US 5,829,904 AGranted

Writing implement ink conducting core

AssigneeMitsubishi Pencil Company, Limited

InventorsKazuaki Matsumoto, Motohiro Komiya, Jun Hosoya

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Abstract

An ink conducting core for supplying ink from an ink container to a pen point is formed with an exposing recess in the vicinity of a connecting portion of the ink conducting core with a middle core. With this, even when outside impact etc. causes air bubbles to enter the ink conducting core, the bubbles may be ejected readily through the exposing recess whereby smooth ink supply can be secured all the time. An annular groove and a small diameter portion is provided in the rear part of an ink conducting core. An ink retainer having a through-hole through which the ink conducting core is fitted is constructed such that the through-hole has a small diameter portion in the rear end thereof. The ink conducting core is fitted to the ink retainer with the side walls of the annular groove engaging the small diameter portion in the rear end of the through-hole. As a result, it is possible to securely restrict back-and-forth movement of the ink conducting core due to impact etc.

Claims11

Dependent claims

A writing implement comprising:

a barrel cylinder having an ink container for directly storing ink in the rear part thereof;
an ink retainer attached in the front part of said barrel cylinder and having a through-hole provided substantially coaxially in the center thereof, a plurality of circular grooves on the outer periphery thereof for retaining ink and a longitudinal flute communicating between said circular grooves;
a middle core composed of a bundle of fibers and connected to the rear part of a pen point;
and
an ink conducting core fitted to said through-hole of said ink retainer and having an ink flow passage longitudinally extending thereinside and which communicates the rear part of said middle core with said ink container, so that ink is conducted through said ink flow passage from said ink container to said middle core;
wherein:
said ink conducting core is further formed with an exposing recess for exposing said ink flow passage to the outside of said ink conducting core in the vicinity of the connecting portion of said ink conducting core with said middle core so that air bubbles within said ink flow passage are ejectable to the outside of said ink flow passage;
and
said ink flow passage is an internal passage contained within said ink conducting core and is only exposed to the outside at said exposing recess.

6 more elements

A writing implement comprising:

a barrel cylinder having an ink container for directly storing ink in the rear part thereof;
an ink retainer attached in the front part of said barrel cylinder and having a through-hole provided substantially coaxially in the center thereof, a plurality of circular grooves on the outer periphery thereof for retaining ink and a longitudinal flute communicating between said circular grooves;
a middle core composed of a bundle of fibers and connected to the rear part of a pen point;
and
an ink conducting core fitted to said through-hole of said ink retainer and having an ink flow passage longitudinally extending thereinside and which communicates the rear part of said middle core with said ink container, so that ink is conducted through said ink flow passage from said ink container to said middle core;
wherein:
the rear end of said through-hole of said ink retainer is formed with a small diameter portion and the rear part of said ink conducting core is formed with an annular groove and a small diameter portion, said small diameter portion of said ink conducting core being positioned within said small diameter portion of said ink retainer so that when a front side wall defining said annular groove abuts a stepped portion defined by said small diameter portion of said through-hole of said ink retainer, backward movement of said ink conducting core is restricted, while when a rear side wall defining said annular groove abuts the rear face of said small diameter portion of said through-hole, forward movement of said ink conducting core is restricted.

4 more elements

A writing implement comprising:

a barrel cylinder having an ink container for directly storing ink in the rear part thereof;
an ink retainer attached in the front part of said barrel cylinder and having a through-hole provided substantially coaxially in the center thereof, a plurality of circular grooves on the outer periphery thereof for retaining ink and a longitudinal flute communicating between said circular grooves;
a middle core composed of a bundle of fibers and connected to the rear part of a pen point;
and
an ink conducting core fitted to said through-hole of said ink retainer and having an ink flow passage longitudinally extending thereinside and which communicates the rear part of said middle core with said ink container, so that ink is conducted through said ink flow passage from said ink container to said middle core;
wherein:
said ink conducting core is formed with an exposing recess for exposing said ink flow passage to the outside of said ink conducting core in the vicinity of the connecting portion of said ink conducting core with said middle core so that air bubbles within said ink flow passage are ejectable to the outside said ink flow passage;
said ink flow passage is an internal passage contained within said ink conducting core and is only exposed to the outside at said exposing recess;
and the rear end of said through-hole of said ink retainer is formed with a small diameter portion and the rear part of said ink conducting core is formed with an annular groove and a small diameter portion, said small diameter portion of said ink conducting core being positioned within said small diameter portion of said ink retainer so that when a front side wall defining said annular groove abuts a stepped portion defined by said small diameter portion of said through-hole of said ink retainer, backward movement of said ink conducting core is restricted, while when a rear side wall defining said annular groove abuts the rear face of said small diameter portion of said through-hole, forward movement of said ink conducting core is restricted.

6 more elements

Dependencies are inferred from the claim text.