Ballpoint pen point and ballpoint pen

Abstract

The invention provides a ballpoint pen point smooth in writing hand feeling and a ballpoint pen. A pen point main body 2 of the ballpoint pen point 1 comprises: a pen bead holding chamber 50, whereinan abutting surface 53a is formed on the rear end wall of the pen bead holding chamber 50; a rear end hole 40 provided so as to extend from the rear end side toward the front end side; and an ink guide hole 60 formed in the center of the abutting surface 53a to make the rear end hole 40 communicate with the pen bead holding chamber 50 so that an angle between a straight line extending from the center of the ball 3 to the thinnest part A in a state of abutting the abutting surface 53a and the center line of the ballpoint pen point 1 is 35-55 degrees, the distance between the outer peripheral surface of the pen point main body 2 of the thinnest part A and the inner wall of the rear end hole 40 is the shortest, and the distance between the upper end edge of the rear end wall and the thinnestpart A in the direction of the center line of the pen point main body 2 is 90% or less of the diameter of the pen bead.

Description

technical field [0001] The invention relates to a ball-point pen nib and a ball-point pen comprising the ball-point pen nib. Background technique [0002] The nib of the ballpoint pen includes a nib main body, and the nib main body has: a ball-holding room for holding a pen ball; an ink guide hole formed on the rear end wall of the ball-holding room the center; and, a plurality of ink guide grooves radially extending from the ink guide holes. The top part of the pen ball holding chamber is retracted inwardly, so that a part of the pen ball protrudes from the top edge of the pen point, and holds the pen ball in a freely rotating manner. [0003] Here, the shape of the abutting surface located on the rear end wall of the ball holding chamber is important for writing comfort, and studies on the shape of the abutting surface are also being carried out. For example, Patent Document 1 attempts to improve the writing feel by providing a curved abutment surface with a curvature di...

AI Technical Summary

Problems solved by technology

[0004] However, according to Patent Document 1, the contact state between the abutting surface at the rear end wall of the ball holding chamber and the ball is not uniform.

In this case, the coefficient of friction between the pen ball and the abutment surface increases, and the writing feel is limited.

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