WO2015012203A1

WO2015012203A1 - Ballpoint pen

Info

Publication number: WO2015012203A1
Application number: PCT/JP2014/069128
Authority: WO
Inventors: 安永　雅博; 中谷　泰範
Original assignee: 株式会社サクラクレパス
Priority date: 2013-07-23
Filing date: 2014-07-18
Publication date: 2015-01-29
Also published as: JPWO2015012203A1

Abstract

[Problem] To provide, simply and inexpensively, a ballpoint pen in which ink does not easily leak to the outside even when the ink is under constant pressure, and in which large amounts of ink are not wasted. [Solution] The present invention is configured by being provided with a shaft (10) for a user to grasp, an application liquid accommodation part (20) to be filed with ink, a ballpoint pen tip (4), application liquid supply paths (25, 26) for supplying the ink accommodated in the application liquid accommodation part (20) to the ballpoint pen tip (4), and a liquid pressurizing means for pressurizing the ink toward the ballpoint pen tip (4) side. The liquid pressurizing means is provided with a pressing piece (12) and a spring (13) for urging the pressing piece (12). Furthermore, an inner space (24) of the application liquid accommodation part (20) and the application liquid supply paths (25, 26) of smaller diameter than the inner space (24) are integrally formed inside the shaft (10), and the ballpoint pen tip (4) is integrally attached to a tip part of the application liquid supply paths (25, 26). In addition, a cylindrical decorative member (11) is attached to the outside of the application liquid supply paths (25, 26).

Description

Ballpoint pen

The present invention relates to a ball-point pen, and more particularly to a ball-point pen that can easily discharge ink even when high-viscosity ink is employed.

Conventionally, applicators for decorating various items such as photographs, pottery, shirts, etc. in addition to small items such as mobile phones, hand-held mirrors, stationery, etc. are known. This type of applicator generally employs high-viscosity ink. When a letter or design is drawn by handwriting, the drawn letter or design is rounded and raised.

However, when the viscosity of the ink is increased, it becomes difficult to smoothly discharge the ink. That is, high-viscosity ink is difficult to flow and easily clogs. Therefore, if the ink is discharged from an opening having a small diameter for fine application, the ink may not stably flow out.

As a measure for solving such a problem, there is a ballpoint pen disclosed in Patent Document 1.
The ballpoint pen of Patent Document 1 proposed by the applicant of the present application is one within a predetermined range that exerts advantageous effects on the ball size, the size of the ball house, the width of the arrow groove, etc. Thus, even a highly viscous ink can be stably discharged. Furthermore, the ballpoint pen disclosed in Patent Document 1 can smoothly flow out even if it is a highly viscous ink containing a bright pigment with large particles.

JP 2012-131079 A

However, the ballpoint pen of Patent Document 1 has room for improvement from the viewpoint of stabilizing the outflow of ink.

Therefore, the present inventors considered to pressurize the ink at the time of use to stabilize the outflow of the ink. Then, a liquid pen was provided inside the ink tank, and a ball-point pen that pressurizes the ink toward the pen tip side was made as a prototype.

More specifically, as shown in FIG. 10, ink is directly filled into the shaft cylinder 102, a pressing piece 112 behind the portion filled with ink, and the pressing piece 112 toward the pen tip side. A ballpoint pen 100 provided with a spring 113 for biasing was manufactured.

In this ballpoint pen 100, a shaft cylinder 102 extending from the rear end portion of the pen shaft to the pen tip is integrally formed. That is, unlike the shaft tube 202 formed by connecting the pen tip side member 220 and the pen shaft side member 221 as shown in FIG. 11, the shaft tube 102 of the ballpoint pen 100 has a pen shaft rear end. It extends without gaps from the part to the pen tip. As a result, the ink is hardly leaked even when the ink is constantly pressurized.

That is, in the configuration in which the ink is constantly pressurized, the ink tends to flow from the accommodated portion to the outside. For this reason, when a gap is formed on the side of the pen shaft, the ink leaks out from the gap unless the gap is sealed in a liquid-tight state.
However, if the gap formed on the side of the pen shaft is sealed in a liquid-tight state, the structure becomes complicated, and a sealing member is required, resulting in an increase in manufacturing cost.

Therefore, as shown in FIG. 10, the present inventors integrally formed the shaft tube 102 and sealed the side of the portion containing the ink in a liquid-tight state. Thus, leakage of ink could be prevented by a structure that can be manufactured relatively easily and inexpensively.

However, this prototype ballpoint pen 100 has a problem that if it is continuously used, a lot of ink remains in the shaft cylinder 102 and is wasted.
This will be specifically described below.

When the ink is reduced by continuously using the ballpoint pen 100, the pressing piece 112 moves toward the pen tip side as the ink decreases. In other words, the state shifts from the state in which the pressing piece 112 is positioned rearward (the state shown in FIG. 10A) to the state in which the pressing piece 112 is close to the vicinity of the pen tip (the state shown in FIG. 10B). To do.

Here, the inner diameter lx on the rear end side of the shaft tube 102 is longer than the inner diameter in the region 130 on the front end side of the shaft tube 102. The maximum diameter of the pressing piece 112 is substantially the same as the inner diameter lx on the rear end side of the shaft tube 102.

Therefore, even when the pressing piece 112 moves to the pen tip side, the maximum diameter portion of the pressing piece 112 cannot enter the region 130 on the front end side of the shaft tube 102 as shown in FIG. . In other words, the pressing piece 112 has a structure that cannot move to the pen tip side from a predetermined portion.

By the way, as described above, the ink used in the prototype ballpoint pen 100 is a high-viscosity ink and needs to be pressed by the pressing piece 112 in order to stably flow out.
However, if the pressing piece 112 cannot move to the pen tip side from a predetermined portion, the ink stored in the area 130 on the front end side of the shaft tube 102 cannot be pressed. Therefore, the ink stored in the area 130 on the front end side cannot be stably discharged, and in some cases, all the ink stored in the area 130 remains inside the shaft cylinder 102. Then, the ink stored in this region 130 cannot be used for writing and is wasted.

In view of the above-described problems of the prior art, it is an object of the present invention to provide a ballpoint pen that does not easily leak to the outside even when the ink is constantly pressurized and does not waste a large amount of ink, simply and inexpensively. .

The invention according to claim 1 for solving the above-described problem is a shaft cylinder for a user to hold, a coating liquid storage section capable of filling the coating liquid, a ballpoint pen tip for coating the coating liquid, In a ballpoint pen having a coating solution supply path for supplying the coating solution stored in the coating solution storage unit to the ballpoint pen tip, the device includes a liquid pressurizing unit for pressurizing the coating solution toward the ballpoint pen tip, The liquid pressurizing means includes at least a pressing piece and a biasing member that biases the pressing piece toward the ballpoint pen tip, and the interior of the shaft tube includes an internal space of the coating liquid storage unit, The coating liquid supply path having a narrower diameter than the internal space is integrally formed, and the ballpoint pen tip is integrally attached to a tip portion of the coating liquid supply path, and a cylindrical shape is formed outside the coating liquid supply path. make up A ballpoint pen, characterized in that wood is mounted.

In the present invention, a coating liquid storage section for storing the coating liquid inside the shaft cylinder for the user to hold, and a coating liquid for supplying the coating liquid stored in the coating liquid storage section to the ballpoint pen tip The supply path is integrally formed. That is, the coating liquid storage part and the coating liquid supply path located between the coating liquid storage part and the ball-point pen chip are integrally formed. As a result, the portion located on the side of the shaft tube can be closed in a liquid-tight state easily and inexpensively from the coating liquid storage portion to the pen tip portion where the ballpoint pen tip is located. That is, by forming the coating liquid storage part and the coating liquid supply path integrally, these inner peripheral surfaces can be easily and inexpensively continuous without a gap.
Furthermore, in the present invention, the coating liquid supply path has a narrower diameter than the coating liquid container. In other words, the coating liquid supply path is narrower than the coating liquid container, and a large amount of ink cannot be stored in the coating liquid supply path. That is, since a large amount of ink does not remain inside the coating liquid supply path through which the pressing piece cannot enter, it is possible to reduce the amount of ink that cannot be used for writing.

By the way, if the coating liquid storage part and the coating liquid supply path are integrally formed inside the shaft tube for the user to hold, and the coating liquid supply path is narrower than the coating liquid storage part, it is inevitably necessary to use a ballpoint pen. The front side becomes thinner. Here, some users hold and use the vicinity of the tip of the ballpoint pen. And such a user will become difficult to use a ball-point pen, if the pen tip vicinity of a ball-point pen becomes thin.

Therefore, in the present invention, a cylindrical decorative member is attached to the outside of the coating liquid supply path, that is, the outside of the narrowed portion on the pen tip side. Thereby, even if the coating liquid supply path is narrowed, the thickness in the radial direction on the pen tip side can be increased, so that it is possible to provide a ballpoint pen that is easy to hold and use by the user.

The invention according to claim 2 is characterized in that the internal space of the coating liquid storage part and the coating liquid supply path having a narrower diameter than the internal space are continuous through a step. 1 is a ballpoint pen.

According to such a configuration, the internal space of the coating liquid container and the coating liquid supply path having a narrower diameter than the internal space are continuous through the step. That is, the coating liquid supply path is further narrowed, and the coating liquid supply path has a structure that can store only a small amount of ink. That is, the amount of ink remaining in the coating liquid supply path can be further reduced.

In the present invention, the maximum diameter of the internal space of the coating liquid container is preferably 5.0 mm or more and 11.0 mm or less, and the maximum diameter of the coating liquid supply path is preferably 1.0 mm or more and 5.0 mm or less ( Claim 3).

According to the present invention, it is possible to easily and inexpensively provide a ball-point pen that does not easily leak ink to the outside even when the ink is constantly pressurized and does not waste a large amount of ink.

It is a perspective view which shows the ball-point pen which concerns on embodiment of this invention, and shows the state which removed the cap. It is a disassembled perspective view which shows the ball-point pen main body of FIG. It is a side view which shows the pen axis | shaft formation part of FIG. It is sectional drawing which shows the pen axis | shaft formation part of FIG. It is a side view which shows the spring of FIG. 2, and is partially expanded and shown. It is a figure which shows the spring of FIG. 5, (a) is a front view, (b) shows a rear view. It is a figure which shows the tail plug of FIG. 2, (a) is a perspective view, (b) shows the perspective view which fractured | ruptured a part of (a). It is sectional drawing which shows the ball-point pen main body of FIG. 1, and shows the state which filled the ink tank formation part with ink. It is sectional drawing which shows the ball-point pen main body of FIG. 1, and shows the state by which the ink is not stored by the ink tank formation part. It is sectional drawing which shows the ball-point pen which the present inventors made as an experiment, (a) shows the state before using, (b) shows the state after using it continuously. It is sectional drawing which shows the pen point part in the ballpoint pen of a prior art.

Hereinafter, embodiments of the present invention will be described. In the following description, the “front-rear” relationship will be described with the pen tip side as the front side.

As shown in FIG. 1, the ballpoint pen 1 according to the embodiment of the present invention includes a cap 2 and a ballpoint pen body 3. That is, when the ball-point pen main body 3 is not used, the cap 2 is attached to prevent the ink (coating liquid, indicated by G in each figure) from drying at the tip of the ball-point pen tip 4.
In addition, in the ball-point pen 1 of this embodiment, the highly viscous ink containing the luster pigment with a big particle is employ | adopted.

As shown in FIG. 2, the ballpoint pen body 3 includes a pen shaft forming portion 10 (shaft tube), a pen tip forming portion 11 (decorating member), a pressing piece 12, a spring 13 (biasing member), and a tail plug 14. It has a configuration.

As shown in FIG. 3, the pen shaft forming portion 10 has a substantially cylindrical outer shape and has a structure in which the diameter of each portion in the longitudinal direction is different. That is, the pen shaft forming portion 10 includes an ink tank forming portion 20 (coating liquid storage portion) having the largest diameter, a connecting portion 21 having a smaller diameter than the ink tank forming portion 20, and a diameter that is further larger than the connecting portion 21. And a small chip mounting portion 22. Then, the ink tank forming part 20, the connecting part 21, and the chip attaching part 22 are successively arranged from the rear end side to the front end side of the pen shaft forming part 10.

The ink tank forming part 20, the connecting part 21, and the chip mounting part 22 are all substantially cylindrical and have the same central axis. For this reason, a step is formed on the outer peripheral surface of the pen shaft forming portion 10 at a portion where the ink tank forming portion 20 and the connecting portion 21 are connected and a portion where the connecting portion 21 and the tip mounting portion 22 are connected. Has been. That is, the ink tank forming part 20 and the connecting part 21, and the connecting part 21 and the chip attaching part 22 are in a continuous state via steps.

And also in the inside of the pen axis | shaft formation part 10, as FIG. 4 shows, three space from which a diameter differs is continuing. That is, the storage space 24 located inside the ink tank forming part 20, the first flow path forming space 25 (coating liquid supply path) located inside the most rear part of the connecting part 21, and the connecting part 21 A part of the front side and the second flow path forming space 26 (coating liquid supply path) located inside the chip mounting portion 22 are also continuous.
The storage space 24, the first flow path forming space 25, and the second flow path forming space 26 communicate with each other to form an in-axis space 27 that is an integral space. The in-shaft space 27 is also a through hole that extends from the rear end to the front end of the pen shaft forming portion 10.

Specifically, the axial space 27 is a space whose inner diameter becomes smaller toward the front end side. That is, the first flow path forming space 25 is shorter in the radial direction (vertical direction in FIG. 4) than the storage space 24, and the second flow path forming space 26 is formed in the first flow path forming space 26. The length in the radial direction is further shorter than the space 25.

A step is formed in a portion that becomes a boundary between the storage space 24 and the first flow path forming space 25 and a portion that becomes a boundary between the first flow path forming space 25 and the second flow path forming space 26. Yes. That is, the storage space 24, the first flow path forming space 25, and the second flow path forming space 26 are continuous through steps.

That is, on the inner peripheral surface of the inner space 27, a plurality of portions having different inner diameters are continuous through a step in the longitudinal direction, and the diameter gradually decreases toward the front.

Here, the ballpoint pen tip 4 is integrally attached to the tip attaching portion 22. The front end portion of the ball-point pen tip 4 is in a state of protruding forward from the front end opening of the tip mounting portion 22, that is, the front end opening of the in-axis space 27. On the other hand, the rear end portion of the ball-point pen tip 4 is located inside the second flow path forming space 26. And the inner peripheral surface of the chip | tip attachment part 22 and the outer peripheral surface of the ball-point pen chip | tip 4 are in the state closely_contact | adhered liquid-tightly.

Incidentally, as will be described in detail later, the storage space 24 that is an internal space of the ink tank forming portion 20 is a portion that functions as an ink tank that is filled with ink when in use. And the 1st flow path formation space 25 and the 2nd flow path formation space 26 which are the space formed in the inside of the connection part 21 and the chip | tip attachment part 22 are the ink with which the ink tank (storage space 24) was filled. It is a part that functions as an ink supply channel (coating liquid supply channel) for supplying the ball-point pen chip 4.

That is, the pen shaft forming portion 10 is a portion that becomes a pen shaft, a portion that functions as an ink tank, a portion that functions as an ink supply channel, and a portion to which the ballpoint pen tip 4 is attached. In other words, in the ballpoint pen 1 of the present embodiment, the ink tank, the ink supply flow path, and the portion for fixing the ballpoint pen tip 4 are integrally formed. The integrally formed portion is a pen shaft portion, that is, a portion directly held by the user's hand.
Since the pen shaft forming portion 10 is integrally formed, the inner periphery of the pen shaft forming portion 10 is the inner periphery of the storage space 24, the first flow path forming space 25, and the second flow path forming space 26. The surface is continuous without a gap along the longitudinal direction of the pen shaft forming portion 10.

As shown in FIG. 2, the pen tip forming portion 11 has a smaller diameter as the outer peripheral surface thereof moves toward the front end side. That is, the pen tip forming part 11 is a cylindrical member having a tapered outer peripheral surface.
Note that an annular protrusion (not shown) that protrudes inward is provided on the inner peripheral surface of the pen tip forming portion 11. From this, the pen tip forming part 11 can be externally fitted and fixed to a narrow-diameter portion (the connecting part 21 and the tip attaching part 22) located on the front end side of the pen shaft forming part 10. . That is, an annular protrusion (not shown) formed on the inner peripheral surface of the pen tip forming portion 11 and a protrusion (not shown) formed on the outer peripheral surface of the narrow-diameter portion of the pen shaft forming portion 10 are engaged. It has a structure that can be fixed integrally.

The pressing piece 12 is a substantially bottomed cylindrical member whose rear end side is opened (the open portion on the rear end side is not shown in FIG. 2). Further, the front end surface of the pressing piece 12 is rounded and convex toward the front.

The spring 13 is formed by winding a long and thin metal wire in a spiral shape with a gap like a coil spring.

Here, the spring 13 of this embodiment has a structure that does not form a so-called end turn. That is, at both ends in the longitudinal direction of the spring 13 in the natural state, a gap α is formed between adjacent portions in the longitudinal direction, as shown in FIG.
The natural state here is a state in which no external force is applied.

More specifically, in the natural state, the spring 13 is in a state in which a gap α is formed between adjacent portions in the longitudinal direction in all the regions from one end in the longitudinal direction to the other end. In other words, the spring 13 has no so-called tightly wound portion and has a structure in which the adjacent portions in the longitudinal direction do not come into contact with each other in the natural state.

From this, when paying attention to the first winding portion 13a of the spring 13 and the second winding portion 13b that is continuous with the first winding portion 13a, a part of the first winding portion 13a and a part thereof in the longitudinal direction A gap α is formed between a portion of the second portion 13b facing each other. Similarly, the second volume portion 13b and the third volume portion 13c, the third volume portion 13c and the fourth volume portion (numbering omitted), etc. A gap α is formed between them. That is, in the spring 13, a gap α is formed between adjacent portions in the longitudinal direction in any portion.

Further, as shown in FIG. 6, both end portions 13α and 13β of the spring 13 are bent toward the inner side in the radial direction, and are located inside the outer edges of the spring winding.
More specifically, both end portions 13α and 13β of the spring 13 are positioned inside the outer peripheral edge of the maximum diameter portion of the spring 13. Furthermore, in this embodiment, all are in the state located inside the inner peripheral edge of the maximum diameter portion of the spring 13.

As shown in FIG. 7, the tail plug 14 is a member having a substantially bottomed cylindrical shape, and a front end portion (a lower end portion in FIG. 7) is open to the outside.

On the outer peripheral surface of the tail plug 14, a flange portion 35 is provided in a portion located slightly forward of the rear end portion (a portion located slightly lower than the upper end portion in FIG. 7).
The flange portion 35 protrudes radially outward from the outer peripheral surface of the tail plug 14, and is a substantially annular plate-shaped portion that continues in an annular shape in the circumferential direction of the tail plug 14.

Furthermore, the rear end surface (upper end surface in FIG. 7) of the tail plug 14 is provided with a vent hole 36 communicating with the inside and outside at the center. That is, the vent hole 36 is a through hole that penetrates a disk-shaped portion that forms the rear end surface (the upper end surface in FIG. 7) of the tail plug 14 in the member thickness direction.

Subsequently, the internal structure of the tail plug 14 will be described.

As shown in FIG. 7B, inside the tail plug 14, a substantially cylindrical inner cylinder projects forward from the rear end surface of the internal space 37 (projects downward from the upper end surface in FIG. 7B). A portion 38 is formed.
Here, the air hole 36 formed in the rear end surface (the upper end surface in FIG. 7B) of the tail plug 14 is in a state of communicating with the inner space of the inner cylinder portion 38. Further, the inner space of the inner cylinder portion 38 is opened to the inner space 37 of the tail plug 14 at its front end portion (lower end portion in FIG. 7B).
That is, the tail plug 14 is in a state where the inside and outside communicate with each other through the air hole 36 formed in the rear end surface and the inner space of the inner cylinder portion 38.

Next, the assembly structure of the ballpoint pen 1 of this embodiment will be described in detail with reference to the drawings.

As shown in FIG. 8, ink is filled into the pen shaft forming portion 10, and further, a lubricant, a sealant, a backflow preventive agent and the like (parts indicated by

reference numerals

40 and 41 in the drawing, Hereinafter, it is simply referred to as a lubricant 40, 41).
Note that the lubricant, sealant, and backflow preventive agent do not necessarily need to contain three kinds of substances, and one kind of substance may serve two or more functions. For example, a silicone layer may be formed by inserting a so-called two-component silicone, and the silicone layer may function as a sealant and a backflow preventer.

Further, the pressing piece 12 and the spring 13 are inserted into the inner space 27 from the rear end side, and the tail plug 14 is attached to the rear end portion of the pen shaft forming portion 10. As a result, in the in-axis space 27 of the pen shaft forming portion 10, the ink, the

lubricants

40 and 41, the pressing piece 12, and the spring 13 are sequentially arranged from the front end side to the rear end side.
The

lubricants

40 and 41, the pressing piece 12, and the spring 13 function as a liquid pressurizing unit that constantly pressurizes ink when the ballpoint pen body 3 is used.

At this time, inside the pen shaft forming portion 10, the portion located behind the ink is sealed with a

lubricant

40, 41 and the outer peripheral surface of the ballpoint pen tip 4 and the inner peripheral surface of the tip mounting portion 22 are liquid-tight. The state is in close contact. Therefore, the space in which the ink is stored is in a state of being liquid-tightly sealed except for the tip side of the ballpoint pen tip 4.
Here, the pen shaft forming portion 10 of the present embodiment is integrally formed with a portion from the rear end of the pen shaft to the pen tip, and the side surface extends without a gap. For this reason, it is possible to seal the space in which the ink is stored in the liquid-tight state as described above without performing special processing on the side surface of the pen shaft. In other words, the pen shaft forming unit 10 of this embodiment simply seals the contact portion with the ballpoint pen tip 4 and the rear end portion of the ink in a liquid-tight state, and the space where the ink is stored is described above. Since it can be sealed in such a liquid-tight state, a space in which ink is stored can be easily and inexpensively sealed.

Further, the outer peripheral surface of the tail plug 14 is in contact with the inner peripheral surface of the pen shaft forming portion 10. That is, the front end portion of the tail plug 14 is positioned in front of the rear end portion of the pen shaft forming portion 10. The rear end portion of the spring 13 is in contact with the front end surface of the tail plug 14.
According to such a configuration, the amount of contraction of the spring 13 can be adjusted only by adjusting the insertion length of the tail plug 14 with respect to the pen shaft forming portion 10. Specifically, when the insertion length of the tail plug 14 is increased, the spring 13 is disposed in a more contracted state. On the other hand, when the insertion length of the tail plug 14 is shortened, the spring 13 is arranged in a longer extended state. That is, by setting it as the above-mentioned structure, the shrinkage | contraction amount and arrangement position of the spring 13 become easy.

In addition, the pen tip forming portion 11 is externally fitted to the front end side portion of the pen shaft forming portion 10 and is integrally attached. As a result, the ballpoint pen body 3 is completed.

In this way, by fitting the pen tip forming portion 11 to the front end side portion of the pen shaft forming portion 10, the radial thickness at the front end portion of the ballpoint pen body 3 can be increased.
Specifically, in the present embodiment, as shown in FIG. 4, the first flow path forming space 25 and the second flow path forming space 26 are sufficiently narrower than the storage space 24. Therefore, the part on the front end side of the pen tip shaft forming portion 10 is much thinner than the part on the rear end side. Here, if the vicinity of the tip of the main body of the ball-point pen body 3 becomes very thin (the connecting portion 21 and the tip mounting portion 22 are exposed), it becomes difficult for some users to grip the ball-point pen body 3. That is, it becomes difficult for a user who holds and uses the tip portion to be held when the tip portion becomes very thin.

Therefore, in the ballpoint pen body 3 of the present embodiment, the pen tip forming portion 11 is fitted on the pen shaft forming portion 10 to increase the radial thickness at the tip portion. This makes it possible to provide the ballpoint pen body 3 that is easy for the user to grip even if the first flow path forming space 25 and the second flow path forming space 26 are sufficiently narrowed.

Furthermore, the ballpoint pen 1 is completed by attaching a cap 2 formed separately to the ballpoint pen body 3 (see FIG. 1).

In the ballpoint pen 1 of the present embodiment, when writing is continued in a state where ink is filled (the state shown in FIG. 8), the ink decreases, and the pressing piece 12 moves to the pen tip side accordingly. (The state shown in FIG. 9 is obtained). At this time, the spring 13 also gradually extends from the greatly contracted state, and finally shifts to a slightly contracted state. Thus, the spring 13 presses the pressing piece 12 and the

lubricants

40 and 41 and pressurizes the ink through the pressing piece 12 and the

lubricants

40 and 41.

Here, the pressing piece 12 and the

lubricants

40 and 41 move only inside the ink tank forming part 20 and do not enter the connecting part 21 and the chip attaching part 22. Therefore, when the pressing piece 12 and the

lubricants

40 and 41 are closest to the pen tip side (the state shown in FIG. 9), these are located inside the ink tank forming portion 20.
From this, the pressing piece 12 and the

lubricants

40 and 41 cannot press the ink filled in the connecting portion 21 and the chip mounting portion 22, so that the ink is not inside the connecting portion 21 and the chip mounting portion 22. It will remain.

However, in this embodiment, the storage space 24 formed inside the ink tank forming portion 20 and the first flow path forming space 25 located inside the connecting portion 21 are continuous via a step. That is, the first flow path forming space 25 is sufficiently narrower than the storage space 24.
More specifically, the first flow path forming space 25 and the second flow path forming space 26 located between the ink tank forming portion 20 and the ballpoint pen tip 4 are sufficiently thinner than the ink tank forming portion 20. Therefore, a large amount of ink is not stored inside these. Therefore, even if ink remains in the first flow path forming space 25 and the second flow path forming space 26 that are the internal spaces of the connecting portion 21 and the chip mounting portion 22, the amount of remaining ink is small. A large amount of ink is not wasted.

More specifically, if the first flow path forming space 25 and the second flow path forming space 26 are too narrow than the storage space 24, ink cannot be stably supplied to the ballpoint pen tip 4. On the other hand, if the first flow path forming space 25 and the second flow path forming space 26 are made thick, a large amount of ink remains in these areas where the pressing pieces 12 and the like do not enter, which is not preferable.

Therefore, from the viewpoint of supplying ink stably and preventing a large amount of ink from remaining in the first flow path forming space 25 and the second flow path forming space 26, the length of the maximum diameter of the storage space 24 is set. L1 is preferably 5.0 millimeters or more and 11.0 millimeters or less, more preferably 6.0 millimeters or more and 10.0 millimeters or less, and even more preferably 8.04 millimeters.
Note that an error of about plus or minus 0.05 millimeters is allowed.

Similarly, the length L2 of the maximum diameter of the first flow path forming space 25 and the second flow path forming space 26 is preferably 1.0 millimeter or more and 5.0 millimeters or less, and more preferably 2.0 mm. It is not less than millimeters and not more than 4.0 millimeters, more preferably 3.1 millimeters.
Note that an error of about plus or minus 0.05 millimeters is allowed.

Similarly, the minimum diameter length L3 of the first flow path forming space 25 and the second flow path forming space 26 is preferably 0.5 millimeters or more and 2.3 millimeters or less, more preferably 0.7 millimeters. It is not less than millimeters and not more than 2.1 millimeters, more preferably 1.4 millimeters.
Note that an error of about plus or minus 0.05 millimeters is allowed.

That is, the maximum diameter length L2 of the first flow path forming space 25 and the second flow path forming space 26 is 20% to 45% of the maximum diameter length L1 of the storage space 24. It is more preferable that the length is about 38% of the length L1 of the maximum diameter of the storage space 24.
Note that an error of about plus or minus 3 percent is allowed.

Further, in the present embodiment, in the initial state where no ink is used (the state shown in FIG. 8), the spring 13 is contracted to a length of about a quarter of the natural state. Further, in a state where the ink in the ink tank forming portion 20 is completely used (the state shown in FIG. 9), the spring 13 is configured to be contracted to about one half of the natural state.
That is, the spring 13 is always contracted until the ink in the ink tank forming unit 20 is used up, and the ink is constantly pressurized.
Note that “about” a quarter length allows an error of about plus or minus 5 mm. The same is true for a length of about half.

In other words, when the spring 13 is most compressed when the ink is pressed, the spring 13 is contracted to a length of about a quarter. Further, when the spring 13 is most stretched when the ink is pressed, the spring 13 is contracted to a length of about one half.

In the state where the spring 13 is most compressed when the ink is pressed, in other words, in the most compressed state when the spring 13 is used (the state shown in FIG. 8), the length of the spring 13 in the radial direction is the spring 13. Is shorter than the length in the radial direction of the ink tank forming portion 20 for storing the ink. Therefore, a gap is formed between the outer edge portion in the radial direction of the spring 13 and the inner peripheral surface of the ink tank forming portion 20. As a result, the spring 13 does not come into contact with the inner peripheral surface of the ink tank forming portion 20.

1 Ball-point pen 4 Ball-point pen tip 10 Pen shaft forming part (shaft tube)
11 Nib forming part (decorative member)
12 Pressing piece 13 Spring (biasing member)
20 Ink tank formation part (coating liquid storage part)
25 1st flow path formation space (coating liquid supply path)
26 Second channel formation space (coating liquid supply path)

Claims

A shaft cylinder for a user to hold, a coating liquid storage part that can be filled with a coating liquid, a ballpoint pen tip for coating the coating liquid, and a coating liquid stored in the coating liquid storage part to the ballpoint pen tip In a ballpoint pen with a coating liquid supply path for supplying,
Having a liquid pressurizing means for pressurizing the coating liquid toward the ballpoint pen tip,
The liquid pressurizing means includes at least a pressing piece, and an urging member that urges the pressing piece toward the ballpoint pen tip,
An internal space of the coating liquid container and the coating liquid supply path having a narrower diameter than the internal space are integrally formed inside the shaft cylinder, and the ball-point pen tip is disposed at a tip portion of the coating liquid supply path. Are attached together,
A ballpoint pen, wherein a cylindrical decorative member is attached to the outside of the coating liquid supply path.
2. The ballpoint pen according to claim 1, wherein an internal space of the coating liquid container and the coating liquid supply path having a narrower diameter than the internal space are continuous through a step.
The maximum diameter of the internal space of the coating liquid storage unit is 5.0 mm or more and 11.0 mm or less, and the maximum diameter of the coating liquid supply path is 1.0 mm or more and 5.0 mm or less. Or the ball-point pen of 2.