Micro motion poppet valve assembly for delivery of ink with large pigment particles to a writing nib and writing instrument comprising same

A writing instrument for use with inks comprising large pigment particles, the writing instrument comprising:

• an instrument body;
• an ink reservoir disposed within the instrument body;
• a valve assembly disposed within the instrument body, the valve assembly including a writing nib;
• a valve body coupled to a biasing element, a shoulder formed within a central bore of the valve body, a valve stem partially disposed within the valve body, an angled rib extending outwardly from a periphery of the valve stem and axially along the valve stem, and a valve plug coupled to the valve stem,
• wherein the writing nib is coupled to the valve stem, the writing nib and valve stem being longitudinally movable with respect to the valve body and biasing element,
• wherein the biasing element includes a body and a cone-shaped portion, the cone-shaped portion being deformable along a longitudinal axis, and the cone-shaped portion biasing the valve stem to a closed position, and
• wherein an ink channel fluidly connects the ink reservoir, the valve plug, the biasing element, the valve stem, and the writing nib for delivery of ink from the ink reservoir to the writing nib.

A micro-motion poppet valve assembly for a writing instrument, the poppet valve assembly comprising:

• a writing nib;
• a valve body coupled to a biasing element,
• a valve stem partially disposed within the valve body,
• a valve plug coupled to the valve stem,
• an annular channel on an outer surface of the valve body that is sized to receive an annular seal, and
• an annular seal disposed in the annular channel,
• wherein the writing nib is coupled to the valve stem, the writing nib and the valve stem being longitudinally movable with respect to the valve body and the biasing element, wherein the biasing element includes a body and a cone-shaped portion, the cone-shaped portion being deformable along a longitudinal axis, wherein the cone-shaped portion biases the valve stem to a closed position, and wherein the annular seal is integrally formed with the biasing element.