摘要 |
A welding helmet includes a shutter assembly with an electronically controlled liquid crystal shutter in a compact housing for physical mounting near the face area of a protective shell. The electronic controls provide for the customary auto-darkening function as well as two user selectable fixed shade settings which permit the user to fix the shutter shade in one of a plurality of preselected and factory set shade settings. When fixed at a shade setting, the user is given a visual indication that the helmet is not in an auto-darkening mode. The housing allows for two PC boards to be mounted above and below the optical shutter, with a flexible cable interconnecting the two PC boards so as to not interfere with or obscure the user's vision. The controls are all single function, readily accessible and continuous so that multiple operation of any one control does not switch the associated function off, allowing a user to continuously operate any control repeatedly to ensure its selection. As the electronics and shutter are self contained in a single housing, ready assembly and field change out are accommodated. |