JP2012081596A - Ballpoint pen tip - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ballpoint pen tip of a simple structure which smoothly supplies ink to a ball.SOLUTION: The ballpoint pen tip includes in a tip body: a ball holding chamber; an ink circulation hole formed in the center of a bottom wall of the ball holding chamber; a rear hole formed behind the ink circulation hole; and a plurality of ink circulation grooves which extend radially from the ink circulation hole and in which the bottom wall does not reach the rear hole. The ballpoint pen tip holds rotatably a part of the ball by projecting it outward from the tip part by: inserting the ball to the bottom wall; and swaging the end of the tip body inside. The ink circulation hole is characterized in that while preparing a front part ink circulation hole on the side of a ball holding chamber, and a rear ink circulation hole which gradually reduces its diameter toward the direction of ball from the rear hole side, an opening part on the side of ink circulation hole of the radial groove reaches the rear ink circulation hole.

Description

  The present invention has an ink circulation hole formed in the center of the bottom wall of the ball holding chamber in the chip body and a plurality of ink circulation grooves extending radially from the ink circulation hole, and the ball is placed on the bottom wall. The present invention relates to a ball-point pen tip that is inserted and caulked with the tip end of the tip inward so that a part of the ball protrudes from the tip end edge and is rotatably held.

  Conventionally, a ball is inserted into a ball holding chamber having an ink circulation hole in the center of the bottom wall and an ink circulation groove extending radially from the ink circulation hole, and the tip of the chip is caulked inward, thereby A ball-point pen tip is well known in which a portion is protruded from a tip end portion and is rotatably held.

  In such a conventional ballpoint pen tip, ink supply to the ball such as the size of the ink circulation hole and the formation of the ink circulation groove so as to reach the rear hole, as in JP-A-8-118896, “Correcting Pen Tip” Many proposals have been made to increase the amount.

  Further, as disclosed in Japanese Patent Application Laid-Open No. 2005-7876, “Chip for Applicator Tool, Method for Manufacturing Chip for Applicator Tool, Applicator”, the connection surface between the seating surface and the side wall surface of the ball holding chamber is directed toward the tip. An applicator having a protruding shape and a higher flowability of the coating liquid has been proposed.

JP-A-8-11896 JP 2005-7876 A

  However, in the conventional ballpoint pen tip such as Patent Document 1, for the purpose of increasing the amount of ink supply, etc., if the ink circulation groove has a shape reaching the rear hole, the addition to the processing tool etc. for forming the ink circulation groove is large, There is a problem that the manufacturing cost increases, such as the tool life is shortened.

  In addition, since the connecting surface between the seating surface and the side wall surface of the ball holding chamber has a protruding shape toward the tip, the space for storing ink increases, but the ink from the rear hole to the ball is increased. There is no solution to increase the supply.

  The present invention has been made in view of these conventional techniques, and it is an object of the present invention to provide a ballpoint pen tip that can smoothly supply ink to a ball with a simple structure.

  The present invention provides a chip body with a ball holding chamber, an ink circulation hole formed in the center of the bottom wall of the ball holding chamber, a rear hole formed behind the ink circulation hole, and the ink circulation hole. A plurality of ink flow grooves that extend radially and do not reach the rear hole, insert a ball into the bottom wall, and caulk the tip of the chip body inward to A ballpoint pen tip that protrudes outward from the tip of the tip body and is rotatably held, wherein the ink circulation hole is formed from the front ink circulation hole on the ball holding chamber side and the rear hole side. A rear ink circulation hole that gradually decreases in diameter in the ball direction is provided, and an opening on the ink circulation hole side of the radial groove reaches the rear ink circulation hole.

  Further, the front ink circulation hole is gradually reduced in diameter from the opening on the bottom wall side of the ball holding chamber toward the rear hole.

  Furthermore, the bottom wall of the ball holding chamber protrudes in the axial direction of the chip body.

  According to the configuration of claim 1 of the present invention, the ink circulation hole includes a front ink circulation hole on the ball holding chamber side and a rear ink circulation hole that gradually decreases in diameter in the ball direction from the rear hole side. In addition, since the opening on the ink circulation hole side of the radial groove reaches the rear ink circulation hole, the ballpoint pen ink is supplied smoothly from the rear hole to the rear ink circulation hole during writing. The In addition, since the opening on the ink circulation hole side of the radial groove reaches the rear ink circulation hole, ink is supplied to the radial groove even in a flow along the axial direction. As a result, the ink can be smoothly supplied to the ball.

  In addition, since the bottom wall of the ink circulation groove is not formed as a rear hole, the addition of a processing tool for the ink circulation groove can be reduced. Further, regarding the high writing pressure performance, it is preferable that the bottom wall of the ink circulation groove is not a rear hole.

  According to the configuration of claim 2 of the present invention, the front ink circulation hole gradually decreases in diameter from the opening on the bottom wall side of the ball holding chamber toward the rear hole. It is possible to amplify the opening area of the ink circulation hole and obtain a larger amount of ink supply.

  According to the configuration of claim 3 of the present invention, since the bottom wall of the ball holding chamber protrudes in the axial direction of the chip body, the space for storing the supplied ink can be increased. The opening area of the ink circulation hole in the vicinity of the ball can be amplified, and a larger amount of ink supply can be obtained.

  According to the present invention, a ballpoint pen tip that can smoothly supply ink to the ball can be provided with a simple structure.

FIG. 3 is an enlarged vertical cross-sectional view of a main part in which a part of the ball-point pen tip of Example 1 is omitted. It is AA sectional drawing which abbreviate | omitted the ball | bowl in FIG. FIG. 2 is an enlarged vertical cross-sectional view of a main part of the ball-point pen tip shown in FIG. It is a figure which shows the ball-point pen refill using the ball-point pen tip of Example 1. FIG.

Example 1
The ballpoint pen tip 1 of Example 1 shown in FIG. 1 and FIG. 2 holds a ball on a tip body 2 obtained by cutting a ferritic stainless steel wire having a diameter of 2.3 mm and a hardness of 230 Hv to 280 Hv to a desired length. Chamber 3, ink circulation hole 6 formed in the center of bottom wall 4 of ball holding chamber 3, rear hole 7 formed behind ink circulation hole 6, and radially extending from ink circulation hole 6, The four ink flow grooves 5 that do not reach are provided, the ball 8 is inserted into the bottom wall 4, and the tip portion 2 a of the chip body 2 is caulked inward, so that a part of the ball 8 is attached to the chip body 2. The ball-point pen tip 1 is obtained by projecting outward from the tip and holding it rotatably.

  The ink circulation hole 6 has a rear ink circulation hole 6 b that gradually decreases in diameter from the rear hole 7 side toward the ball 8, and an opening on the bottom wall 4 side of the ball holding chamber 3 toward the rear hole 7. The front ink circulation holes 6a that are gradually reduced in diameter are provided continuously.

  The radial groove 5 is formed so that the opening on the ink circulation hole 6 side reaches the wall surface L of the rear ink circulation hole 6b and the bottom wall 5a of the radial groove 5 does not reach the rear hole 7. The bottom wall 4 of the ball holding chamber 3 is provided so as to protrude in the direction of the axis J of the chip body 2.

  The ball pen tip manufacturing method will be described in detail. As shown in FIG. 3, the tip body 2, the ball holding chamber 3, the ink circulation hole 6 in the center of the bottom wall 4 of the ball holding chamber 3, and the rear hole 7 are provided. After that, the pressing tool 9 is pressed from the rear hole 7 side toward the tip, and the bottom wall 4 of the ball holding chamber 3 is formed to protrude toward the axis J direction of the chip body 2. After that, the ball pen tip of the present invention can be obtained by forming the ink circulation groove 2 that extends radially from the ink circulation hole 6, reaches the rear ink circulation hole 6 b, and does not reach the rear hole 9. The pressing tool is provided with an outer wall M that is substantially the same shape as the inner wall L of the rear ink circulation hole 6b.

  The method of manufacturing the ballpoint pen tip of the present invention is not particularly limited, but the shape in which the bottom wall of the ball holding chamber protrudes toward the axial direction of the tip body and the ball direction from the rear hole side. Since the rear ink circulation hole gradually decreasing in diameter toward the rear and the front ink circulation hole gradually decreasing in diameter toward the rear hole from the opening on the bottom wall side of the ball holding chamber can be formed simultaneously. The production method is preferred.

  FIG. 4 shows an example in which the ball-point pen tip 1 of the present invention is used as the ball-point pen refill 10. Specifically, the ballpoint pen tip 1 of the present invention is attached to the tip of the ink containing cylinder 11. In the ink storage cylinder 11, a water-based ballpoint pen ink 13 imparted with shear thinning viscosity and a grease-like ink follower 14 are stored.

  When writing on the paper surface using this ball-point refill 10, the ball-point pen ink 13 in the ink containing cylinder 11 passes from the rear hole 8 of the ball-point pen tip 11 to the rear ink circulation hole 6b, the front ink circulation hole 6a, and the ink circulation groove 5. 8 and the ball holding chamber 3. The ball-point pen ink 13 supplied to the ball 8 and the ball holding chamber 3 has a gap between the ball 8 and the inner wall of the tip end portion of the chip body 2 against the pressing force of the coil spring 12 that presses the ball 8 by the writing pressure. Can be written out from the gap on the paper surface.

  The ballpoint pen tip of the present invention can be used without being limited to the ink used, and can be used regardless of the type of ink, such as oil-based ballpoint pen ink, water-based ballpoint pen ink, ink with shear thinning viscosity, and correction ink. Therefore, it can be widely used as a ball-point pen tip using a ball as a writing medium, and can be effectively used particularly when the ink consumption is increased.

DESCRIPTION OF SYMBOLS 1 Ball-point pen tip 2 Tip body 2a Tip part 3 Ball holding chamber 4 Bottom wall 5 Ink flow groove 6 Ink flow hole 6a Front ink flow hole 6b Rear ink flow hole 7 Rear hole 8 Ball

Claims (3)

In the chip body, a ball holding chamber, an ink circulation hole formed in the center of the bottom wall of the ball holding chamber, a rear hole formed behind the ink circulation hole, and radially extending from the ink circulation hole, A plurality of ink circulation grooves that do not reach the rear hole, and a ball is inserted into the bottom wall, and the tip of the chip body is caulked inward, whereby a part of the ball is moved to the tip of the chip body. A ball-point pen tip that protrudes outward from a portion and is rotatably held, wherein the ink circulation holes are directed from the front ink circulation hole on the ball holding chamber side to the ball direction from the rear hole side. And a rear ink circulation hole that gradually decreases in diameter, and the opening on the ink circulation hole side of the radial groove reaches the rear ink circulation hole. 2. The ballpoint pen tip according to claim 1, wherein the diameter of the front ink circulation hole gradually decreases from the opening on the bottom wall side of the ball holding chamber toward the rear hole. 3. The ballpoint pen tip according to claim 1, wherein a bottom wall of the ball holding chamber protrudes in an axial direction of the tip body.

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