US-12617374-B2 - Adjustable blade load mechanism for cantilever beam wiper arm assembly

Abstract

A windshield wiper system has a drive arm with a drive shaft connector, a curved cantilever beam, and a wiper blade assembly. The drive arm is configured to connect to a drive shaft at the drive shaft connector. The curved cantilever beam is connected to the drive arm with a first drive arm fastener and a moveable drive arm fastener. The first drive arm fastener is positioned on the drive arm between the drive shaft connector and the moveable drive arm fastener. The wiper blade assembly is connected to the curved cantilever beam with a wiper blade fastener. The curved cantilever beam has an effective length extending from the moveable drive arm fastener to the wiper blade assembly fastener.

Inventors

• Vishwanath Hitnalli
• Venkata AnilKumar Mothe
• Phani Srinivas Nouduri

Assignees

• ROSEMOUNT AEROSPACE INC.

Dates

Publication Date

20260505

Application Date

20250110

Priority Date

20240326

Claims (20)

1. 1 . A windshield wiper system comprising: a drive arm having a drive shaft connector, wherein the drive arm is configured to connect to a drive shaft at the drive shaft connector; a curved cantilever beam connected to the drive arm with a first drive arm fastener and a moveable drive arm fastener, wherein the first drive arm fastener is a rivet positioned on the drive arm between the drive shaft connector and the moveable drive arm fastener and wherein the moveable drive arm fastener is positioned at one of a plurality of moveable drive arm fastening positions located on the drive arm such that the moveable drive arm fastener functions as a blade load adjustment feature; and a wiper blade assembly connected to the curved cantilever beam with a wiper blade fastener positioned at a wiper blade assembly fastening position on an outboard tip of the curved cantilever beam; wherein the curved cantilever beam has an effective length extending from the location of the moveable drive arm fastener on the drive arm to the wiper blade assembly fastener such that a blade load exerted by the curved cantilever beam on the wiper blade assembly is a function of the effective length of the curved cantilever beam and the location of the moveable drive arm fastener on the drive arm is selected to provide a selected blade load.
2. 2 . The windshield wiper system of claim 1 , wherein the first drive arm fastener is positioned in a fixed position on the drive arm and the curved cantilever beam.
3. 3 . The windshield wiper system of claim 2 , further comprising a second drive arm fastener to secure the curved cantilever beam to the drive arm.
4. 4 . The windshield wiper system of claim 3 , wherein the second drive arm fastener is a rivet.
5. 5 . The windshield wiper system of claim 1 , wherein the moveable drive arm fastener comprises a nut and bolt.
6. 6 . The windshield wiper system of claim 1 , wherein the plurality of moveable drive arm fastening positions includes a first position, a second position, a third position, and a fourth position, wherein the first position is closest to the first drive arm fastener, the second position is between the first position and the third position, the third position is between the second position and the fourth position, and the fourth position is axially outboard of the first position, the second position, and the third position.
7. 7 . The windshield wiper system of claim 6 , wherein the moveable drive arm fastener is positioned in the first position.
8. 8 . The windshield wiper system of claim 6 , wherein the movable drive arm fastener is positioned in the fourth position.
9. 9 . The windshield wiper system of claim 1 , wherein the movable drive arm fastener is configured to be moved from one of the plurality of moveable drive arm fastening positions to another of the plurality of moveable drive arm fastening positions while the windshield wiper system is installed on a vehicle.
10. 10 . The windshield wiper system of claim 9 , wherein the vehicle is configured for use in terrestrial applications.
11. 11 . The windshield wiper system of claim 9 , wherein the vehicle is configured for use in nautical applications.
12. 12 . The windshield wiper system of claim 9 , wherein the vehicle is configured for use in aerospace applications.
13. 13 . A method of installing a windshield wiper system, comprising: connecting a drive shaft to a drive motor; connecting a drive arm to the drive shaft at a drive shaft connector; connecting a curved cantilever beam to the drive arm with a first drive arm fastener and a moveable drive arm fastener, wherein the first drive arm fastener is a rivet positioned on the drive arm between the drive shaft connector and the moveable drive arm fastener and wherein the moveable drive arm fastener is positioned at one of a plurality of moveable drive arm fastening positions located on the drive arm such that the moveable drive arm fastener functions as a blade load adjustment feature; and connecting a wiper blade assembly to the curved cantilever beam with a wiper blade fastener positioned at a wiper blade assembly fastening position on an outboard tip of the curved cantilever beam; wherein the curved cantilever beam has an effective length extending from the moveable drive arm fastener to the wiper blade assembly fastener such that a blade load exerted by the curved cantilever beam on the wiper blade assembly is a function of the effective length of the curved cantilever beam and the location of the moveable drive arm fastener on the drive arm is selected to provide a selected blade load.
14. 14 . The method of claim 13 , wherein the first drive arm fastener is positioned in a fixed position on the drive arm and the curved cantilever beam.
15. 15 . The method of claim 14 , further comprising a second drive arm fastener to secure the curved cantilever beam to the drive arm.
16. 16 . The windshield wiper system of claim 3 , wherein the second drive arm fastener is a rivet.
17. 17 . The method of claim 13 , wherein the moveable drive arm fastener comprises a nut and bolt.
18. 18 . The method of claim 13 , wherein the plurality of moveable drive arm fastening positions includes a first position, a second position, a third position, and a fourth position, wherein the first position is closest to the first drive arm fastener, the second position is between the first position and the third position, the third position is between the second position and the fourth position, and the fourth position is axially outboard of the first position, the second position, and the third position.
19. 19 . The method of claim 18 , wherein the moveable drive arm fastener is positioned in the first position.
20. 20 . The method of claim 13 , wherein the movable drive arm fastener is configured to be moved from one of the plurality of moveable drive arm fastening positions to another of the plurality of moveable drive arm fastening positions while the windshield wiper system is installed on a vehicle.

Description

CROSS-REFERENCE TO RELATED APPLICATION(S) The aforementioned India Provisional Application No. 202441023932 filed Mar. 26, 2024, are hereby incorporated by reference in their entirety. BACKGROUND The present disclosure relates generally to windshield wiper systems and, more particularly, to windshield wiper systems having an adjustable blade load. As well known, windshield wiper systems (WWS) are used in many applications to clear rain, frozen precipitation, dirt and other debris from windshield. A typical WWS includes a drive motor, drive shaft, drive arm/cantilever beam assembly, wiper blade assembly, and potentially an optional wash system. The blade assembly is held onto the windshield by a force exerted by the arm assembly known as “blade load.” Blade load is an important design parameter that contributes to wipe quality. In a conventional WWS, the blade load exerted by arm assembly on the blade assembly can be adjusted with help of a spring mechanism, Belleville washers, and other designs. SUMMARY One aspect of this disclosure is directed to a windshield wiper system having a drive arm with a drive shaft connector, a curved cantilever beam, and a wiper blade assembly. The drive arm is configured to connect to a drive shaft at the drive shaft connector. The curved cantilever beam is connected to the drive arm with a first drive arm fastener and a moveable drive arm fastener. The first drive arm fastener is positioned on the drive arm between the drive shaft connector and the moveable drive arm fastener. The moveable drive arm fastener is positioned at one of a plurality of moveable drive arm fastening positions. The wiper blade assembly is connected to the curved cantilever beam with a wiper blade fastener positioned at a wiper blade assembly fastening position on an outboard tip of the curved cantilever beam. The curved cantilever beam has an effective length extending from the moveable drive arm fastener to the wiper blade assembly fastener such that a blade load exerted by the curved cantilever beam on the wiper blade assembly is a function of the effective length. Another aspect of this disclosure is directed to a method of installing a windshield wiper system that includes connecting a drive shaft to a drive motor and connecting a drive arm to the drive shaft at a drive shaft connector. A curved cantilever beam is connected to the drive arm with a first drive arm fastener and a moveable drive arm fastener. The first drive arm fastener is positioned on the drive arm between the drive shaft connector and the moveable drive arm fastener. The moveable drive arm fastener is positioned at one of a plurality of moveable drive arm fastening positions. A wiper blade assembly is connected to the curved cantilever beam with a wiper blade fastener positioned at a wiper blade assembly fastening position on an outboard tip of the curved cantilever beam. The curved cantilever beam has an effective length extending from the moveable drive arm fastener to the wiper blade assembly fastener such that a blade load exerted by the curved cantilever beam on the wiper blade assembly is a function of the effective length. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1A is an overhead view of a windshield wiper system of this disclosure. FIG. 1B is an overhead close-up view of the windshield wiper system junction of FIG. 1A. FIG. 1C is a perspective close-up view of the windshield wiper system arm junction of FIG. 1B. FIG. 2 is schematic exploded view of the windshield wiper system arm junction of FIGS. 1A-1C. FIG. 3 is a view of an engraved junction of the cantilever beam of FIG. 2. FIG. 4 is a side view of a windshield wiper system of this disclosure. FIG. 5A is close-up side view of the windshield wiper system junction of FIG. 4. FIG. 5B is another close-up side view of the windshield wiper system junction of FIG. 4. FIG. 6A is a side view of a windshield wiper system of this disclosure. FIG. 6B is another side view of a windshield wiper system of this disclosure. DETAILED DESCRIPTION Windshield wiper systems (WWS) are used in many applications, including terrestrial, nautical, and aerospace applications, to clear rain, frozen precipitation, dirt and other debris from windshields. Terrestrial applications include every type of motor vehicle, rail vehicles, etc. Nautical applications include every type of ship. Aerospace applications include every type of aircraft, including fixed wing and rotary wing aircraft. As discussed above, blade load is an important design parameter that contributes to wipe quality. Some WWS, such as WWS using a cantilever beam wiper arm, do not typically include a contain blade load adjustment feature. Typically, blade load in such arms is only dependent on the cantilever beam design parameters such as the thickness, width, length, material, bend radius etc. of the cantilever beam. Including conventional methods of blade load adjustments (screws for springs, torquing Belleville washers etc.) can incre