JP6445754B2 - Ballpoint pen tip and ballpoint pen using the tip - Google Patents

Description

  The present invention relates to a ballpoint pen tip including a cylindrical holder part in which an ink guide hole communicating from the rear end to the front end is formed, and a writing ball rotatably held inside the front end of the holder part. The present invention relates to a ballpoint pen using the ballpoint pen tip.

Conventionally, a ballpoint pen as a writing instrument has been used.
The ball-point pen has a ball-point pen tip disposed at the tip portion and a writing ball that is rotatably embedded at the tip. When the writing ball at the tip of the ballpoint pen tip rotates on the writing surface, ink on the back side of the writing ball is sent to the pen tip surface to draw a line.

In addition to the above-mentioned writing ball, the ball-point pen tip provided in such a ball-point pen is provided with a cylindrical holder portion in which an ink guide hole communicating from the rear end to the front end is formed.
And the crimping | crimped part formed by bending the peripheral part of the opening in the said front end toward the inner side is provided in the front-end | tip of this holder part. The crimping portion holds a writing ball rotatably provided inside the tip of the holder portion so as not to come out of the holder portion.

Here, in order to improve the design of the ballpoint pen tip, it is known that a conical taper portion is formed from the maximum outer diameter portion of the holder portion to the vicinity of the crimped portion at the tip. (For example, refer to Patent Document 1).
In the ballpoint pen having such a ballpoint pen tip, the pen tip is behind the conical taper portion, so that the drawn line portion of the pen tip may be difficult to see.
Therefore, instead of the tapered portion formed in a conical shape to form an end face of the axial direction and Cartesian to the end of the maximum outer diameter portion of the holder portion, and an elongated cylindrical shape protruding toward this end face to the tip It is known that a pipe ball is provided and a writing ball is rotatably accommodated at the tip of the pipe portion, thereby making it easy to see the drawn portion of the pen tip (for example, see Patent Document 1).

JP 2002-326487 A

  In the ball pan chip as described above, when the cylindrical pipe portion is provided, it is possible to make the drawn portion of the pen nib easy to see, but the pipe portion protruding from the planar end surface forms a rustic appearance. The design cannot be made excellent. On the other hand, if a conical taper portion is provided, the design can be improved, but it is not easy to see the drawn part of the nib, so that the drawn part of the nib is easy to see and an excellent design. There is a need for ballpoint pen tips and ballpoint pens having

  Therefore, the present invention has been made in view of the problems of the above-described conventional techniques, and the object of the present invention is to provide a ball-point pen tip having an excellent design that makes it easy to see the drawn portion of the pen tip. To provide a ballpoint pen.

The present invention has been made to achieve the aforementioned object. The features of the present invention will be described below using the embodiments of the present invention shown in the drawings.
In addition, a code | symbol shows the code | symbol used in embodiment of this invention, and does not limit the technical scope of this invention.

(First invention)
(Feature point)
The first aspect of the present invention is characterized by the following points.
That is, according to the first aspect of the present invention, a cylindrical holder part (11) in which an ink guide hole communicating from the rear end to the front end is formed is provided inside the front end of the holder part (11) so as to be rotatable. Formed by bending the writing ball (12) and the peripheral portion of the tip opening of the holder part (11) inwardly, holding the writing ball (12) so as not to come out of the holder part (11) A ballpoint pen tip (10) provided with a crimping portion (13), the tip portion of the holder portion (11) being directed from the maximum outer diameter portion (14) of the holder portion (11) toward the tip A reduced diameter portion (15) whose outer diameter is gradually reduced to the vicinity of the crimped portion (13) is provided, and the reduced diameter portion 15 has a concave curved side surface.

(Second invention)
(Feature point)
The second invention of the present invention is an invention related to the ballpoint pen (1), characterized in that it comprises the ballpoint pen tip (10) of the first invention described above.

(Effect of the invention)
The present invention configured as described above has the following effects.
That is, in the present invention, the tip part of the holder part of the ballpoint pen tip is provided with a reduced diameter part in which the outer diameter gradually decreases from the maximum outer diameter part of the holder part toward the tip, and near the crimped part, Since the side surface of the portion is a concave curved surface, the outer diameter is sufficiently small in the vicinity of the caulking portion, so that the writing ball at the pen tip and the drawn line portion thereby can be easily seen. This is effective in making it easy for the user to recognize the minuteness of a small writing ball having an outer diameter of 0.55 mm or less. Moreover, a continuous curved surface is formed from the maximum outer diameter part of the holder part to the vicinity of the caulking part by the reduced diameter part whose side surface is a concave curved surface, so that the appearance of a sophisticated impression is formed, so the design is excellent. In this way, the object can be achieved. Also, by making the side of the reduced diameter part a concave curved surface, stress concentration is less likely to occur in the reduced diameter part of the tip than in the case of a ballpoint pen tip with a cylindrical pipe part. It can also improve the performance.

It is a top view which shows the ball-point pen which concerns on one Embodiment of this invention. It is a side view which shows the ball-point pen which concerns on the said embodiment. It is a side view of the nib exposure state which shows the ball-point pen concerning the embodiment. It is an enlarged side view which shows the pen point of the ball-point pen which concerns on the said embodiment. It is a perspective view which shows the ball-point pen tip which concerns on the said embodiment. It is a side view which shows the ball-point pen tip which concerns on the said embodiment. It is sectional drawing which shows the ball chip based on one Example of this invention. It is sectional drawing which shows the ball-point pen tip concerning a comparative example.

  Hereinafter, an embodiment, which is a mode for carrying out the present invention, will be described with reference to the drawings.

(Schematic configuration of the ballpoint pen 1)
As shown in FIGS. 1 to 3, the ballpoint pen 1 according to the first embodiment includes a cap 2 that covers the pen tip for protection and a shaft cylinder 3 that accommodates a ballpoint refill (not shown). It has become. Further, a ballpoint pen tip 10 according to the present invention is provided at the tip of a ballpoint refill (not shown) (see FIGS. 5 and 6).

The cap 2 is a short member formed in a cylindrical shape. The cylindrical shape of the cap 2 has one end closed and the other end opened.
Further, the cap 2 is provided with a clip portion 2A that is hooked on the cloth of the pocket when the ballpoint pen 1 whose pen tip is covered with the cap 2 is inserted into the pocket of the clothes.

As shown in FIGS. 2 and 3, the clip portion 2 </ b> A has a base portion integrated with the closed end portion of the cap 2. A portion from the base portion to the middle of the clip portion 2A is a curved portion 2B that is gently curved. The portion on the tip side of the curved portion 2B is a straight portion 2C that extends substantially straight.
An abutting protrusion 2D that abuts against the fabric of the pocket is provided at a portion facing the side surface of the cap 2 in the vicinity of the tip of the clip portion 2A.

The shaft cylinder 3 is an elongated member that is formed in a cylindrical shape and is open at both ends of the cylindrical shape. The cap 2 is detachably fitted to a portion of the shaft tube 3 on the tip 3A side.
On the other hand, referring back to FIGS. 1 and 2, the rear end 3B of the shaft tube 3 is detachably fitted to the rear end 3B as shown in FIGS. . In addition, a substantially cylindrical tail plug 3C is fitted into the end opening on the rear end 3B side of the shaft tube 3.

As shown in FIG. 3, a truncated cone-shaped front shaft portion 3D is screwed into the end opening on the tip 3A side of the shaft tube 3. Further, on the side surface of the shaft tube 3 in the vicinity of the tip 3A, a grip portion 3E formed with a slip stopper is provided.
Here, the front shaft portion 3D has an open end surface. In other words, as shown in FIGS. 3 and 4, an opening 3F is formed on the tip surface of the front shaft portion 3D.
As shown in FIGS. 3 and 4, the ballpoint pen refill (not shown) housed in the shaft tube 3 can be visually recognized with the tip end 1A of the tip exposed to the outside through the opening 3F of the tip 3D. Yes. The pen tip 1A is formed at the tip of a ballpoint pen tip 10 described below.

(Ballpoint pen tip 10)
5 and 6, the ball-point pen tip 10 includes a cylindrical holder portion 11 in which an ink guide hole (not shown) communicating from the rear end to the front end is formed, and the holder as shown in FIGS. A writing ball 12 rotatably provided inside the tip of the portion 11 and a crimping portion 13 that holds the writing ball 12 so as not to come out of the holder portion 11 are provided.

5 and 6, the holder portion 11 has a cylindrical maximum outer diameter portion 14 that is a maximum outer diameter portion having the largest outer diameter at the center portion.
A tapered reduced diameter portion 15 is provided on the distal end side of the holder portion 11, in other words, on the right side in FIG.
A portion on the rear end side of the holder portion 11, in other words, a right portion in FIG. 6 is a fixing portion 16 to which an ink storage tube of a ballpoint refill (not shown) is fixed.

The reduced diameter portion 15 has an outer diameter that gradually decreases from the maximum outer diameter portion 14 of the holder portion 11 to the vicinity of the crimping portion 13 toward the tip.
Further, the side surface of the reduced diameter portion 15 is a concave curved surface that is recessed toward the central axis side of the holder portion 11. In other words, in FIG. 6, the contour of the side surface of the reduced diameter portion 15 is a continuous curve extending from the maximum outer diameter portion 14 toward the tip, and has a steep slope in the vicinity of the maximum outer diameter portion 14. However, the slope becomes gradually gentler toward the vicinity of the tip.

The fixed portion 16 is a cylindrical portion whose outer diameter is slightly smaller than that of the maximum outer diameter portion 14. The boundary portion between the fixed portion 16 and the maximum outer diameter portion 14 is a stepped portion 17.
The rear portion of the fixing portion 16 is a locking portion 16A having a slightly larger outer diameter than the front portion. An ink storage tube (not shown) is fitted into the fixing portion 16, and the fitted ink storage tube is locked by the locking portion 16A so that it is not easily detached from the fixing portion 16.

The writing ball 12 is rotated in contact with the surface to be written at the tip portion of the ball-point pen chip 10, thereby attaching the ink on the back side of the writing ball 12 to the surface to be written.
The crimping portion 13 is formed by bending the peripheral portion of the tip opening of the holder portion 11 inward so that the writing ball 12 does not come out of the holder portion 11.

(Effect of embodiment)
According to this embodiment as described above, the following effects can be obtained.
That is, a reduced diameter portion 15 whose outer diameter gradually decreases from the maximum outer diameter portion 14 of the ballpoint pen tip 10 to the vicinity of the caulking portion 13 is provided at the distal end portion of the holder portion 11, and Since the side surface of the diameter portion 15 is a concave curved surface, the outer diameter is sufficiently small in the vicinity of the caulking portion 13, and the writing ball 12 at the nib and the drawn line portion thereby can be easily seen. This is effective in that the user can easily recognize the minuteness when the minute writing ball 12 having a ball diameter of 0.55 mm or less is used. In addition, a continuous curved surface is formed from the maximum outer diameter portion 14 of the holder portion 11 to the vicinity of the caulking portion 13 by the reduced diameter portion 15 whose side surface is a concave curved surface, so that a sophisticated impression appearance can be formed. Thus, the design of the ballpoint pen tip 10 can be made excellent. As a result, the design of the ballpoint pen 1 can also be made excellent. In addition, by making the side surface of the reduced diameter portion 15 a concave curved surface, stress concentration is less likely to occur in the reduced diameter portion 15 compared to a ballpoint pen tip having a cylindrical pipe portion. It can also improve the performance.

The effects of the present invention will be specifically described based on experiments using the following examples and comparative examples.
[Example]
The ball-point pen tip 10 according to the present example is based on the above embodiment, and as shown in FIG. 7, the outer diameter gradually decreases from the maximum outer diameter part 14 of the holder part 11 to the vicinity of the caulking part 13 toward the tip. The reduced-diameter portion 15 is provided, and the side surface of the reduced-diameter portion 15 is a concave curved surface.
[Comparative example]
The ball-point pen tip 30 according to the present comparative example does not include the reduced diameter portion based on the present invention, and as shown in FIG. 8, the outer periphery extends from the maximum outer diameter portion 34 of the holder portion 31 toward the crimping portion 33 at the tip. A first tapered portion 35 whose surface is a conical surface, a pipe portion 36 whose outer peripheral surface is a cylindrical surface, and a second tapered portion 37 whose outer peripheral surface is a conical surface are sequentially provided. .

〔experimental method〕
For each three samples of the above Examples and Comparative Examples, the pressing force of the axial direction and Cartesian the tip portion of the ballpoint pen tip 10, 30, i.e., a bending load is applied, further, increase the bending weighted An experiment was conducted to determine the bending load at which bending or breaking started.

Here, the ballpoint pen tips 10 and 30 have a total length of 12 mm, the diameter of each writing ball 12 is 0.38 mm, and a position α (2 mm from the tip, FIG. The outer diameter and inner diameter in FIG. 8) were 1.0 mm and 0.6 mm, respectively.
When applying bending load to the tip of the ballpoint pen tip 10, 30, the vise β is a predetermined position of the maximum outer diameter portion 14, 43, specifically, a position 4.5mm away from the position α along the axis. Grabbed and fixed. The position where the bending load is applied is a position where the thicknesses at the tip portions of the ballpoint pen tips 10 and 30 are the same. Specifically, as described above, in FIGS. 7 and 8, a bending load was applied to a position α 2 mm away from the tip.

〔Experimental result〕
In the ballpoint pen tip 10 of the example, when the bending load to the position α was increased, bending occurred at a portion near the position α at a certain time. The bending load at this time was 205 N as an average value of three samples.
On the other hand, in the ballpoint pen tip 30 of the comparative example, when the bending load to the position α was increased, the boundary portion between the first tapered portion 35 and the pipe portion 36 was broken at a certain point. The bending load at this time was 70 N as an average value of three samples.
From the above experimental results, it has been found that according to the embodiment of the present invention, there is an effect that the rigidity and durability against bending load can be improved.

In addition, this invention is not limited to the said embodiment, The deformation | transformation in the range which can achieve the objective of this invention, improvement, etc. are included.
For example, the ballpoint pen is not limited to a cap-type ballpoint pen that protects the nib with the cap 2, but the nib can be moved by moving a knock body provided at the rear end or side surface of the axial tube in the axial direction. It can be stored inside the cylinder, so that it can be knocked to protect the nib, or by rotating one of the two divided cylinders with respect to the other, the nib is inside the cylinder. It may be a retractable type such as a rotating ballpoint pen that is housed in the housing and thereby protects the pen tip.

1 Ballpoint pen 1A Pen tip 2 Cap 2A Clip
2B Curved part 2C Straight part
2D abutment projection 3 shaft cylinder
3A tip 3B back end
3C Tail plug 3D Tip shaft
3E Grip part 3F opening
10 Ballpoint pen tip 11 Holder
12 Writing balls 13 Caulking section
14 Maximum outer diameter 15 Reduced diameter
16 Fixed part 16A Locking part
17 Stepped part

Claims (2)

With a fixed portion slightly outer diameter is smaller cylindrical portion with fitted into the front end of the ink storage tube accommodated in the barrel is formed on the rear end side, the ink guide hole communicating with the rear end to the tip A cylindrical holder formed inside,
A writing ball having a diameter of 0.55 mm or less, which is rotatably provided inside the tip of the holder,
A caulking portion that is formed by bending inward the peripheral portion of the tip opening of the holder portion, and holds the writing ball so as not to come out of the holder portion;
A ballpoint pen tip with
The maximum outer diameter part of the holder part is cylindrical,
The distal end portion of the holder portion is provided with a reduced diameter portion whose outer diameter gradually decreases from the maximum outer diameter portion of the holder portion toward the tip toward the vicinity of the caulking portion,
This reduced diameter portion has a concave curved side surface. Ballpoint pen characterized by comprising a claim 1 Symbol placement of the ballpoint pen tip.

Images