Residual braking torque indication devices, systems, and methods

• US 10,451,130 B2
• Filed: 07/24/2017
• Issued: 10/22/2019
• Est. Priority Date: 07/25/2016
• Status: Active Grant

• Current Assignee: ITT Italia SRL (ITT, Inc.)
• Original Assignee: ITT Italia SRL (ITT, Inc.)
• Inventors: Solari, Mattia, Terranova, Marco
• Primary Examiner(s): Nguyen, Xuan Lan
• Application Number:
  US15/658,188
• Publication Number:
  US 20180106319A1
• Time in Patent Office: 820 Days
• CPC Class Codes: B60T 17/22 Devices for monitoring or checking brake systems; Signal devices
• CPC Class Codes: B60T 17/221 Procedure or apparatus for checking or keeping in a correct functioning condition of brake systems hydraulic pressure systems in general F15B19/00, F15B21/04; testing structures or apparatus G01M
• CPC Class Codes: B60T 2201/12 Pre-actuation of braking systems without significant braking effect; Optimizing brake performance by reduction of play between brake pads and brake disc
• CPC Class Codes: F16D 2066/001 Temperature
• CPC Class Codes: F16D 2066/005 Force, torque, stress or strain
• CPC Class Codes: F16D 2066/006 without direct measurement of the quantity monitored, e.g. wear or temperature calculated form force and duration of braking
• CPC Class Codes: F16D 2121/28 using electrostrictive or magnetostrictive elements, e.g. piezoelectric elements
• CPC Class Codes: F16D 65/08 for internally-engaging brakes
• CPC Class Codes: F16D 66/021 using electrical detection or indication means

Abstract

Various residual braking torque indication devices, systems, and methods are described. The devices, systems, and methods can include a sensorized brake pad. An output signal of the sensorized brake pad can be processed to provide an indication of a residual braking torque. The residual braking torque indicator can be calibrated to reference data to provide an actual measurement of the residual braking torque.

Claims

1. A device for detecting the residual braking torque in a vehicle equipped with disk brakes having a friction material, the device comprising:

at least one piezoceramic sensor integrated into a friction material support of a brake assembly, and

an electrical circuit connecting the piezoceramic sensor to at least one electronic control unit, the electronic control unit configured to receive signals detected by said piezoceramic sensor from said brake assembly friction material, wherein a temperature sensor is integrated into the electrical circuit,

wherein the electronic control unit comprises at least one residual braking torque indicator, the residual braking torque indicator configured to interact, via at least one communication interface, with at least one on board computer of the vehicle.

2. The device for detecting the residual braking torque in a vehicle equipped with disk brakes according to claim 1, wherein the residual braking torque indicator enables measurement of residual braking torques in the range of 0.5 Nm to 30 Nm.

3. The device for detecting the residual braking torque in a vehicle equipped with disk brakes according to claim 1, wherein said residual braking torque measurements are from 0.1 Nm to 30 Nm.

4. The device for detecting the residual braking torque in a vehicle equipped with disk brakes according to claim 1, wherein said residual braking torque indicator configured to measure actual braking torque.

5. The device for detecting the residual braking torque in a vehicle equipped with disk brakes according to claim 1, wherein said residual braking torque indicator is configured to measure residual braking torque.

6. The device for detecting the residual braking torque in a vehicle equipped with disk brakes according to claim 1, wherein the electronic control unit is configured to perform an analysis based upon frequency or time.

7. The device for detecting the residual braking torque in a vehicle equipped with disk brakes according to claim 1, wherein the electronic control unit is configured to determine, the residual braking torque based on the frequency spectrum of the signals provided by said at least one piezoceramic sensor.

8. The device for detecting the residual braking torque in a vehicle equipped with disk brakes according to claim 1, wherein the electronic control unit is configured to detect a specific peak structure within the frequency spectrum of the signals provided by said at least one piezoceramic sensor, wherein peaks of the specific peak structure are associated with an angular velocity of rotation of a wheel of said vehicle.

9. The device for detecting the residual braking torque in a vehicle equipped with disk brakes according to claim 1, wherein the electronic control unit is configured to detect a structure of oscillations of the intensity of the signals over time, wherein the oscillations are associated with an angular velocity of rotation of a wheel of said vehicle.

10. The device for detecting the residual braking torque in a vehicle equipped with disk brakes according to claim 1, further comprising:

a hardware or software band-pass filter operating at around 50 Hz.

11. The device for detecting the residual braking torque in a vehicle equipped with disk brakes according to claim 1, wherein said residual braking torque indicator is obtained via signals transmitted by said at least one piezoceramic sensor.

12. The device for detecting the residual braking torque in a vehicle equipped with disk brakes according to claim 1, wherein the electronic control unit further comprises at least one friction material wear indicator.

13. The device for detecting the residual braking torque in a vehicle equipped with disk brakes according to claim 1, wherein a connector is integrated into said friction material support, and the connector is connected to said electrical circuit and the electronic control unit via an electric cable.

14. The device for detecting the residual braking torque in a vehicle equipped with disk brakes according to claim 1, wherein a connector is integrated into said friction material support, and the connector is connected to said electrical circuit by integrating a wireless data transmission module in order to communicate with at least one vehicle on board computer via at least one dedicated communication system.

15. A method for the calibration of the residual braking torque in a vehicle equipped with disk brakes via a calibration reference dynamometer bench, wherein at least one of the disk brakes comprises a brake pad with an embedded sensor, the sensor configured to sense pressures applied to the brake pad and to transmit pad signals indicative of the pressures, the signals being received by an electronic control unit that is configured to determine a residual braking torque indicator, wherein the method comprises:

determining background noise contained within the pad signals;

setting a residual braking torque value by manually adjusting a dynamometer bench;

mutually acquiring residual braking torque data from said dynamometer bench and from the residual braking torque indicator;

determining experimental data, wherein determining the experimental data comprises repeating the manual adjustment and the acquiring residual braking torque data for a plurality of values of said residual braking torque values on said dynamometer bench;

creating an analytical calibration curve based on the experimental data; and

identifying an analytical expression from the calibration curve for converting the residual braking torque indicator values to actual residual braking torque values.

16. A system for determining residual braking torque on the wheel of a motorized vehicle, the system comprising:

a sensorized brake pad comprising;

a support element;

a friction material attached to the support element;

a force sensor positioned between the support element and the friction material, the force sensor configured to transmit signals corresponding to a braking force of the wheel, wherein the force sensor comprises a shear sensor; and

a computing system comprising a processor and a non-transitory storage, the computing system configured to;

receive the signals from the sensorized brake pad;

determine, using the signals from the sensorized brake pad, a residual torque indicator;

adjust, using a calibration curve, the residual torque indicator; and

determine, based on the adjusted residual torque indicator, the residual braking torque on the wheel.

17. The system of claim 16, wherein the computing system is further configured to activate an alarm in response to the residual braking torque on the wheel exceeding a threshold value.

18. The system of claim 16, wherein the computing system comprises an electronic control unit onboard the vehicle.

19. The system of claim 16, wherein the force sensor comprises a piezoceramic sensor.