Ball-point pen

A ball-point pen comprising:

• a barrel cylinder for holding a ball-point pen refill;
• and
• a ball-point pen refill accommodated in said barrel cylinder and comprising:
• a tip having a front opening, a tip ball, a rear end having a rearmost press-bent portion, and a spring urging said tip ball into intimate contact with the inside edge of a ball holding portion at the front end of said tip to close said front opening, said holding portion further including a plurality of ink flowing channels defined therein adjacent the end of said tip ball being urged by said spring;
• an ink reservoir which stores low-viscosity oily ink having excellent resistance to dryness and has an ink follower provided in the rear end of said ink reservoir;
• and
• a joint disposed between said tip and said ink reservoir and having an inside hollow, said joint comprising:
• a ball valve;
• a valve chamber loosely holding said ball valve therein, and communicating with said rear end of said tip;
• a ball valve seat disposed on the rear side of said valve chamber;
• and a conduit disposed in the rear side of said ball valve seat and providing communication between said valve chamber and said ink reservoir;
• wherein:
• said ball valve alternately rests on said press-bent portion of said tip to allow ink to flow to said tip and on said ball valve seat to hermetically seal said valve chamber in order to prevent backward flow of ink;
• and
• at the time of writing, said tip ball is pressed inward against the resiliency of said spring m release the intimately contacting state between said tip ball and said ball holding portion and thereby allow ink to flow through said ink flowing channels and out said front opening.

A ball-point pen comprising:

• a barrel cylinder for holding a ball-point pen refill;
• and
• a ball-point pen refill accommodated in said barrel cylinder and comprising:
• a hollow tip having a front opening, a spring, a tip ball held in a holding portion at the from end of said tip by said spring, and a rear end through which a rear portion of said spring extends, said holding portion further including a plurality of flowing channels defined therein adjacent the end of said tip ball being urged by said spring;
• an ink reservoir which stores low-viscosity oily ink having excellent resistance to dryness and has an ink follower provided in the rear end of said ink reservoir;
• and
• a joint disposed between said tip and said ink reservoir and having an inside hollow, said joint comprising:
• a ball valve;
• a valve chamber loosely holding said ball valve therein and communicating with said rear end of said tip, said valve chamber having a plurality of resiliently deformable inwardly-projecting ribs at a front side of said valve chamber adjacent said rear end of said tip, said rear portion of said spring abutting said ribs;
• a ball valve seat disposed on the rear side of said valve chamber;
• and a conduit disposed in the rear side of said ball valve seat and providing communication between said valve chamber and said ink reservoir;
• wherein:
• said ball valve alternately rests on said projecting ribs to allow ink to flow to said tip and on said ball valve seat to hermetically seal said valve chamber in order to prevent backward flow of ink;
• and
• at the time of writing, said tip ball is pressed inward against the resiliency of said spring to release the intimately contacting state between said tip ball and said ball holding portion and thereby allow ink to flow through said ink flowing channels and out said front opening of said tip.