JP4408651B2

JP4408651B2 - Cap-type writing instrument

Info

Publication number: JP4408651B2
Application number: JP2003151759A
Authority: JP
Inventors: 徳男守山
Original assignee: Pilot Corp KK
Current assignee: Pilot Corp KK
Priority date: 2003-05-29
Filing date: 2003-05-29
Publication date: 2010-02-03
Anticipated expiration: 2023-05-29
Also published as: JP2004351728A

Description

【０００１】
【発明の属する技術分野】
本発明は、軸筒にキャップを着脱自在に装着してなるキャップ式筆記具に関する。
【０００２】
【従来の技術】
従来から、軸筒の外壁に形成した突部と、該突部に対向するキャップの内壁に形成した凸部とが、乗り越し嵌合することにより、軸筒にキャップを着脱自在に装着してなるキャップ式筆記具はよく知られている。また、軸筒の把持部に弾性体を装着し、この弾性体を被覆するようにキャップを装着してなるキャップ式筆記具もよく知られいて、特開２００１−３２８３９２号「筆記具」にて開示されている。
【０００３】
こうしたキャップ式筆記具は、軸筒とキャップを乗り越し嵌合するだけでなく、軸筒の把持部に装着した弾性体より後端側の軸筒に、段部や突起部を形成し、この段部や突起部の外径を、キャップの開口部の内径より大きくして、圧入嵌合することにより、キャップが軸筒に対して横ぶれを起こさないようにするとともに、軸筒とキャップの乗り越し嵌合の補助的な役割も果たしている。また、段部や突起部が周状に連続的に形成してあれば、キャップ内の気密性も確保できる。
【０００４】
【特許文献１】
「特開２００１−３２８３９２号公報」
【０００５】
【発明が解決しようとする課題】
しかし、従来の低価格のキャップ式筆記具は、軸筒及び／又はキャップを樹脂材料で形成しているため、繰り返しキャップの着脱を行うため、経時によって、軸筒の外壁に形成した突部と、キャップの内壁に形成した凸部が擦り減る等、寸法変化が生じやすく、その結果、軸筒とキャップの嵌合力の低下してしまう恐れがあった。同様に、キャップの内壁及び軸筒の突起部も経時により寸法変化が生じ、圧入力も低下するため、嵌合力の低下を防止しにくく、気密性も低下する。
【０００６】
そのため、軸筒とキャップが圧入力を増加するため、ラップする部分を多く設定し、経時による寸法変化が起こっても、キャップ内部の気密性を確保することも考えらるが、初期の軸筒へのキャップの装着性が著しく低下するとともに、酷い場合には、軸筒及び／又はキャップにひび割れが発生してしまう恐れがあった。
【０００７】
本発明は上記問題を鑑み、経時により寸法が変化しにくく、軸筒とキャップの嵌合力の低下、及びキャップ内の気密性が低下しにくいキャップ式筆記具を提供するものである。
【０００８】
【課題を解決するための手段】
前記目的を達成するために本発明では、把持部に弾性体からなるグリップ部材を装着してなる軸筒の外壁に形成した突部と、該突部に対向するキャップの内壁に形成した凸部とが、乗り越し嵌合することにより、軸筒の把持部を覆うようにキャップを着脱自在に装着してなるキャップ式筆記具において、前記グリップ部材の後端部に、対向するキャップの開口部の内径より大径とした膨出部を形成し、前記軸筒の外壁に形成した突部が、前記グリップ部材に形成した窓部から突出するとともに、前記突部と、キャップの内壁に形成した凸部が、乗り越し嵌合を開始した後、前記膨出部にキャップの開口部の内壁が当接し、前記乗り越し嵌合を終了と同時に圧入嵌合も終了し、前記キャップが前記グリップ部材を覆うことを特徴する。
【０００９】
また、前記窓部が、前記グリップ部材の後端部に形成した膨出部の近傍に形成してあることを特徴とする。
【００１０】
本発明のグリップ部材は、弾性変形可能なシリコーンゴム、天然ゴム、ブチルゴム、フッ素ゴム、塩化ビニル樹脂、ブタジエンゴム、ウレタンゴム、ポリエチレン樹脂、その他合成ゴム、熱可塑性エラストマー等、筆記具のグリップ部材として一般的に知られている弾性体のなかから適宜選定すればよい。
【００１１】
【発明の実施の形態】
本発明の実施の形態を、図面を用いて説明する。
図１から図３に示すキャップ式筆記具１は、図示はしていないが、インキ収容筒９の先端部に、ボールを回転自在に抱持したボールペンチップからなるペン先部１１を、チップホルダー１０を介して装着したボールペンレフィルを軸筒５内に収容してある。キャップ２には、ペン先部１１の先端を密閉する弾性体４を配設し、軸筒５の外壁に形成した複数の突部６と、キャップ２の内壁に形成した周状の凸部２ｂを乗り越し嵌合することにより、軸筒５に対し、キャップ２を着脱自在に装着してなるキャップ式の筆記具である。キャップ２にはクリップ３が一体に形成してある。
【００１２】
軸筒５の把持部５ａは、他の軸筒より小径に形成してあり、この小把持部５ｂに弾性体からなるグリップ部材７を装着してある。この時、グリップ部材７を軸筒５に装着した状態で、グリップ部材７の後端部に、キャップ２の開口部２ａの内径Ｍより大きい外径Ｍを有する膨出部８が形成されるように、把持部５ａの後端部に突状部５ｂを形成してある。また、膨出部８以外のグリップ部材の外径は、キャップの開口部２ａの内径Ｍより小径に形成してある。
【００１３】
また、軸筒５の外壁に形成した複数の突部６は、グリップ部材７の後端部に形成した窓部７ａから突出させることにより、キャップ２の内壁に形成した複数の凸部２ｂと乗り越し嵌合可能なようにしてある。グリップ部材７の後端部に形成した窓部７ａから軸筒５の外壁に形成した複数の突部６を突出させることにより、膨出部８近傍で、軸筒５とキャップ２の乗り越し嵌合が可能となり、経時によって、軸筒５の外壁に形成した突部６と、キャップ２の内壁に形成した凸部２ｂが擦り減る等、寸法変化が生じても、膨出部８とキャップの開口部２ａとの圧入嵌合をスムーズに行うことができる。
【００１４】
軸筒５にキャップ２を装着するには、軸筒５の外壁に形成した突部６と、キャップ２の内壁に形成した凸部２ｂが、乗り越し嵌合を開始し、その後、キャップ２の開口部２ａが、グリップ部材７の後端部に形成した膨出部８に当接する。さらに嵌合が進むと、キャップ２の開口部２ａと膨出部８との圧入嵌合が開始され、乗り越し嵌合を終了と同時に圧入嵌合も終了する。
【００１５】
キャップの開口部２ａと膨出部８との圧入嵌合を、弾性変形可能な弾性体で形成することにより、経時による寸法変化が少なく、軸筒５の外壁に形成した突部６と、キャップ２の内壁に形成した凸部２ｂの乗り越し嵌合の嵌合力が低下しても、圧入力が低下し難いため、容易に抜け落ちたり、横ぶれが発生しにくい。また、樹脂と樹脂の圧入嵌合に比べ、樹脂と弾性体のほうが気密性は高いので、キャップ内の気密性を確実に得ることができる。また、膨出部の形成方法は、実施の形態のように、膨出部に対向する軸筒に突状部を形成してもよいし、グリップ部材の膨出部に対応する部分の肉厚を多くしてあってもよい。
【００１６】
乗り越し嵌合前に圧入嵌合が開始されると、乗り越し嵌合時に、筆記先端部内へ空気が進入する等の悪影響を及ぼす恐れがあり、乗り越し嵌合後に圧入嵌合が開始されると、経時によって、軸筒の外壁に形成した突部と、キャップの内壁に形成した凸部が擦り減る等、寸法変化が生じた場合に、圧入嵌合がスムーズに行われない恐れがあるので、弾性体の膨出部とキャップの開口部は、軸筒の突部とキャップの凸部との乗り越し嵌合の開始後に圧入を開始し、乗り越し嵌合の終了と同時に圧入嵌合を終了する。
【００１７】
また、本実施の形態では、便宜上、筆記体としてボールペンレフィルを用いたが、ペン先部の材質や形状、使用する筆記具用インキ等に限定されることなく用いることができる。
【００１８】
【発明の効果】
本発明は、前述した構成なので、経時により寸法が変化しにくく、軸筒とキャップの嵌合力の低下、及びキャップ内の気密性が低下しにくいキャップ式筆記具を提供することができた。
【図面の簡単な説明】
【図１】第１の実施の形態のキャップ式筆記具を示す、一部省略した縦断面図である。
【図２】図１におけるキャップを示す、縦断面図である。
【図３】図１における軸筒を示す、一部省略した縦断面図である。
【符号の説明】
１キャップ式筆記具
２キャップ
２ａ開口部
２ｂ凸部
３クリップ
４弾性体
５軸筒
６突部
７グリップ部材
８膨出部
９インキ収容筒
１０チップホルダー
１１筆記先端部
Ｌキャップの開口部の内径
Ｍグリップ部材の膨出部の外径[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a cap-type writing instrument in which a cap is detachably attached to a shaft cylinder.
[0002]
[Prior art]
Conventionally, a protrusion formed on the outer wall of the shaft tube and a convex portion formed on the inner wall of the cap facing the protrusion are fitted over each other, so that the cap is detachably mounted on the shaft tube. Cap-type writing instruments are well known. Further, a cap-type writing instrument in which an elastic body is attached to the gripping portion of the shaft tube and a cap is attached so as to cover the elastic body is also well known, and is disclosed in Japanese Patent Application Laid-Open No. 2001-328392 “writing instrument”. ing.
[0003]
Such a cap-type writing instrument not only fits over the shaft cylinder and the cap, but also forms a step portion and a protrusion on the shaft tube on the rear end side of the elastic body attached to the grip portion of the shaft tube. And the outer diameter of the protrusion is larger than the inner diameter of the opening of the cap, so that the cap does not cause lateral shake with respect to the shaft tube, and the shaft tube and the cap are fitted over the cap. It also plays an auxiliary role. Moreover, if the step part and the protrusion part are continuously formed in a circumferential shape, the airtightness in the cap can be secured.
[0004]
[Patent Document 1]
"JP 2001-328392 A"
[0005]
[Problems to be solved by the invention]
However, since the conventional low-cost cap-type writing instrument is formed of a resin material for the shaft cylinder and / or the cap, in order to repeatedly attach and detach the cap, the protrusion formed on the outer wall of the shaft cylinder over time, A dimensional change is likely to occur, for example, the convex portion formed on the inner wall of the cap wears down, and as a result, the fitting force between the shaft tube and the cap may be reduced. Similarly, the inner wall of the cap and the protruding portion of the shaft cylinder change with time, and the pressure input is also reduced. Therefore, it is difficult to prevent the fitting force from being lowered, and the airtightness is also lowered.
[0006]
For this reason, since the shaft cylinder and the cap increase the pressure input, it is conceivable to set a lot of wrapping parts and ensure the airtightness inside the cap even if dimensional changes with time occur. When the cap is attached to the cap, the shaft tube and / or the cap may be cracked.
[0007]
In view of the above problems, the present invention provides a cap-type writing instrument that is less likely to change in size with time, is less likely to reduce the fitting force between the shaft tube and the cap, and less likely to reduce the airtightness in the cap.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, according to the present invention, a protrusion formed on the outer wall of the shaft cylinder in which a grip member made of an elastic body is attached to the grip portion, and a protrusion formed on the inner wall of the cap facing the protrusion. In a cap-type writing instrument in which a cap is detachably mounted so as to cover the grip portion of the shaft tube by fitting over the inner diameter, the inner diameter of the opening portion of the facing cap is arranged at the rear end portion of the grip member. A protrusion formed on the outer wall of the shaft cylinder protrudes from a window formed on the grip member, and a protrusion formed on the inner wall of the cap. However, after starting the over-fitting, the inner wall of the opening of the cap comes into contact with the bulging portion, and the press-fitting is finished at the same time as the over-fitting is finished, and the cap covers the grip member. Characterize .
[0009]
Further, the window portion is formed in the vicinity of a bulging portion formed at a rear end portion of the grip member .
[0010]
The grip member of the present invention is generally used as a grip member for writing instruments such as elastically deformable silicone rubber, natural rubber, butyl rubber, fluorine rubber, vinyl chloride resin, butadiene rubber, urethane rubber, polyethylene resin, other synthetic rubbers, thermoplastic elastomers, etc. What is necessary is just to select suitably from the elastic bodies known well.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings.
Although not shown, the cap-type writing instrument 1 shown in FIGS. 1 to 3 includes a tip holder 10 including a pen tip portion 11 formed of a ballpoint pen tip that rotatably holds a ball at the tip portion of the ink containing cylinder 9. The ballpoint pen refill mounted via the is accommodated in the shaft cylinder 5. The cap 2 is provided with an elastic body 4 that seals the tip of the pen tip 11, and a plurality of protrusions 6 formed on the outer wall of the shaft cylinder 5, and a circumferential protrusion 2 b formed on the inner wall of the cap 2. This is a cap-type writing instrument in which the cap 2 is detachably attached to the shaft tube 5 by overriding and fitting. A clip 3 is formed integrally with the cap 2.
[0012]
The grip portion 5a of the shaft tube 5 is formed to have a smaller diameter than the other shaft tube, and a grip member 7 made of an elastic body is attached to the small grip portion 5b. At this time, the bulging portion 8 having an outer diameter M larger than the inner diameter M of the opening 2 a of the cap 2 is formed at the rear end portion of the grip member 7 in a state where the grip member 7 is attached to the shaft cylinder 5. Further, a protruding portion 5b is formed at the rear end portion of the grip portion 5a. Further, the outer diameter of the grip member other than the bulging portion 8 is formed smaller than the inner diameter M of the opening 2a of the cap.
[0013]
Further, the plurality of protrusions 6 formed on the outer wall of the shaft cylinder 5 are projected from the window portion 7 a formed at the rear end portion of the grip member 7, thereby getting over the plurality of protrusions 2 b formed on the inner wall of the cap 2. It can be fitted. By projecting a plurality of protrusions 6 formed on the outer wall of the shaft tube 5 from the window 7a formed at the rear end portion of the grip member 7, the shaft tube 5 and the cap 2 are fitted over each other in the vicinity of the bulging portion 8. Even if a dimensional change occurs, such as the protrusion 6 formed on the outer wall of the shaft cylinder 5 and the projection 2b formed on the inner wall of the cap 2 wear down over time, the bulging portion 8 and the opening of the cap The press fitting with the part 2a can be performed smoothly.
[0014]
In order to attach the cap 2 to the shaft cylinder 5, the protrusion 6 formed on the outer wall of the shaft cylinder 5 and the convex part 2 b formed on the inner wall of the cap 2 start overpass fitting, and then the opening of the cap 2 is opened. The portion 2 a comes into contact with the bulging portion 8 formed at the rear end portion of the grip member 7. When the fitting further proceeds, the press-fitting between the opening 2a of the cap 2 and the bulging portion 8 is started, and the press-fitting is finished at the same time as the overpass fitting is finished.
[0015]
By forming the press-fitting between the opening 2a of the cap and the bulging portion 8 with an elastic body that can be elastically deformed, there is little dimensional change over time, and the projection 6 formed on the outer wall of the shaft tube 5, and the cap Even if the fitting force of the overhang fitting of the convex portion 2b formed on the inner wall of 2 is reduced, the pressure input is not easily lowered, so that it does not easily fall out or cause side shake. In addition, since the resin and the elastic body have higher airtightness than the resin-to-resin press-fitting, the airtightness in the cap can be reliably obtained. In addition, as for the method for forming the bulging portion, as in the embodiment, the protruding portion may be formed on the shaft cylinder facing the bulging portion, or the thickness of the portion corresponding to the bulging portion of the grip member You may have increased.
[0016]
If press-fitting is started before the over-fitting, there is a risk of adverse effects such as air entering the tip of the writing at the time of over-fitting. by a projection formed on the outer wall of the barrel, such as reduced rubbing convex portion formed on the inner wall of the cap, when the dimensional change occurs, the press-fitting might not be performed smoothly, the elastic member The bulge portion and the opening portion of the cap start press-fitting after the start of the over- fitting between the protruding portion of the shaft tube and the convex portion of the cap, and finish the press-fitting fitting at the same time as the end of the over-fitting.
[0017]
Further, in this embodiment, for the sake of convenience, a ballpoint pen refill is used as the writing body, but it can be used without being limited to the material and shape of the pen tip, the ink for the writing instrument to be used, and the like.
[0018]
【The invention's effect】
Since the present invention has the above-described configuration, it has been possible to provide a cap-type writing instrument in which the size hardly changes with time, the fitting force between the shaft tube and the cap does not decrease, and the airtightness in the cap does not easily decrease.
[Brief description of the drawings]
FIG. 1 is a partially omitted longitudinal sectional view showing a cap-type writing instrument according to a first embodiment.
2 is a longitudinal sectional view showing a cap in FIG. 1. FIG.
FIG. 3 is a partially omitted longitudinal sectional view showing the shaft cylinder in FIG. 1;
[Explanation of symbols]
1 Cap-type writing instrument 2 Cap 2a Opening
The outer diameter of the bulging portion of 2b the projections 3 the clip 4 elastic member 5 barrel 6 projections 7 grip member 8 protruding portion 9 ink reservoir tube 10 chip holder 11 writing tip L cap of the opening of the inner diameter M gripping member

Claims

A protrusion formed on the outer wall of the shaft cylinder formed by attaching a grip member made of an elastic body to the gripping part and a convex part formed on the inner wall of the cap facing the protrusion are fitted over the shaft, In a cap-type writing instrument in which a cap is detachably mounted so as to cover the gripping portion of the cylinder, a bulging portion having a diameter larger than the inner diameter of the opening portion of the opposing cap is formed at the rear end portion of the grip member. The protrusion formed on the outer wall of the shaft tube protrudes from the window formed on the grip member, and the protrusion and the protrusion formed on the inner wall of the cap start overpass fitting, A cap-type writing instrument , wherein an inner wall of an opening portion of a cap abuts on a bulging portion, and the press-fitting is completed at the same time as the over-fitting is completed, and the cap covers the grip member .

The said window part is formed in the vicinity of the bulging part formed in the rear-end part of the said grip member, The cap type writing instrument of Claim 1 characterized by the above-mentioned.