JP2006289807A - Ball-point pen tip and ball-point pen using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a ball-point pen tip excellent in ink following properties, without reference to the type and viscosity of ink, and a ball-point pen using the ball-point pen tip. <P>SOLUTION: In this ball-point pen tip, a ball is rotatably held in a ball holding chamber at the leading end of the tip; and an ink circulation hole communicating with an inner hole at the rear end of the tip, and ink circulating grooves radially elongated from the ink circulating hole are provided in the center of the bottom wall of the ball holding chamber. The ball-point pen tip is characterized in that the ink circulating groove alternately forms two types of grooves different in groove width. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a ballpoint pen tip formed by rotatably holding a ball in a ball holding chamber at the tip of the tip and a ballpoint pen using the same.

  Conventionally, a ball-point pen tip having an ink circulation groove communicating with an ink circulation hole at the center of the bottom wall of the ball holding chamber is well known. In such a ball-point pen tip, as in Japanese Utility Model Laid-Open No. 7-31382 “Ball Pen”, an ink groove extending radially from the ink circulation hole and reaching the inner hole at the rear end of the chip, or Japanese Utility Model Laid-Open No. 7-31382 “ball-point pen”. As described above, an ink circulation groove of a type that extends radially from the ink circulation hole and does not reach the inner hole at the rear end of the chip is well known.

  The ink groove that extends radially from the former ink circulation hole and reaches the inner hole at the rear end of the chip has a problem that the addition to the tool is large during manufacture and the tool life is short. The ink distribution groove of the type that extends and does not reach the inner hole of the rear end portion of the chip can reduce the manufacturing cost.

  In such a ball-point pen tip having an ink distribution groove that extends radially from the ink distribution hole and does not reach the inner hole at the rear end of the chip, Japanese Patent Application Laid-Open No. 8-207482 “Metal chip for ball-point pen” includes an ink distribution hole. There is disclosed a ballpoint pen tip in which the diameter of the ink and the length of the ink circulation hole are made to be a fixed ratio, and the ink repelling after being left facing upward is prevented from blurring and the ink followability at high speed writing is improved.

In consideration of ink followability, as disclosed in Patent Document 2, the diameter of the ink circulation hole and the length of the ink circulation hole are one of the important requirements. As described in “Ball Pen Tip” and the like, the size of the ink circulation groove is also largely attributed to the ink following ability.
“Japanese Utility Model Publication No. 7-31382” "JP-A-8-207482"

  By the way, inks used for ballpoint pens are roughly classified into two types of oil-based inks and water-based inks, and the ink ejection mechanisms are also different.

  This is because the former oil-based ink ejection mechanism turns the pen tip ball and the ink adhering to the ball is transferred to the writing surface, while the latter water-based ink ejection mechanism is Against the background of the rotation of the ball at the tip of the pen, the ink ejection mechanism is different, for example, the ink is transferred to the writing surface by capillary / penetration action, resulting in handwriting.

  As described above, since the mechanism of ink tracking varies depending on the ink characteristics, the ballpoint pen tip structure is actually set according to the characteristics of each ink.

  An object of the present invention is to provide a ball-point pen tip excellent in ink followability regardless of the type and viscosity of ink and a ball-point pen using the same.

The present invention
“1. The present invention includes an ink circulation hole that rotatably holds a ball in a ball holding chamber at a tip end of the chip, and communicates with an inner hole in a rear end portion of the chip at the center of the bottom wall of the ball holding chamber. In the ball-point pen tip having the ink circulation groove extending radially from the ink circulation hole, the ink circulation groove is formed by alternately forming two kinds of grooves having different groove widths.
2. 2. The ballpoint pen tip according to claim 1, wherein the two kinds of grooves having different groove widths have the same circumscribed circle.
3. The two types of grooves having different groove widths are such that the groove having the smaller groove width is formed deeper in the chip rear end direction than the depth of the other groove. The ballpoint pen tip according to item.
4). 4. The ballpoint pen tip according to claim 1, wherein the ink circulation groove is formed symmetrically with respect to the center of the ink circulation hole.
5. The ink distribution groove is composed of two types of groove widths of 5% to 20% of the ball diameter and 10% to 30% of the ball diameter, and the groove width of 5% to 20% is S, 10% to 5. The ballpoint pen tip according to item 4, wherein S <T is satisfied when T is a groove width of 30%.
6). A ball seat having the same shape as the ball is formed on the bottom wall of the ball holding chamber, and the projected area of the ball seat is 15% to 35% of the maximum cross-sectional area of the ball. The ball-point pen tip of any one of claim | items.
7). A ball-point pen in which the ballpoint pen tip according to any one of items 1 to 6 is mounted on a tip of an ink containing cylinder, and the ink containing cylinder contains pigment or resin particles having a particle size of 1 μm or more. A ballpoint pen characterized by containing ink for ballpoint pen. "
It is.

  It was possible to provide a ballpoint pen tip excellent in ink followability regardless of the type and viscosity of the ink and a ballpoint pen using the same.

  Next, embodiments of the ballpoint pen tip and the ballpoint pen using the same according to the present invention will be described with reference to the drawings. However, the present invention is not limited to the following embodiments.

  The ball-point pen tip 1 shown in FIGS. 1 to 3 is formed with a ball seat 7 having substantially the same shape as the ball 11 on the bottom wall 4 of the ball holding chamber 2 of the chip body, and the ball 11 is placed on the ball seat 7. The ball 11 is rotatably held by forming the caulking portion 9 by caulking the tip end edge 8 inside. The bottom wall 4 of the ball holding chamber 2 has an ink circulation hole 3 communicating with the inner hole 10 at the rear end of the chip, and extends radially from the ink circulation hole 3 to the inner hole 10 at the rear end of the chip. Eight ink flow grooves 5, 6 that do not communicate are formed.

  The ink circulation grooves 5 and 6 are formed by alternately forming two types of grooves having two different groove widths, and the groove width S1 of the ink circulation groove 5 is smaller than the groove width T1 of the ink circulation groove 6. . (S1 <T1) The ink circulation grooves 5 and 6 are formed symmetrically with respect to the center of the ink circulation hole 3.

  The ink distribution groove 5 having a small groove width contributes to an improvement in ink followability of the water-based ink. This is because the capillary action tends to work when the groove width is small. The groove width of the present invention indicates the maximum widths S1 and T1 of the groove width obtained by a longitudinal section as shown in FIGS.

  On the other hand, the oil-based ink is transferred to the writing surface because the ink adhering to the ball 11 is transferred to the writing surface, so the ink circulation grooves 5 and 6 work as a space for storing the ink. By increasing the ink followability, the ink circulation groove 6 having a groove width larger than the ink circulation groove 5 is formed.

  The shape of the ink circulation grooves 5 and 6 is not particularly limited, but if the circumscribed circle R of the ink circulation grooves 5 and 6 is different, there is a possibility that the ink does not uniformly adhere to the ball 11. It is preferable to make the circumscribed circle R1 of the same.

  Further, the number of the ink circulation grooves 5 and 6 is not particularly limited, but two types of ink circulation grooves having different groove widths are alternately formed and symmetrical with respect to the center of the ink circulation hole 3, for example, six or eight. It is preferable to form them individually because the ink supplied to the balls 11 is not easily biased.

  When the ink circulation groove 3 is symmetrical with respect to the center of the ink circulation hole 3, the groove width of the ink circulation groove is 5% to 20% of the ball diameter with a small groove width, and 10% to 30% of the ball diameter with a large groove width. It is preferable that This is because if the small groove width is less than 5% of the ball diameter, the capillary force tends to work, but the components in the ink may clog the ink distribution groove and close the ink distribution groove. This is because if the ratio exceeds 50%, the action of the capillary force is deteriorated and the followability is lowered. In addition, if the large groove width is less than 10% of the ball diameter, the space for storing ink is small and the followability is poor, and if it exceeds 30%, it is symmetrical with respect to the center of the ink circulation hole. This is because, since a total of six or more ink distribution grooves are required, the number of portions for forming the ink distribution grooves with a small groove width is reduced, and thus the manufacture becomes difficult. On the other hand, if it exceeds 30%, the contact area between the ball and the ball seat is reduced, and the ball seat is easily worn.

  The ball-point pen tip 21 shown in FIGS. 4 to 6 is formed with a ball seat 27 having substantially the same shape as the ball 11 on the bottom wall 24 of the ball holding chamber 22 of the tip body in the same manner as in the first embodiment. The ball 11 is placed on 27 and the tip end edge 28 is caulked on the inner side to form a caulking portion 29, whereby the ball 11 is rotatably held to obtain the ball-point pen tip 21.

  The bottom wall 24 of the ball holding chamber 22 has an ink circulation hole 23 communicating with the inner hole 30 at the rear end of the chip, and extends radially from the ink circulation hole 3 to the inner hole 10 at the rear end of the chip. A total of eight ink circulation grooves 25 and 26 that do not communicate with each other are formed by alternately forming four grooves of two types having different groove widths. As in the first embodiment, the groove width S2 of the ink circulation groove 25 is smaller than the groove width T2 of the ink circulation groove 26 (S2 <T2), and is formed symmetrically with respect to the ink circulation hole 23. The circumscribed circle R1 of the ink circulation grooves 25 and 26 is the same.

  A depth L of the ink circulation groove 25 having a small groove width S2 is formed deeper (M <L) in the chip rear end side than a depth M of the ink circulation groove 26 having a large groove width T2. The depth of the ink circulation grooves 25 and 26 is not particularly limited, but it is preferable not to form them too deep considering the life of the tool. However, since the capillary action is easier to work in the axial direction, the ink followability is further improved. In order to improve, it is preferable that only the ink circulation groove 25 having a small groove width is formed deep in the direction of the chip rear end. The depth of the groove of the present invention is the depth of the portion connected to the ink circulation hole 23.

  As shown in FIG. 7, when the ballpoint pen tip of the present invention is used as a ballpoint pen, for example, the ballpoint tip 1 of Example 1 is attached to the tip of the ink containing cylinder 42 and the rear end of the ink containing cylinder is used. A ball-point pen 41 can be obtained by mounting the ball-point pen ink 44 in the ink-receiving cylinder 42. Further, in this embodiment, a coil-like spring 46 is disposed in the grease-like ink follower 45 that follows the ink 44 and the ballpoint pen tip.

  Although the ink for ball-point pens is not particularly limited, the ball-point pen tip of the present invention is particularly effective for a ball-point pen using an aqueous ball-point pen ink containing pigments and / or resin particles having a particle diameter of 1 μm or more. As described above, the capillary action is more easily performed when the groove width is smaller, but pigments and / or resin particles having a particle diameter of 1 μm or more are clogged up in the ink circulation groove to close the ink circulation groove. There is a possibility, but the ballpoint pen tip of the present invention has two kinds of ink circulation grooves having different groove widths, so that even if the narrow groove is closed, the ink flow is obtained by the large groove. This is because it is possible to prevent the inability to write.

  In this embodiment, for convenience, the ball seat is formed on the bottom wall of the ball holding chamber, but a structure in which the ball seat is not formed may be used. In addition, since the ink pendant grooves having different groove widths are alternately formed, for example, four in the ballpoint pen tip of the present invention as in the embodiment, only one (four) groove widths are changed. Since the contact area between the ball and the bottom wall of the ball holding chamber is changed, the bottom of the ball and the ball holding chamber is compared with a conventional ballpoint pen tip formed with a plurality of, for example, eight, ink circulation grooves having the same shape. Easy to change the contact area with the wall, considering not only ink followability, but also writing quality due to the difference in contact area between the ball and the bottom wall of the ball holding chamber and wear of the bottom wall of the ball holding chamber Since it can produce, it is preferable.

  In addition, when forming a ball seat, a ball seat with a small projected area is prone to dents and wear, so the ball seat projection area is the maximum of the ball against dents and wear. The thing of 15% or more of a cross-sectional area is good. In addition, it is well known that the ball should not have a ball seat diameter that closes the radial groove 5 in order to cause ink to flow out from the tip end without causing line blurring during handwriting. 35% or less of the maximum cross-sectional area of the ball is preferable. The projected area of the ball seat is an area expressed by projecting an area where the ball contacts the bottom wall onto a plane.

  It can be carried out without being limited to the type of ink and ink viscosity, such as oil-based ink, shear thinning ink, and water-based ink.

It is the longitudinal cross-sectional view which abbreviate | omitted partially which shows the ball-point pen tip of Example 1. FIG. It is the longitudinal cross-sectional view which abbreviate | omitted partially which shows the state rotated 45 degree | times in FIG. It is AA sectional drawing which abbreviate | omitted the ball | bowl which shows the state before forming the ball seat in FIG. It is the longitudinal cross-sectional view which abbreviate | omitted partially which shows the ball-point pen tip of Example 2. FIG. It is the longitudinal cross-sectional view which a part of which showed the state rotated 45 degree | times in FIG. 4 was abbreviate | omitted. It is AA sectional drawing which abbreviate | omitted the ball | bowl which shows the state before forming the ball seat in FIG. It is the longitudinal cross-sectional view which abbreviate | omitted one part of the ball-point pen equipped with the ball-point pen tip of this invention.

Explanation of symbols

1, 21 Ball pen tip 2, 22 Ball holding chamber 3, 23 Ink flow hole 4, 24 Bottom wall 5, 25 Ink flow groove 6, 26 Ink flow groove 7, 27 Ball seat 8, 28 Tip end 9, 29 Caulking Part 10, 30 Tip rear hole 11 Ball 41 Ballpoint pen

Claims (7)

A ball is rotatably held in a ball holding chamber at the tip of the chip, an ink circulation hole communicating with an inner hole in the rear end of the chip at the center of the bottom wall of the ball holding chamber, and a radial shape from the ink circulation hole A ball-point pen tip having an ink circulation groove extending in the shape, wherein the ink circulation groove is formed by alternately forming two types of grooves having different groove widths. The ballpoint pen tip according to claim 1, wherein the two kinds of grooves having different groove widths have the same circumscribed circle. 3. The two types of grooves having different groove widths, wherein the groove having the smaller groove width is formed deeper in the chip rear end direction than the depth of the other groove. Ballpoint pen tip as described. 4. The ballpoint pen tip according to claim 1, wherein the ink circulation groove is formed symmetrically with respect to the center of the ink circulation hole. The ink distribution groove is composed of two types of groove widths of 5% to 20% of the ball diameter and 10% to 30% of the ball diameter, and the groove width of 5% to 20% is S, 10% to 5. The ballpoint pen tip according to claim 4, wherein S <T is satisfied, where T is a groove width of 30%. 6. A ball seat having the same shape as the ball is formed on the bottom wall of the ball holding chamber, and the projected area of the ball seat is 15% to 35% of the maximum cross-sectional area of the ball. The ball-point pen tip of any one. A ballpoint pen having the ballpoint pen tip according to any one of claims 1 to 5 attached to a tip of an ink storage cylinder, wherein the ink storage cylinder contains a pigment or a resin particle having a particle size of 1 µm or more. A ballpoint pen containing ink for use.

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