Minsu

Classifications

• B60C23/02

  Signalling devices actuated by tyre pressure {(hand-held tyre pressure gauges G01L17/00)} · CPC title

• B60C23/00 Primary

  Devices for measuring, signalling, controlling, or distributing tyre pressure or temperature, specially adapted for mounting on vehicles; Arrangement of tyre inflating devices on vehicles, e.g. of pumps or of tanks; Tyre cooling arrangements · CPC title

• B60L2240/465

  Slip · CPC title

• B60C23/061 Primary

  by monitoring wheel speed (measuring distance traversed on the ground by vehicles G01C22/00) · CPC title

• B60C23/0488 Primary

  Movement sensor, e.g. for sensing angular speed, acceleration or centripetal force · CPC title