Abstract: A capless retractable sealed marking instrument has a sealed chamber incorporated in a marker casing. The sealed chamber includes a chamber, a wiper ring, and an annular rim and a seal portion with a cross-slit aperture defining surfaces or flaps which are moved out of contact by a linearly-advanced marker nib to open the seal for extension of the marker nib. The configuration of the disk provides positive sealing force between the lateral sealing surfaces of the seal flaps. Retraction of the marker nib draws the flaps back into the sealed chamber configuration to protect the marker nib and cartridge from atmospheric degradation.

Abstract: A capless retractable sealed marking instrument has a sealed chamber incorporated in a marker casing. The sealed chamber includes a chamber, a wiper ring, and an annular rim and a seal portion with a cross-slit aperture defining surfaces or flaps which are moved out of contact by a linearly-advanced marker nib to open the seal for extension of the marker nib. The configuration of the disk provides positive sealing force between the lateral sealing surfaces of the seal flaps. In the storage position, the seal effectively closes to protect and preserve the associated component. In a preferred embodiment, a housing member includes a closing member. The closing member engages the disc to seal the slit in the closed position when the associated component is in storage. The disc may include tabs that engage the closing member.