JP2003341277A - Method for manufacturing refill for retractable ballpoint pen - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a refill 1 for a retractable ballpoint pen which prevents an ink or a follower from being pushed out to the outside when a spring locking projection is formed and which can smoothly press fit a writing tip without increasing manufacturing processes. <P>SOLUTION: The method for manufacturing the refill 1 for the retractable ballpoint pen comprises a step of forming the spring locking projection 31 by press deforming the outer surface of an ink containing tube 3 made of a synthetic resin. The method further comprises the steps of filling the ink 4 in the tube 3, and disposing the front end of the ink 4 in the front end opening of the tube 3, press fitting fixedly the writing tip 2 to the front end opening of the tube 3, and filling the follower advancing in association with the consumption of the ink 4 at the rear end of the ink 4 in the tube 3. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a refill for a retractable ballpoint pen. More specifically, the present invention relates to a method of manufacturing a retractable ball-point pen refill in which a spring locking protrusion is formed on an outer surface of an ink containing tube made of synthetic resin by pressure deformation. In the present invention, “front” refers to the pen tip side, and “rear” refers to the opposite side.

[0002]

2. Description of the Related Art Conventionally, a refill for a retractable ballpoint pen is
The retractable ballpoint pen is housed inside the shaft cylinder by being elastically urged rearward by a spring, and the pen tip of the refill tip is retractable from the tip hole of the shaft cylinder by a knocking operation or a rotating operation. In the retractable ball-point pen refill, there is known one in which a spring locking protrusion is formed by pressing deformation on the outer surface of an ink containing tube made of synthetic resin.

In the conventional retractable ball-point pen refill, the outer surface of the ink containing tube is projected outward in the radial direction due to the pressing deformation, whereby a spring locking projection is formed on the outer surface of the ink containing tube. The inner surface of the ink containing tube is deformed by reducing its diameter. At the time of the pressing deformation, when the pen tip is fixed to the front end of the ink containing tube and the ink is contained inside the ink containing tube, the inner surface of the ink containing tube is reduced in diameter and deformed. As a result, the ink in the ink containing tube may move rearward, and the ink may leak from the rear end opening of the ink containing tube. The ink migration is more likely to occur with water-based inks than with oil-based inks. Furthermore, at the rear end of the ink in the ink storage tube,
In the case of a type in which a follower made of a high-viscosity fluid that advances as the ink is consumed is accommodated, the follower is pushed out from the rear end opening of the ink containing tube, or the ink is contained in the follower. There is a risk that the ink that has permeated will not return to the ink in front of the follower.

Further, in a conventional method of manufacturing a ballpoint pen, as a method for smoothly press-fitting the pen tip into the opening of the ink containing tube, for example, Japanese Patent Laid-Open No. 7-299986.
Japanese Unexamined Patent Publication (Kokai) No. Hei 9 (1999) -242242 discloses a manufacturing method in which a lubricant is applied to the outer surface of a holder (corresponding to the pen tip of the present application) and then the holder is press-fitted and fixed to the inner surface of the opening of the ink containing tube. In JP-A-226287, a tip holder (corresponding to a pen tip of the present application) is inked after a conical surface of a pressing pin is pressed against an inner peripheral edge portion (corresponding to an inner peripheral edge portion of the present application) of an opening of an ink containing tube. A manufacturing method of press-fitting and fixing to an opening of a housing tube is disclosed. However, these are all
A special manufacturing process (that is, a lubricant applying process or a pressure pin pressing process) for smooth press-fitting of the pen tip is required, which increases the manufacturing cost.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and prevents the ink and the follower from being pushed out to the outside when forming the spring locking projection. Moreover, it is an object of the present invention to provide a method for manufacturing a retractable ballpoint pen refill that enables smooth press-fitting of the pen tip without increasing the number of manufacturing steps.

[0006]

[1] A first invention of the present application is to form a spring locking projection 31 on an outer surface of an ink containing tube 3 made of a synthetic resin by pressing deformation, and then to form the ink containing tube 3 The manufacturing method (claim 1) of the retractable ballpoint pen refill 1 in which the ink 4 is filled is required.

According to claim 1, the spring locking projection 31
When the outer surface of the ink containing tube 3 is pressed and deformed to form the ink, the ink 4 is not filled in the ink containing tube 3 even if the inner surface of the ink containing tube 3 is deformed by the pressing deformation. Therefore, there is no possibility that the ink 4 leaks due to the movement of the ink 4.

[2] In the second invention of the present application, after the spring locking projection 31 is formed on the outer surface of the ink containing tube 3 made of synthetic resin by pressure deformation, the ink 4 is filled in the ink containing tube 3. Then, after that, the trailing end of the ink 4 filled in the ink containing tube 3 is filled with a follower 5 that advances as the ink 4 is consumed. 2) is a requirement.

According to claim 2, the spring locking projection 31
When the outer surface of the ink containing tube 3 is pressed and deformed to form the ink, even if the inner surface of the ink containing tube 3 is contracted and deformed by the pressing deformation, the ink 4 and the follower 5 are inside the ink containing tube 3. Since it is not filled, the ink 4 and the follower 5 are not pushed out by the movement of the ink 4.

[3] In the third invention of the present application, after the spring locking projection 31 is formed on the outer surface of the ink containing tube 3 made of synthetic resin by pressure deformation, the ink 4 is filled in the ink containing tube 3. Then, the front end of the ink 4 filled in the ink containing tube 3 is located at the front end opening of the ink containing tube 3, and then the pen tip 2 is press-fitted and fixed to the front end opening of the ink containing tube 3. The method of manufacturing the refill 1 for a retractable ballpoint pen (claim 3) is a requirement.

According to claim 3, the spring locking projection 31
When the outer surface of the ink containing tube 3 is pressed and deformed to form the ink, the ink 4 is not filled in the ink containing tube 3 even if the inner surface of the ink containing tube 3 is deformed by the pressing deformation. Therefore, there is no possibility that the ink 4 leaks due to the movement of the ink 4.

In addition, according to claim 3, the ink containing tube 3
After the ink 4 is filled in the inside, the front end of the filled ink 4 is located at the front end opening of the ink containing tube 3 which is a portion for press-fitting and fixing the pen tip 2. The ink 4 located at the front end opening of the ink storage tube 3 functions as a lubricant when the pen tip 2 is press-fitted, and the pen tip 2 can be smoothly pressed into the front end opening of the ink storage tube 3. . Therefore, it is not necessary to provide a special process for smooth press-fitting of the pen tip 2, and the manufacturing cost can be reduced.

[4] In the fourth invention of the present application, after the spring locking projection 31 is formed on the outer surface of the ink containing tube 3 made of synthetic resin by pressure deformation, the ink 4 is filled in the ink containing tube 3. Then, the front end of the ink 4 filled in the ink containing tube 3 is positioned at the front end opening of the ink containing tube 3, and then the pen tip 2 is press-fitted and fixed to the front end opening of the ink containing tube 3. Thereafter, a retractable ball-point pen refill 1 is formed by filling a follower 5 that advances with the consumption of the ink 4 from the rear end opening of the ink storage tube 3 to the rear end of the ink 4 in the ink storage tube 3. The manufacturing method (claim 4) is required.

According to claim 4, the spring locking projection 31
When the outer surface of the ink containing tube 3 is pressed and deformed to form the ink, even if the inner surface of the ink containing tube 3 is contracted and deformed by the pressing deformation, the ink 4 and the follower 5 are inside the ink containing tube 3. Since it is not filled, the ink 4 and the follower 5 are not pushed out by the movement of the ink 4.

Further, according to claim 4, the ink containing tube 3
After the ink 4 is filled in the inside, the front end of the filled ink 4 is located at the front end opening of the ink containing tube 3 which is a portion where the pen tip 2 is press-fitted and fixed. The ink 4 located at the front end opening of the ink storage tube 3 functions as a lubricant when the pen tip 2 is press-fitted, and the pen tip 2 can be smoothly pressed into the front end opening of the ink storage tube 3. . Therefore, it is not necessary to provide a special process for smooth press-fitting of the pen tip 2, and the manufacturing cost can be reduced.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the drawings. (See FIGS. 1 and 2)

FIG. 1 shows an embodiment of a method of manufacturing a refill 1 for a retractable ballpoint pen according to the present invention. The manufacturing process is shown in FIG. 1 (a) and FIG. 1 (b) from the upper diagram to the lower diagram. , FIG. 1 (c), FIG. 1 (d), FIG. 1 (e), and FIG. 1 (f).

[State of FIG. 1 (a)] FIGS. 1 (a) and 2
The initial state of the ink containing tube 3 is shown in (a). The ink containing tube 3 is made of a synthetic resin (for example, polypropylene resin) extruded body, and is a cylindrical body having an outer diameter of 3 mm and an inner diameter of 1.7 mm with both ends opened.

[State of FIG. 1 (b)] FIGS. 1 (b) and 2
(B) shows a state after the spring locking projection 31 is formed. A part of the outer surface of the ink containing tube 3 in the state shown in FIG. 1 (a) is pressed and deformed so as to be sandwiched by a pressing tool. As a result, a pair of flat spring locking protrusions 31 are formed at opposite positions on the outer surface of the ink containing tube 3. The inner surface of the ink containing tube 3 having the spring locking projection 31 is reduced in diameter from a circular cross section to an elliptical shape by pressure deformation, and the cross sectional area of the cross section of the space in the ink containing tube 3 is reduced. Is smaller than before pressing deformation.

[State of FIG. 1 (c)] FIG. 1 (c) shows a state in which the ink 4 is filled. The inclined outer surface of the metal-made tapered filling nozzle 6 is brought into pressure contact with the inner peripheral edge portion 32 of the front end opening of the ink containing tube 3 in the state of FIG. 1B, and the tip of the filling nozzle 6 is fixed. The ink containing tube 3
The ink is filled in the ink containing tube 3 from the filling nozzle 6 at the front end opening. Thereby, the front end of the ink 4 filled in the ink containing tube 3 is positioned at the front end opening of the ink containing tube 3. The ink 4 is preferably a water-based ink (specifically, a water-based ink having a shear thinning property), but may be an oil-based ink.

At the time of ink filling, since the inclined outer surface of the filling nozzle 6 is in pressure contact with the inner peripheral edge portion 32 of the front end opening of the ink containing tube 3, the ink is contained between the ink containing tube 3 and the filling nozzle 6. Even if the position shift occurs, the inner peripheral edge portion 32 of the front end opening of the ink containing tube 3 is guided by the outer surface of the inclined surface, so that the inner peripheral edge portion 32 of the front end opening of the ink containing tube 3 can be securely pressed. Is possible. Further, during ink filling, the tip of the filling nozzle 6 is located at the front end opening of the ink containing tube 3 into which the pen tip 2 is press fitted, and is not deeply inserted inward from the front end opening of the ink containing tube 3. For,
Even if the inner diameter of the ink containing tube 3 is as small as 2 mm or less, the tip of the filling nozzle 6 is not likely to bend,
A stable ink filling process without defective filling can be obtained.

[State of FIG. 1 (d)] FIG. 1 (d) shows a state immediately before the pen tip 2 is press-fitted. By the pressure contact of the filling nozzle 6 shown in FIG. 1C, the inner peripheral edge portion 32 of the front end opening of the ink containing tube 3 is pressed and deformed to form a conical inner surface, and at the same time, the nib 2 Is filled in the front end opening of the ink containing tube 3 which is a portion to be press-fitted and fixed.
The front end of is located. Therefore, when the pen tip 2 is press-fitted into the front end opening of the ink containing tube 3, the pen tip 2 does not catch on the inner peripheral edge portion 32 of the front end opening of the ink containing tube 3, and the front end of the ink containing tube 3 is The ink 4 present in the opening functions as a lubricant with the outer surface of the pen tip 2. As a result, the press-fitting of the pen tip 2 into the ink containing tube 3 becomes smooth, and there is no risk of defective press-fitting of the pen tip 2 (for example, incomplete press-fitting or damage to the press-fitting portion).

Further, a special manufacturing process for facilitating the press-fitting of the pen tip 2 into the ink containing tube 3 (for example, the outer surface of the conical surface of the pressing pin is the inner peripheral edge portion 3 of the ink containing tube 3).
It is not necessary to provide a step of press-contacting 2 and a step of applying a lubricant to the outer surface of the pen nib 2, the number of manufacturing steps is not increased, and the manufacturing cost can be kept low.

The pen tip 2 of the present embodiment holds a ball-point pen tip 21 made of metal (for example, made of stainless steel) having a ball rotatably held at its tip and an outer surface of the rear portion of the ball-point pen tip 21. The pen tip holder 22 is made of synthetic resin (made of polypropylene resin), and the outer surface of the pen tip holder 22 made of synthetic resin and the inner surface of the ink containing tube 3 made of synthetic resin are press-fitted and fixed. The pen holder 22 made of synthetic resin is used as the ink container 3 made of synthetic resin.
In the case of press-fitting in, the pen-tip holder 22 is deformed and the press-fitting defect is more likely to occur as compared with the case where a metal ball-point pen tip or a metal pen-tip holder is press-fitted in the synthetic resin ink containing tube 3. By the ink filling method of FIG. 1 (c), it is possible to sufficiently prevent press-fitting defects.

In addition to this, the pen tip 2 of the present invention may have a structure of only a metal or synthetic resin ball-point pen tip 21 having a ball rotatably held at its tip. In that case, the ball-point pen tip is used. 21 and outer surface of the ink container 3
It is press-fitted and fixed to the inner surface of the. In the ballpoint pen tip 21 of the present embodiment, the ball receiving seat is made of metal (for example,
Although it is formed by inwardly pressing and deforming the end of a thin tube made of stainless steel), the ball receiving seat may be formed by cutting a metal material.

[State of FIG. 1 (e)] FIG. 1 (e) shows a state immediately after the pen tip 2 is press-fitted and fixed. FIG. 1 (d)
When the press-fitting and fixing of the pen tip 2 and the ink containing tube 3 is completed from the state shown in Fig. 2, the outer surface of the pen tip 2 and the inner surface of the front end opening of the ink containing tube 3 are in close contact with each other in a ring shape, and the leakage of the ink 4 Is prevented. Further, the inner diameter and the outer diameter of the ink containing tube 3 are slightly increased by press-fitting the pen tip 2.

[State of FIG. 1 (f)] FIG. 1 (f) shows a state after the follower 5 is filled. The follower 5 is made of a high-viscosity fluid, is filled from the rear end opening of the ink containing tube 3 in the state shown in FIG. 1 (e), and is arranged at the rear end of the ink 4 in the ink containing tube 3. It Then, the ink 4 and the follower 5 are moved forward by the centrifugal force, and at the same time, the residual air inside the pen tip 2, the residual air in the ink 4, and the residual air in the follower 5 are transferred to the ink storage tube 3. The retractable ball-point pen refill 1 is removed from the rear-end opening, and is thus ready for writing. The follower 5 may be a high-viscosity fluid only, a high-viscosity fluid containing a solid substance, or a slide stopper made of an elastic material.

[0028]

According to the present invention, when the outer surface of the ink containing tube is pressed and deformed to form the spring locking projection,
Even if the inner surface of the ink containing pipe is contracted and deformed, the ink is prevented from leaking due to the movement of the ink because the ink is not filled inside the ink containing pipe.

According to the second aspect, when the outer surface of the ink containing tube is pressed and deformed to form the spring locking protrusion, even if the inner surface of the ink containing tube is contracted and deformed, the inside of the ink containing tube is not deformed. Since the ink and the follower are not filled, it is possible to prevent the ink and the follower from being pushed out by the movement of the ink.

According to the third aspect of the invention, when the outer surface of the ink containing tube is pressed and deformed to form the spring locking projection, even if the inner surface of the ink containing tube is contracted and deformed, the inside of the ink containing tube is not deformed. Since the ink is not filled, it is possible to prevent the ink from leaking due to the movement of the ink. Further, the pen tip can be smoothly press-fitted into the front end opening portion of the ink containing tube, and it is not necessary to provide a special step for smooth press-fitting of the pen tip, and the manufacturing cost can be reduced.

According to the present invention, when the outer surface of the ink containing tube is pressed and deformed to form the spring locking projection, even if the inner surface of the ink containing tube is contracted and deformed, the inside of the ink containing tube is not deformed. Since the ink and the follower are not filled, it is possible to prevent the ink and the follower from being pushed out by the movement of the ink. Further, the pen tip can be smoothly press-fitted into the front end opening portion of the ink containing tube, and it is not necessary to provide a special step for smooth press-fitting of the pen tip, and the manufacturing cost can be reduced.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

2A is an enlarged sectional view taken along the line AA of FIG. 1A, and FIG. 2B is an enlarged sectional view taken along the line BB of FIG. 1B.

[Explanation of symbols]

1 Retractable ballpoint pen refill 2 Nib 21 Ballpoint pen tip 22 Pen tip holder 3 Ink storage tube 31 Spring locking protrusion 32 Inner peripheral edge 4 ink 5 Follower 6 filling nozzles

Claims (4)

[Claims] 1. A method for producing a retractable ballpoint pen refill, comprising forming a spring locking projection on an outer surface of an ink containing tube made of synthetic resin by pressure deformation and then filling the ink into the ink containing tube. 2. An ink containing tube made of synthetic resin is formed with a spring locking projection on the outer surface thereof by pressing and deforming, and then the ink is filled into the ink containing tube, and thereafter the ink filled in the ink containing tube is filled. A method for producing a refill for a retractable ballpoint pen, comprising a trailing end filled with a follower that advances as the ink is consumed. 3. An ink containing tube made of synthetic resin is formed with a spring locking projection on the outer surface thereof by pressing and deforming, and then the ink is filled in the ink containing tube, and the front end of the ink filled in the ink containing tube is A method for producing a retractable ballpoint pen refill, which is located at a front end opening of an ink containing tube, and then a pen tip is press-fitted and fixed to the front end opening of the ink containing tube. 4. A spring locking projection is formed on the outer surface of an ink containing tube made of synthetic resin by pressure deformation, and then ink is filled into the ink containing tube, and the front end of the ink filled in the ink containing tube is It is positioned at the front end opening of the ink containing tube, and then the pen tip is press-fitted and fixed to the front end opening of the ink containing tube, and then the ink in the ink containing tube is inserted from the rear end opening of the ink containing tube. A method for producing a retractable ball-point pen refill, the end of which is filled with a follower that advances as the ink is consumed.