Dynamic sweep angle measurement for fault monitoring of windshield wiper systems

Patent metadata

Field	Value
Publication number	US-2021046902-A1
Application number	US-201916690936-A
Country	US
Kind code	A1
Filing date	Nov 21, 2019
Priority date	Aug 14, 2019
Publication date	Feb 18, 2021
Grant date	—

Abstract

A windshield wiper system (WWS) is provided and includes a wiper blade assembly drivable along a first sweep angle, an internal wiper trigger disposed to move with the wiper blade assembly, a measurement system configured to monitor a position of the internal wiper trigger from which a corresponding position of the wiper blade assembly relative to the first sweep angle is measurable and to output a sweep angle feedback signal corresponding to monitoring results and a controller. The controller is receptive of the sweep angle feedback signal.

First claim

What is claimed is:

1 . A windshield wiper system (WWS), comprising:
a wiper blade assembly drivable along a first sweep angle; an internal wiper trigger disposed to move with the wiper blade assembly; a measurement system configured to monitor a position of the internal wiper trigger from which a corresponding position of the wiper blade assembly relative to the first sweep angle is measurable and to output a sweep angle feedback signal corresponding to monitoring results; and a controller receptive of the sweep angle feedback signal.

2 . The WWS according to claim 1 , wherein the controller is configured to control a driving of the wiper blade assembly in accordance with the sweep angle feedback signal.

3 . The WWS according to claim 1 , wherein the wiper blade assembly is configured to move across a windshield of a vehicle and comprises a wiper arm and a wiper blade attached to the wiper arm.

4 . The WWS according to claim 1 , further comprising:
a motor, which is operable by a motor drive control signal output from the controller; and a mechanical gear train and four bar linkage operably interposed between the motor and the wiper blade assembly, wherein the controller is configured to control the driving of the wiper blade assembly in accordance with the sweep angle feedback signal and in accordance with position, current and temperature feedback signals derived from the motor.

5 . The WWS according to claim 1 , wherein the internal wiper trigger is coupled to the wiper blade assembly.

6 . The WWS according to claim 1 , wherein:
the internal wiper trigger generates a magnetic field, and the measurement system is responsive to the magnetic field to monitor the position of the internal wiper trigger.

7 . The WWS according to claim 6 , wherein:
the measurement system comprises Hall Effect sensors positioned proximate to opposite ends of the second sweep angle, the Hall Effect sensors being configured to generate a variable duty cycle output responsive to the magnetic field and to issue the variable duty cycle output to the controller as the sweep angle feedback signal.

8 . A windshield wiper system (WWS), comprising:
a wiper blade assembly drivable along a first sweep angle; an internal wiper trigger disposed to move with the wiper blade assembly and along a second sweep angle corresponding to the first sweep angle; a measurement system configured to monitor a position of the internal wiper trigger relative to the second sweep angle from which a corresponding position of the wiper blade assembly relative to the first sweep angle is measurable and to output a sweep angle feedback signal corresponding to monitoring results; and a controller receptive of the sweep angle feedback signal.

9 . The WWS according to claim 8 , wherein the controller is configured to control a driving of the wiper blade assembly in accordance with at least the sweep angle feedback signal.

10 . The WWS according to claim 8 , wherein the wiper blade assembly is configured to move across a windshield of a vehicle and comprises a wiper arm and a wiper blade attached to the wiper arm.

11 . The WWS according to claim 8 , wherein the second sweep angle is a same sweep angle as the first sweep angle.

12 . The WWS according to claim 8 , further comprising:
a motor, which is operable by a motor drive control signal output from the controller; and a mechanical gear train and four bar linkage operably interposed between the motor and the wiper blade assembly, wherein the controller is configured to control the driving of the wiper blade assembly in accordance with the sweep angle feedback signal and in accordance with position, current and temperature feedback signals derived from the motor.

13 . The WWS according to claim 8 , wherein the internal wiper trigger is coupled to the wiper blade assembly.

14 . The WWS according to claim 8 , wherein:
the internal wiper trigger generates a magnetic field, and the measurement system is responsive to the magnetic field to monitor the position of the internal wiper trigger relative to the second sweep angle.

15 . The WWS according to claim 14 , wherein:
the measurement system comprises Hall Effect sensors positioned proximate to opposite ends of the second sweep angle, the Hall Effect sensors being configured to generate a variable duty cycle output responsive to the magnetic field and to issue the variable duty cycle output to the controller as the sweep angle feedback signal.

16 . A method of operating a windshield wiper system (WWS), the method comprising:
driving a wiper blade assembly along a first sweep angle by a controller; monitoring a position of an internal wiper trigger disposed to move with the wiper blade assembly from which a corresponding position of the wiper blade assembly relative to the first sweep angle is measurable; outputting a sweep angle feedback signal corresponding to results of the monitoring to the controller; and controlling the driving of the wiper blade assembly by the controller in accordance with at least the sweep angle feedback signal.

17 . The method according to claim 16 , wherein the controlling of the driving of the wiper blade assembly by the controller is executed in accordance with the sweep angle feedback signal and in accordance with motor position, motor current and motor temperature feedback signals.

18 . The method according to claim 1 wherein the monitoring comprises:
generating a magnetic field at an internal wiper trigger disposed to move with the wiper blade assembly: and
generating a variable duty cycle output responsive to the magnetic field for issuance to the controller as the sweep angle feedback signal.

19 . The method according to claim 16 , wherein the sweep angle feedback signal has a negligible parallax error.

20 . The method according to claim 16 , further comprising at least one of:
in-flight gear and shaft and real-time sweep angle monitoring based on the sweep angle feedback signal; computing a speed of a motor configured to drive the wiper blade assembly; and facilitating an identification of ageing issues or failures of the motor, the wiper blade assembly or a gear train interposed between the motor and the wiper blade assembly.

Assignees

• Rosemount Aerospace Inc

Inventors

• Manjunath Aruna
• Mothe Venkata Anil Kumar
• Vadgaonkar Prashant

Classifications

• B60S1/08 Primary

  electrically driven {(conjoint control of windscreen wiper motor and liquid supply of windscreen washer B60S1/482; conjoint control of windscreen wiper motor and means for cleaning parts o parts other than windscreens or front windows B60S1/56, B60S1/58, B60S1/606)} · CPC title

• B60S1/3409 Primary

  the wiper arms consisting of two or more articulated elements · CPC title

• B60S1/26

  by toothed gearing · CPC title