초록 ▼

A rotationally adjustable respirator cartridge having a self-contained end of service life indicator adjacent the interior of a sidewall of the cartridge shell and in contact with the filter medium provides a color-changing display field that is visible to the wearer of the respirator through a tran

A rotationally adjustable respirator cartridge having a self-contained end of service life indicator adjacent the interior of a sidewall of the cartridge shell and in contact with the filter medium provides a color-changing display field that is visible to the wearer of the respirator through a transparent portion of the sidewall. A display window is defined by an opaque border area that surrounds the sensor display field and obscures a predetermined portion of the downstream end of the indicator to provide a desired margin of safety to the wearer. In order to permit the wearer to rotationally position the color-changing display field in the line of sight through the transparent portion of the respirator facepiece, the cartridge is provided with a rotatable mounting assembly that is continuously rotatable in one direction and that forms a seal with the cartridge shell.

대표청구항 ▼

1. A respirator cartridge comprising:a cartridge shell having a sidewall, at least a portion of which sidewall is transparent; a chemical sensor having a color-changing display field, the sensor being securely positioned proximate an interior surface of a transparent portion of the cartridge sidewal

1. A respirator cartridge comprising:a cartridge shell having a sidewall, at least a portion of which sidewall is transparent; a chemical sensor having a color-changing display field, the sensor being securely positioned proximate an interior surface of a transparent portion of the cartridge sidewall, said display field having an upstream end and a downstream end; a display window defined by an opaque border positioned on the transparent portion of the cartridge sidewall, the display window being at least partially aligned with the display field of the sensor, the downstream end of the display field of the sensor extending to the downstream end of the display window formed by the opaque border; a chemical sorbent material contained by said cartridge shell and in touching contact with said sensor; said cartridge further comprising: an outwardly extending mounting collar joined to the cartridge shell, said mounting collar including seal-forming means, a threaded flange member having pawl and seal-forming means received in mating relation with said mounting collar, ratchet means formed in a surface of the cartridge shell to operatively engage the pawl means in the flange member, where said seal-forming means comprise an annular ring and a corresponding annular seat, whereby said flange member is securely joined to said cartridge shell in fluid-tight rotatable relation.