JP4548890B2

JP4548890B2 - Writing instrument cap

Info

Publication number: JP4548890B2
Application number: JP2000028643A
Authority: JP
Inventors: 正史安藤
Original assignee: Pilot Ink Co Ltd
Current assignee: Pilot Ink Co Ltd
Priority date: 2000-02-07
Filing date: 2000-02-07
Publication date: 2010-09-22
Anticipated expiration: 2020-02-07
Also published as: JP2001213088A

Description

【０００１】
【発明の属する技術分野】
本発明は、筆記具用キャップに関する。詳細には、筆跡消去用のイレーザと、ホワイトボード等の筆記板に吸着する平板状マグネットとを備えた筆記具用キャップに関する。尚、本発明において、「前」とはイレーザが装着保持される第一の筒部の開口側を指し、「後」とは筆記具本体が挿入される第二の筒部の開口側を指す。
【０００２】
【従来の技術】
例えば、実開昭５４−１６５２６号公報には、両端に、字消材が嵌挿される横断面方形状の有底孔と、筆記体が着脱自在に嵌着される横断面円形状の有底孔とを備えると共に、外面に磁性体が貼着された筆記具用キャップが開示されている。
【０００３】
【発明が解決しようとする課題】
前記従来の構造の筆記具用キャップは、平板状マグネットの面積が比較的小さく、吸着力が不足しがちである。そのため、筆記具本体が挿入保持されたキャップを、立設状態のホワイトボード等の筆記板の被吸着面に吸着保持したとしても、キャップ挿着状態の筆記具が衝撃等により前記被吸着面から容易に離脱・落下してしまう不具合があった。
【０００４】
また、前記従来の筆記具用キャップにおいて、マグネットの十分な吸着力を得るために単に平板状マグネットの面積を大きくしたのでは、キャップ全体（特にキャップの軸方向の全長）が筆記具本体に比較して大きくなり、不格好な外観を呈する。
【０００５】
また、従来のマグネット付きキャップは、キャップを挿着した筆記具がペン先上向き状態でホワイトボード等の立設状態の被吸着面に吸着されると、インキのドロップバック現象によって初期書き出し時の筆跡カスレを生じさせやすい。また、キャップを挿着した筆記具がペン先下向き状態で前記被吸着面に吸着されると、ペン先のインキの過剰供給によって、ペン先からインキが漏出するおそれがある。
【０００６】
本発明は、前記従来の課題を解決するものであって、キャップ全体を極端に大きくせずに、十分な吸着力を有するマグネットを備えたイレーザ付き筆記具用キャップを提供しようとするものである。また、立設状態の被吸着面に吸着保持したとしても、ペン先内のインキドロップバックによる筆跡のカスレや、インキの過剰供給によるペン先からのインキ漏出を防止する、マグネット及びイレーザ付きキャップを提供しようとするものである。
【０００７】
【課題を解決するための手段】
〔１〕本発明は、前端開口部に筆跡消去用のイレーザ５を装着保持し且つ外側面に平板状マグネット６を設けた横断面略方形状の第一の筒部２と、筆記具本体８が挿入保持可能な後端が開口され且つ前端が閉塞された横断面円形状の第二の筒部３とが一体に連結されてなる筆記具用キャップ１であって、前記第二の筒部３の前部に有底円筒状の筒状突出部３１を形成し、前記筒状突出部３１を前記第一の筒部２の内部に突出させ、前記筒状突出部３１の前端部が前記イレーザ５の後端面の中央部を当接支持し、前記第一の筒部２が横断面長方形状のイレーザ装着孔を有し、前記筒状突出部３１の外側の第一の筒部２の内面に、軸方向且つ長径方向に延びる板状リブ２２が一体に突設され、前記板状リブ２２の前端が前記イレーザ５の後端面の両縁部を当接支持してなること（請求項１）を要件とする。
【０００８】
（作用）
前記請求項１の構成により、マグネット６の十分な吸着力を得る目的でキャップ全体（特にキャップの軸方向の全長寸法）を極端に大きくすることがない。即ち、キャップ全体を極端に大きくすることなく平板状マグネット６の面積を大きくすることができるため、マグネット６の十分な吸着力を得ると同時にキャップの外観性も良好なものに保つことができる。
【０００９】
尚、前記第一の筒部２の「横断面略方形状」とは、第一の筒部２の横断面が、四角形状（例えば、正方形、長方形、平行四辺形、台形等）の他、少なくとも、一辺が平板状マグネット６を設けるための直線状となっていれば、他の部分は、曲線状であってもよい（例えば、半円形、半楕円形等）。
【００１０】
【００１１】
（作用）
前記請求項１の構成により、イレーザ５の中央部を安定支持でき、第一の筒部２内へのイレーザ５の埋没を防止できると共に、第一の筒部２の奥までイレーザ５を挿入保持する場合に比べ、イレーザ５の軸方向の長さを小さいものにでき、イレーザ５の材料費を低く抑えることができる。尚、前記第二の筒部３の前端部３１のイレーザ５を当接支持する箇所は、平面部であってもよいし、前記第二の筒部３の閉塞壁より前方に突出する縦リブや環状突起等であってもよい。
【００１２】
〔２〕前記請求項１の筆記具用キャップ１において、前記第一の筒部２と第二の筒部３との連結部４よりも前方の第二の筒部３（即ち筒状突出部３１）の内面に、筆記具本体８と気密嵌合する環状シール部３２を設け、前記環状シール部３２の位置する第二の筒部３（即ち筒状突出部３１）の外面と第一の筒部２の内面との間に環状間隙２１を設けること（請求項２）が好ましい。（図１、図５参照）
【００１３】
（作用）
前記請求項２の構成により、筆記具用キャップ１を、合成樹脂の射出成形の一体成形品により得る場合、前記環状間隙２１により、環状シール部３２の位置する第二の筒部３（筒状突出部３１）の周壁の肉厚を均一に保つことができるため、環状シール部３２におけるヒケの発生が回避され、筆記具本体８との気密嵌合不良を防止できる。
【００１４】
〔３〕前記請求項１の筆記具用キャップ１において、前記第一の筒部２と第二の筒部３との連結部４よりも後方、且つ、平板状マグネット６よりも後方の第二の筒部３の内面に、筆記具本体８と気密嵌合する環状シール部３２を設けること（請求項３）が好ましい。（図８、図１１参照）
【００１５】
（作用）
前記請求項３の構成により、筆記具用キャップ１を、合成樹脂の射出成形の一体成形品により得る場合、環状シール部３２の位置する第二の筒部３の周壁の肉厚を均一に保つことができるため、環状シール部３２におけるヒケの発生が回避され、筆記具本体８との気密嵌合不良を防止できる。
【００１６】
〔４〕前記請求項１、２又は３の筆記具用キャップ１において、筆記具本体のペン先側を前記第二の筒部３に挿入保持した際にペン先と接触状態となる多孔質含浸体７を、前記第二の筒部３の前端部３１内に配置すること（請求項４）が好ましい。
【００１７】
（作用）
キャップ１を挿着した筆記具が、ペン先上向き状態でホワイトボード等の立設状態の非吸着面に吸着されたとしても、多孔質含浸体７の毛細管力により、ペン先内のインキをドロップバックさせず、該インキドロップバック現象に伴う筆跡濃度の低下を防ぐことができる。また、キャップ１を挿着した筆記具が、ペン先下向き状態で前記非吸着面に吸着されたとしても、ペン先内の余剰インキを前記多孔質含浸体７に吸収させ、ペン先からのインキ漏出を防止できる。
【００１８】
【発明の実施の形態】
本発明の実施の形態について図面に従って説明する。
【００１９】
〔第１実施例〕
図１〜図７に第１実施例を示す。
【００２０】
キャップ１は、横断面が略方形状の第一の筒部２と、横断面が円形状の第二の筒部３とが、合成樹脂（例えばポリプロピレン樹脂等）の射出成形により一体に形成される。前記第一の筒部２と前記第二の筒部３とは、第一の筒部２後端部及び第二の筒部３の中間部外面に設けた連結部４にて一体に連結され、前記連結部４の前方の第一の筒部２内には、第二の筒部３の前部が有底円筒状に突出され、筒状突出部３１が形成されている。
【００２１】
前記第一の筒部２は、横断面が略長方形状のイレーザ装着孔を有し、該イレーザ装着孔の前端開口部より直方体形状に裁断されたフェルトからなるイレーザ５が圧入固着される。前記イレーザ５は、前端開口部より外部に突出される。
【００２２】
第一の筒部２の外側面には、平面状のマグネット取付部が凹設され、該マグネット取付部にシート状のマグネット６が貼着される。前記マグネット６は、第一の筒部２の外側面より外部に僅かに突出される。また、前記マグネット６の形状は、図６に示すように、長方形の後端に、略三角形、半円形、又は半楕円形を延設した形状を有する。
【００２３】
前記第二の筒部３の筒状突出部３１の内面には、筆記具本体８外面と気密嵌合する環状突起よりなる環状シール部３２が形成される。また、前記筒状突出部３１外面と第一の筒部２内面との間には、環状間隙２１が設けられ、それにより、環状シール部３２の位置する筒状突出部３１周壁の肉厚を均一なものにし、成形時のヒケの発生を抑え、筆記具本体８との気密嵌合不良を防止する。
【００２４】
前記第二の筒部３の前端部（即ち筒状突出部３１の前端部）はイレーザ５の後端面の中央部を当接支持している。また、前記筒状突出部３１の外側の第一の筒部２の内面には、軸方向且つ長径方向に延びる板状リブ２２が一体に突設される。前記板状リブ２２の前端は、前記イレーザ５の後端面の両縁部を当接支持している。即ち、前記板状リブ２２の前端と前記筒状突出部３１の前端とは、軸方向に略同じ位置に設定されている。
【００２５】
図１及び図３に示すように、前記連結部４と前記イレーザ５との間には、横断面略方形状の外側の第一の筒部２と、横断面円形状の内側の第二の筒部３（筒状突出部３１）とからなる２重筒構造を有する。
【００２６】
また、前記連結部４後方に延設される第二の筒部３の後部の内面には、筆記具本体８の外面と嵌合する複数（ここでは４個）の点状突起よりなる点状嵌合部３３が一体に形成される。
【００２７】
また、前記筒状突出部３１内の環状シール部３２より前方には、キャップを挿着した際にペン先８３と接触状態となる円柱状の多孔質含浸体７（例えば、フェルト、繊維の樹脂加工体、プラスチックポーラス体等）が圧入保持される。
【００２８】
〔第２実施例〕
図８〜図１１に第２実施例を示す。
【００２９】
第１実施例の変形例であって、第１実施例と大きく異なる点は、第二の筒部３の前端部（即ち筒状突出部３１）の外面と第一の筒部２の内面とが、軸方向且つ短径方向に延びる板状リブ２３によりにより連結されている点と、第二の筒部３の後部の内面に環状シール部３２を形成した点にある。
【００３０】
前記短径方向の板状リブ２３の前端は、長径方向の板状リブ２２の前端及び筒状突出部３１前端と軸方向に略同位置にあるため、短径方向の板状リブ２３、長径方向の板状リブ２２及び筒状突出部３１の三者の前端によって、イレーザ５の後端面が安定的に当接支持される。
【００３１】
また、前記環状シール部３２は、連結部４の後方且つ平板状マグネット６の後端よりも後方に位置するため、環状シール部３２の位置する第二の筒部３後部の周壁の肉厚を均一なものにし、成形時のヒケの発生を抑え、筆記具本体８との気密嵌合不良を防止する。
【００３２】
〔適用例〕
図１２に第１実施例及び第２実施例のキャップ１を適用した筆記具の例を示す。前記筆記具本体８は、軸筒８１内部に、インキが含浸された繊維収束体よりなるインキ吸蔵体８２を備え、軸筒８１前端部に、前記インキ吸蔵体８２と接続した繊維の樹脂加工体よりなるペン先８３を突出保持し、軸筒８１後端部に、前記インキ吸蔵体８２後端を当接支持し且つ軸筒８１後端開口部を密封する尾栓８４を嵌着した構成であり、前記筆記具本体８のペン先側外面には、本発明のキャップ１が着脱自在に挿着される。
【００３３】
〔その他〕
尚、本発明に用いるイレーザ５とは、筆跡消去手段であって、筆記具本体８がホワイトボードマーカー等の場合、前記実施例のフェルト以外にも筆跡を拭い取るものとして、繊維の樹脂加工体、プラスチックポーラス体、不織布等が挙げられる。また、筆記具本体８が鉛筆等の場合、消しゴム等が挙げられる。
【００３４】
尚、本発明に用いるマグネット６は、磁性を有するものであればよい。
【００３５】
【発明の効果】
請求項１の構成により、マグネットの十分な吸着力を得ると同時にキャップの外観性も良好なものに保つことができる。
【００３６】
前記請求項１の構成により、イレーザの中央部を安定支持でき、イレーザの没入を防止できると共に、第一の筒部の奥までイレーザを挿入保持する場合に比べ、イレーザの軸方向長さを小さいものにでき、イレーザの材料費を低く抑えることができる。
【００３７】
前記請求項２の構成により、環状シール部でのヒケの発生が回避され、筆記具本体との気密嵌合不良を防止できる。
【００３８】
前記請求項３の構成により、環状シール部でのヒケの発生が回避され、筆記具本体との気密嵌合不良を防止できる。
【００３９】
前記請求項４の構成により、キャップを挿着した筆記具を立設状態の被吸着面に吸着保持したとしても、ペン先内のインキドロップバックによる筆跡のカスレや、インキの過剰供給によるペン先からのインキ漏出を防止できる。
【図面の簡単な説明】
【図１】本発明の第１実施例を示す縦断面図である。
【図２】図１のＡ−Ａ線断面図である。
【図３】図１のＢ−Ｂ線断面図である。
【図４】図１のＣ−Ｃ線断面図である。
【図５】図１のＤ−Ｄ線断面図である。
【図６】本発明の第１実施例のマグネット側を示す正面図である。
【図７】図６の右側面図である。
【図８】本発明の第２実施例を示す縦断面図である。
【図９】図８のＥ−Ｅ線断面図である。
【図１０】図８のＦ−Ｆ線断面図である。
【図１１】図８のＧ−Ｇ線断面図である。
【図１２】本発明の筆記具用キャップを適用した筆記具の例を示す縦断面図である。
【符号の説明】
１キャップ
２第一の筒部
２１環状間隙
２２板状リブ（長径方向）
２３板状リブ（短径方向）
３第二の筒部
３１筒状突出部
３２環状シール部
３３点状嵌合部
４連結部
５イレーザ
６マグネット
７多孔質含浸体
８筆記具本体
８１軸筒
８２インキ吸蔵体
８３ペン先
８４尾栓[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a writing instrument cap. Specifically, the present invention relates to a writing instrument cap including an eraser for erasing handwriting and a flat magnet that is attracted to a writing board such as a white board. In the present invention, “front” refers to the opening side of the first tube portion on which the eraser is mounted and held, and “rear” refers to the opening side of the second tube portion into which the writing instrument body is inserted.
[0002]
[Prior art]
For example, Japanese Utility Model Laid-Open No. 54-16526 discloses a bottomed hole with a square cross-section into which an eraser is inserted at both ends, and a bottom with a circular cross-section into which a writing body is detachably fitted. A writing instrument cap having a hole and a magnetic material attached to the outer surface is disclosed.
[0003]
[Problems to be solved by the invention]
The writing instrument cap having the conventional structure has a relatively small area of the flat magnet, and tends to have insufficient attracting force. Therefore, even if the cap with the writing instrument main body inserted and held is sucked and held on the suction surface of a writing board such as a whiteboard standing upright, the writing tool with the cap inserted can be easily removed from the suction surface by an impact or the like. There was a problem of falling off and dropping.
[0004]
Further, in the conventional writing instrument cap, if the area of the flat magnet is simply increased in order to obtain a sufficient attracting force of the magnet, the entire cap (particularly, the total axial length of the cap) is larger than that of the writing instrument body. It grows and has an unsightly appearance.
[0005]
In addition, with a conventional cap with a magnet, when the writing instrument with the cap attached is attracted to the suction surface of the whiteboard or the like while the pen tip is facing upward, the ink mark drop-back phenomenon causes an ink drop during initial writing. It is easy to cause. In addition, when the writing instrument with the cap attached is attracted to the attracted surface in a state where the pen tip faces downward, ink may leak from the pen tip due to excessive supply of ink at the pen tip.
[0006]
The present invention is intended to solve the above-described conventional problems, and an object of the present invention is to provide a writing instrument cap with an eraser provided with a magnet having a sufficient attractive force without making the entire cap extremely large. A cap with magnet and eraser that prevents ink droplets from being lost due to ink dropback in the pen tip and ink leakage from the pen tip due to excessive supply of ink even if it is held by suction on the surface to be sucked up. It is something to be offered.
[0007]
[Means for Solving the Problems]
[1] In the present invention, the first cylindrical portion 2 having a substantially rectangular cross section in which the eraser 5 for erasing the handwriting is mounted and held in the front end opening and the flat magnet 6 is provided on the outer surface, and the writing instrument body 8 include A writing instrument cap 1 formed by integrally connecting a second cylindrical portion 3 having a circular cross-section with a rear end that can be inserted and held open and a closed front end , the bottomed cylindrical tubular projection 31 formed on the front, the cylindrical projecting portion 31 was issued collision within said first cylindrical portion 2, a front end portion of the tubular projecting portion 31 is the eraser 5, the central portion of the rear end face is abutted and supported, the first cylindrical portion 2 has an eraser mounting hole having a rectangular cross section, and the inner surface of the first cylindrical portion 2 outside the cylindrical protruding portion 31. Further, a plate-like rib 22 extending in the axial direction and the long-diameter direction is integrally projected, and the front end of the plate-like rib 22 is the rear end surface of the eraser 5. It is an edge and contacts and supports the (claim 1) and requirements.
[0008]
(Function)
According to the configuration of the first aspect, the entire cap (particularly, the overall length in the axial direction of the cap) is not extremely increased for the purpose of obtaining a sufficient attractive force of the magnet 6. That is, since the area of the flat magnet 6 can be increased without making the entire cap extremely large, it is possible to obtain a sufficient attractive force of the magnet 6 and at the same time maintain the appearance of the cap.
[0009]
In addition, the “cross-sectional substantially square shape” of the first cylindrical portion 2 means that the first cylindrical portion 2 has a rectangular cross-section (for example, a square, a rectangle, a parallelogram, a trapezoid, etc.) As long as at least one side is a straight line for providing the flat magnet 6, the other part may be a curved line (for example, a semicircle, a semi-ellipse, etc.).
[0010]
[0011]
(Function)
The arrangement of claim 1, can stably support a central portion of the eraser 5, it is possible to prevent burial eraser 5 to the first tubular portion 2, inserting holding the eraser 5 all the way into the first cylindrical portion 2 Compared to the case, the length of the eraser 5 in the axial direction can be reduced, and the material cost of the eraser 5 can be kept low. The portion of the front end portion 31 of the second cylindrical portion 3 that contacts and supports the eraser 5 may be a flat portion, or a vertical rib that protrudes forward from the closing wall of the second cylindrical portion 3. Or an annular protrusion or the like.
[0012]
[ 2 ] In the writing instrument cap 1 according to claim 1, the second cylindrical portion 3 (that is, the cylindrical protruding portion 31) in front of the connecting portion 4 between the first cylindrical portion 2 and the second cylindrical portion 3 is provided. ) Is provided with an annular seal portion 32 that is airtightly fitted to the writing instrument main body 8, and the outer surface of the second cylindrical portion 3 (that is, the cylindrical protruding portion 31) where the annular seal portion 32 is located and the first cylindrical portion. It is preferable to provide an annular gap 21 between the two inner surfaces (Claim 2 ). (See Figs. 1 and 5)
[0013]
(Function)
The arrangement of claim 2, when the writing instrument cap 1, obtained by integrally molded product of the injection molding of synthetic resin, by the annular gap 21, the second cylindrical portion 3 to the position of the annular seal portion 32 (tubular projection Since the thickness of the peripheral wall of the portion 31) can be kept uniform, the occurrence of sink marks in the annular seal portion 32 can be avoided, and the poor airtight fitting with the writing instrument body 8 can be prevented.
[0014]
[ 3 ] In the writing instrument cap 1 according to the first aspect, a second rear side of the connecting portion 4 between the first cylindrical portion 2 and the second cylindrical portion 3 and a rear side of the flat magnet 6 is provided. It is preferable to provide an annular seal portion 32 that is airtightly fitted to the writing instrument body 8 on the inner surface of the cylindrical portion 3 (Claim 3 ). (See FIGS. 8 and 11)
[0015]
(Function)
According to the configuration of the third aspect , when the writing instrument cap 1 is obtained by an integrally molded product of synthetic resin injection molding, the thickness of the peripheral wall of the second cylindrical portion 3 where the annular seal portion 32 is located is kept uniform. Therefore, the occurrence of sink marks in the annular seal portion 32 can be avoided, and poor airtight fitting with the writing instrument body 8 can be prevented.
[0016]
[ 4 ] The porous impregnated body 7 that comes into contact with the pen tip when the pen tip side of the writing tool body is inserted and held in the second cylindrical portion 3 in the writing instrument cap 1 according to claim 1, 2, or 3. Is preferably disposed in the front end portion 31 of the second cylindrical portion 3 (Claim 4 ).
[0017]
(Function)
Even if the writing instrument with the cap 1 inserted is adsorbed to the non-adsorbing surface of the whiteboard or the like when the pen tip is upward, the ink in the nib is dropped back by the capillary force of the porous impregnated body 7 Without this, it is possible to prevent a reduction in handwriting density due to the ink dropback phenomenon. Further, even if the writing instrument with the cap 1 inserted is adsorbed to the non-adsorbing surface in a state where the pen tip is downward, excess ink in the pen tip is absorbed by the porous impregnated body 7 and ink leakage from the pen tip is caused. Can be prevented.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings.
[0019]
[First embodiment]
1 to 7 show a first embodiment.
[0020]
In the cap 1, a first tube portion 2 having a substantially rectangular cross section and a second tube portion 3 having a circular cross section are integrally formed by injection molding of a synthetic resin (eg, polypropylene resin). The The first tube portion 2 and the second tube portion 3 are integrally connected by a connecting portion 4 provided on a rear end portion of the first tube portion 2 and an intermediate portion outer surface of the second tube portion 3. In the first cylinder part 2 in front of the connecting part 4, the front part of the second cylinder part 3 protrudes in a bottomed cylindrical shape, and a cylindrical protrusion 31 is formed.
[0021]
The first cylindrical portion 2 has an eraser mounting hole having a substantially rectangular cross section, and an eraser 5 made of felt cut into a rectangular parallelepiped shape from a front end opening of the eraser mounting hole is press-fitted and fixed. The eraser 5 is projected outside from the front end opening.
[0022]
A planar magnet attachment portion is recessed in the outer surface of the first tube portion 2, and a sheet-like magnet 6 is attached to the magnet attachment portion. The magnet 6 slightly protrudes from the outer surface of the first cylindrical portion 2 to the outside. As shown in FIG. 6, the magnet 6 has a shape in which a substantially triangular, semicircular, or semielliptical shape is extended at the rear end of the rectangle.
[0023]
On the inner surface of the cylindrical protruding portion 31 of the second cylindrical portion 3, an annular seal portion 32 made of an annular protrusion that is airtightly fitted to the outer surface of the writing instrument body 8 is formed. Further, an annular gap 21 is provided between the outer surface of the cylindrical protruding portion 31 and the inner surface of the first cylindrical portion 2, thereby increasing the thickness of the peripheral wall of the cylindrical protruding portion 31 where the annular seal portion 32 is located. Uniform, suppresses the occurrence of sink marks during molding, and prevents poor airtight fitting with the writing instrument body 8.
[0024]
The front end portion of the second cylindrical portion 3 (that is, the front end portion of the cylindrical projecting portion 31) abuts and supports the central portion of the rear end surface of the eraser 5. A plate-like rib 22 extending in the axial direction and the long-diameter direction is integrally projected on the inner surface of the first cylindrical portion 2 outside the cylindrical protruding portion 31. The front end of the plate-like rib 22 abuts and supports both edges of the rear end surface of the eraser 5. That is, the front end of the plate-like rib 22 and the front end of the cylindrical protrusion 31 are set at substantially the same position in the axial direction.
[0025]
As shown in FIGS. 1 and 3, between the connecting portion 4 and the eraser 5, a first cylindrical portion 2 having a substantially rectangular cross section and a second inner portion having a circular cross section are provided. It has a double cylinder structure consisting of the cylinder part 3 (cylindrical protrusion part 31).
[0026]
In addition, a point-like fitting made up of a plurality of (four in this case) point-like protrusions fitted to the outer surface of the writing instrument body 8 is formed on the inner surface of the rear portion of the second cylindrical portion 3 extending behind the connecting portion 4. The joint portion 33 is formed integrally.
[0027]
A cylindrical porous impregnated body 7 (for example, felt or fiber resin) that comes into contact with the pen tip 83 when a cap is inserted is provided in front of the annular seal portion 32 in the cylindrical protruding portion 31. A processed body, a plastic porous body, etc.) are press-fitted and held.
[0028]
[Second Embodiment]
8 to 11 show a second embodiment.
[0029]
A modification of the first embodiment, which differs greatly from the first embodiment, is that the outer surface of the front end portion of the second cylindrical portion 3 (that is, the cylindrical protruding portion 31) and the inner surface of the first cylindrical portion 2 are Are connected by a plate-like rib 23 extending in the axial direction and the minor axis direction, and an annular seal portion 32 is formed on the inner surface of the rear portion of the second cylindrical portion 3.
[0030]
Since the front end of the plate rib 23 in the short diameter direction is substantially in the same axial position as the front end of the plate rib 22 in the long diameter direction and the front end of the cylindrical protrusion 31, the plate rib 23 in the short diameter direction and the long diameter The rear end face of the eraser 5 is stably abutted and supported by the three front ends of the plate-like rib 22 and the cylindrical protrusion 31 in the direction.
[0031]
Further, since the annular seal portion 32 is located behind the connecting portion 4 and behind the rear end of the flat magnet 6, the thickness of the peripheral wall of the rear portion of the second cylindrical portion 3 where the annular seal portion 32 is located is reduced. Uniform, suppresses the occurrence of sink marks during molding, and prevents poor airtight fitting with the writing instrument body 8.
[0032]
[Application example]
FIG. 12 shows an example of a writing instrument to which the cap 1 of the first embodiment and the second embodiment is applied. The writing instrument main body 8 includes an ink occlusion body 82 made of a fiber converging body impregnated with ink inside the shaft cylinder 81, and a fiber resin processed body connected to the ink occlusion body 82 at the front end portion of the shaft cylinder 81. The pen tip 83 is protruded and held, and a tail plug 84 that abuts and supports the rear end of the ink storage body 82 and seals the rear end opening of the shaft cylinder 81 is fitted to the rear end of the shaft cylinder 81. The cap 1 of the present invention is detachably inserted on the pen tip side outer surface of the writing instrument body 8.
[0033]
[Others]
The eraser 5 used in the present invention is a handwriting erasing means, and when the writing tool body 8 is a whiteboard marker or the like, it is assumed that the handwriting is wiped in addition to the felt of the above embodiment, a fiber resin processed body, A plastic porous body, a nonwoven fabric, etc. are mentioned. Moreover, when the writing instrument main body 8 is a pencil etc., an eraser etc. are mentioned.
[0034]
In addition, the magnet 6 used for this invention should just have magnetism.
[0035]
【The invention's effect】
According to the configuration of the first aspect, a sufficient attractive force of the magnet can be obtained and at the same time, the appearance of the cap can be kept good.
[0036]
The arrangement of claim 1, eraser central portion can stably support the also prevent immersive the eraser, as compared to when inserting holding the eraser all the way into the first cylindrical portion, a small axial length of the eraser The material cost of the eraser can be kept low.
[0037]
With the configuration of the second aspect , the occurrence of sink marks in the annular seal portion is avoided, and poor airtight fitting with the writing instrument body can be prevented.
[0038]
With the configuration of the third aspect , the occurrence of sink marks at the annular seal portion is avoided, and poor airtight fitting with the writing instrument body can be prevented.
[0039]
According to the configuration of claim 4 , even if the writing tool with the cap inserted is sucked and held on the suction surface in the standing state, the writing mark is not smeared by the ink dropback in the pen tip, or the pen tip is caused by excessive supply of ink. Ink leakage can be prevented.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing a first embodiment of the present invention.
FIG. 2 is a cross-sectional view taken along line AA in FIG.
FIG. 3 is a cross-sectional view taken along line BB in FIG.
4 is a cross-sectional view taken along the line CC in FIG. 1. FIG.
5 is a cross-sectional view taken along line DD of FIG.
FIG. 6 is a front view showing the magnet side of the first embodiment of the present invention.
7 is a right side view of FIG. 6. FIG.
FIG. 8 is a longitudinal sectional view showing a second embodiment of the present invention.
9 is a cross-sectional view taken along the line EE of FIG.
10 is a cross-sectional view taken along line FF in FIG.
11 is a cross-sectional view taken along the line GG of FIG.
FIG. 12 is a longitudinal sectional view showing an example of a writing instrument to which the writing instrument cap of the present invention is applied.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Cap 2 1st cylinder part 21 Annular gap | interval 22 Plate-like rib (major-diameter direction)
23 Plate-shaped rib (minor axis direction)
3 Second cylinder part 31 Cylindrical protrusion part 32 Annular seal part 33 Dot fitting part 4 Connection part 5 Erase 6 Magnet 7 Porous impregnated body 8 Writing instrument body 81 Shaft cylinder 82 Ink occlusion body 83 Pen tip 84 Tail plug

Claims

A first cylindrical portion having a substantially rectangular cross-section with an eraser for erasing handwriting at the front end opening and a flat magnet provided on the outer surface, and a rear end opened to allow the writing instrument body to be inserted and held and the front end A cap for a writing instrument in which a second cylindrical portion having a circular cross-section with a closed cross-section is integrally connected, and a cylindrical projection with a bottomed cylindrical shape is formed at the front of the second cylindrical portion and causes out collision of the tubular projecting portion into the interior of the first cylindrical portion, a central portion of the rear end surface of the front end portion of the tubular projecting portion is the erasure abut support, said first cylindrical portion Has a rectangular cross-sectional eraser mounting hole, and a plate-like rib extending in the axial direction and the long-diameter direction is integrally projected on the inner surface of the first cylindrical portion outside the cylindrical protruding portion. A writing instrument cap, wherein the front end of the rib is in contact with and supports both edge portions of the rear end face of the eraser .

Provided on the inner surface of the second cylindrical portion in front of the connecting portion between the first cylindrical portion and the second cylindrical portion is an annular seal portion that is airtightly fitted to the writing instrument body, and the annular seal portion is positioned at the first position. The writing instrument cap according to claim 1, wherein an annular gap is provided between the outer surface of the second cylindrical portion and the inner surface of the first cylindrical portion .

An annular seal portion is provided on the inner surface of the second tube portion behind the connecting portion between the first tube portion and the second tube portion and behind the flat magnet so as to be airtightly fitted to the writing instrument body. The writing instrument cap according to claim 1 .

The porous impregnated body that comes into contact with the pen tip when the pen tip side of the writing instrument body is inserted and held in the second tube portion is disposed in the front end portion of the second tube portion. The writing instrument cap according to any one of the preceding claims.