Writing instrument
AssigneeTeibow Company Limited
InventorKatsumi Otsuka
Life of this patent
Estimating the term…
Abstract
An improved writing nib for a writing instrument comprising a casing and an ink reservoir in the casing. The nib comprises an outer cylindrical wall and equiangularly spaced inner partitions which are formed integral with the wall in cantilever fashion. Each inner partition has a transverse cross section which is comprised of a plurality of partially intersected circles of different diameter.
Claims11
In a writing instrument comprising a cylindrical casing having a rear end and a forward end, an ink reservoir in said casing, and a writing nib having a rear end in said ink reservoir and a forward end projecting from the forward end of said casing, said nib having a tapered tip portion extending forwardly from said forward end of the casing, the improvement wherein said nib comprises an outer wall of cylindrical shape and a plurality of inner partitions formed integral with said outer wall in cantilever fashion, each said inner partition having a transverse cross-section which is comprised of a plurality of partially intersected circles of different diameter aligned radially in such a manner that the intersected circles of larger diameter and of smaller diameter are arranged alternately, each intersected circle of each inner partition being spaced circumferentially on a concentric circle coaxial with said outer cylindrical wall from the corresponding intersected circle having the same diameter of the neighboring inner partition, so that an inner capillary conduit for ink comprised of a plurality of capillary passages of various transverse dimensions is defined between said outer cylindrical wall and said inner partitions, one end of said inner capillary conduit for the ink terminating at said tapered tip portion of the nib and the other end terminating at said rear end of the nib, whereby said ink contained in said ink reservoir is introduced from said reservoir to said inner capillary conduit and can flow to said tip portion through said capillary passages of various dimensions, so that the ink flows smoothly and continuously to said tip through the capillary conduit upon the consumption of ink due to the use of said writing instrument.
In a writing instrument comprising a cylindrical casing (10) having a rear end and a forward end, an ink reservoir (16) in said casing (10), and a writing nib (20) having a rear end (20b) in said ink reservoir (16) and a forward end (20a) projecting from the forward end of said casing (10), said nib (20) having a tapered tip portion (20a) extending forwardly from said forward end of the casing (10),
- wherein the improvement comprises said nib (20) having:
- an outer wall (22) of cylindrical shape and a plurality of inner partitions (32, 32, 34) formed integral with said outer wall (22) in cantilever fashion;
- each said inner partition (30, 32, 34) having a transverse cross-section which is comprised of a plurality of partially intersected circles of different diameter aligned radially;
- each intersected circle of each inner partition (30, 32, 34) being spaced circumferentially on a concentric circle coaxial with said outer cylindrical wall (22) from the corresponding intersected circle having the same diameter of the neighboring inner partition, so that an inner capillary conduit for ink comprised of a plurality of radial capillary passages (36) of substantially varying width along a radial direction is defined between said outer cylindrical wall (22) and said inner partition (30, 32, 34);
- each intersected circle of each partition and the corresponding intersected circle of the neighboring partition defining a constricted capillary passage zone;
- and
- two adjacent intersected circles of each partition and the corresponding two intersected circles of the neighboring partition defining an enlarged capillary passage zone.
A writing instrument, comprising:
- a casing;
- an ink reservoir in said casing;
- a writing nib having a first end extending to said ink reservoir, and having a second end extending out of said casing;
- said nib includes an outer wall and inner partitions secured to said outer wall in cantilever fashion;
- each said inner partition has a transverse cross-section formed completely by intersecting circles;
- an inner capillary passage zone formed by the continuous and contiguous space disposed between said inner partitions;
- an outer capillary passage zone surrounding but separated from said inner capillary passage zone;
- and
- said outer capillary passage zone comprising a plurality of separate, distinct and disconnected outer capillary conduits (28) formed in said outer wall of said writing nib.
Dependencies are inferred from the claim text.