Automatic darkening filter assembly for a welding protector and a welding protector

Patent metadata

Field	Value
Publication number	US-10952902-B2
Application number	US-201716348576-A
Country	US
Kind code	B2
Filing date	Nov 8, 2017
Priority date	Nov 11, 2016
Publication date	Mar 23, 2021
Grant date	Mar 23, 2021

Abstract

An automatic darkening filter assembly for a welding protector and a welding protector that includes the automatic darkening filter assembly. The automatic darkening filter assembly has a housing that forms an opening in which a switchable light filter is arranged. The switchable light filter is retained by a first and a second resilient gasket that are arranged on opposite sides of the switchable light filter and which each extend circumferentially adjacent a periphery of the switchable light filter. The invention helps maximizing the robustness of the welding protector and facilitates assembly.

First claim

The invention claimed is:

1. An automatic darkening filter assembly for a welding protector, comprising a housing that forms an opening in which a curved switchable light filter is arranged, wherein the curved switchable light filter is contacted and retained by a first and a second resilient gasket that are arranged on opposite sides of the curved switchable light filter and which each extend circumferentially adjacent a periphery of the curved switchable light filter.

2. The automatic darkening filter assembly of claim 1 , wherein the curved switchable light filter is clamped between the first and the second gasket.

3. The automatic darkening filter assembly of claim 1 , wherein the housing comprises a first and a second housing part and wherein the first and the second gasket are arranged between the first and the second housing part.

4. The automatic darkening filter assembly of claim 1 , wherein the first gasket is fixedly attached to the first housing part and wherein the second gasket is fixedly attached to the second housing part.

5. The automatic darkening filter assembly of claim 4 , wherein the attachment between the first and second gasket and the first and the second housing part, respectively, comprises a positive locking and/or material bond.

6. The automatic darkening filter assembly of claim 4 , wherein the attachment between the first and second gasket and the first and the second housing part, respectively, is obtainable by two-component injection molding.

7. The automatic darkening filter assembly of claim 1 , wherein the first and second gasket exhibit a hardness of between 10 shore A and 50 shore A.

8. The automatic darkening filter assembly of claim 1 , wherein the first and second gasket are made of a thermoplastic elastomer.

9. The automatic darkening filter assembly of claim 3 , wherein the first and second housing part in combination form a frame that holds the curved switchable light filter therein by a clamp fit via compression of the first and second gasket.

10. The automatic darkening filter assembly of claim 1 , wherein the first resilient gasket includes a rim that at least partially surrounds the curved switchable light filter.

11. The automatic darkening filter assembly of claim 1 , wherein the curved switchable light filter comprises a liquid crystal cell which has two transparent substrates that each comprise a transparent electrode layer and an alignment layer for the liquid crystal molecules.

12. The automatic darkening filter assembly of claim 11 , wherein the curved switchable light filter further has at least two polarizers that are arranged with their polarization directions oriented angularly offset to each other.

13. The automatic darkening filter assembly of claim 12 , wherein the curved switchable light filter further at least two liquid crystal cells and three polarizers.

14. A welding protector comprising the automatic darkening filter assembly according to claim 1 .

15. The welding protector of claim 14 , wherein the automatic darkening filter assembly is mounted in a welding shield of the welding protector.

16. The automatic darkening filter assembly of claim 10 , wherein the rim cooperates with the second resilient gasket to provide an edge seal for the curved switchable light filter.

17. The automatic darkening filter assembly of claim 1 , wherein the first resilient gasket includes a plurality of circumferential ridges.

Assignees

• 3M Innovative Properties Co

Inventors

• Hansson Johan M P
• Hummel Kjell A
• Stenvall Thomas B
• Bastman Linus P

Classifications

• G02F1/133528

  Polarisers · CPC title

• G02F2202/14

  photochromic · CPC title

• G02F2201/44

  Arrangements combining different electro-active layers, e.g. electrochromic, liquid crystal or electroluminescent layers · CPC title

• G02F1/13

  based on liquid crystals, e.g. single liquid crystal display cells · CPC title

• G02B27/281

  used for attenuating light intensity, e.g. comprising rotatable polarising elements · CPC title