JP2024065887A - Thermochromic writing implements - Google Patents

Thermochromic writing implements Download PDF

Info

Publication number
JP2024065887A
JP2024065887A JP2022174964A JP2022174964A JP2024065887A JP 2024065887 A JP2024065887 A JP 2024065887A JP 2022174964 A JP2022174964 A JP 2022174964A JP 2022174964 A JP2022174964 A JP 2022174964A JP 2024065887 A JP2024065887 A JP 2024065887A
Authority
JP
Japan
Prior art keywords
cylinder
fitting portion
writing instrument
wall portion
outer cylinder
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP2022174964A
Other languages
Japanese (ja)
Inventor
幹也 井戸
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Pilot Corp
Original Assignee
Pilot Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Pilot Corp filed Critical Pilot Corp
Priority to JP2022174964A priority Critical patent/JP2024065887A/en
Publication of JP2024065887A publication Critical patent/JP2024065887A/en
Pending legal-status Critical Current

Links

Images

Landscapes

  • Pens And Brushes (AREA)

Abstract

【課題】内側嵌合部に傷が付くことを防ぎ、内筒体と外筒体との嵌合性能を確実に確保することができることに加え、内筒体の外筒体内への挿入性が向上する熱変色性筆記具を提供する。【解決手段】熱変色性インキが内蔵され且つ該インキが吐出可能なペン先21を備える筆記具本体2又は筆記具本体2のペン先21に取り付け可能なキャップ本体7を備える。筆記具本体2又はキャップ本体7が、外筒体4と、該外筒体4の内面に嵌着される内筒体5とを備える。内筒体5の外面には外側嵌合部51が形成される。外筒体4の内面に外側嵌合部51と嵌合する内側嵌合部43が形成される。内筒体5の外面には後方に面する当接壁部54が形成される。外筒体4の内面には当接壁部54と前後方向に当接する規制壁部44が一体に形成される。規制壁部44は内側嵌合部43より前方に設けられている【選択図】 図1[Problem] To provide a thermochromic writing implement that prevents damage to an inner fitting portion, reliably ensures the fitting performance between an inner cylinder and an outer cylinder, and improves insertability of the inner cylinder into an outer cylinder. [Solution] A writing implement body 2 having a pen tip 21 that contains thermochromic ink and can eject the ink, or a cap body 7 that can be attached to the pen tip 21 of the writing implement body 2. The writing implement body 2 or the cap body 7 includes an outer cylinder 4 and an inner cylinder 5 that is fitted to the inner surface of the outer cylinder 4. An outer fitting portion 51 is formed on the outer surface of the inner cylinder 5. An inner fitting portion 43 that fits with the outer fitting portion 51 is formed on the inner surface of the outer cylinder 4. An abutment wall portion 54 facing rearward is formed on the outer surface of the inner cylinder 5. A regulating wall portion 44 that abuts against the abutment wall portion 54 in the front-rear direction is integrally formed on the inner surface of the outer cylinder 4. The restricting wall portion 44 is provided forward of the inner fitting portion 43 [selected figure] FIG. 1

Description

本発明は、熱変色性筆記具に関する。詳細には、摩擦体を備えた熱変色性筆記具の筆記具本体の後端部又はキャップ本体を外筒体により構成し、前記外筒体の内面に内筒体を固着してなる熱変色性筆記具に関する。 The present invention relates to a thermochromic writing instrument. In particular, the present invention relates to a thermochromic writing instrument having a friction body, the rear end of the writing instrument body or the cap body of the thermochromic writing instrument being constituted by an outer cylinder, and an inner cylinder being fixed to the inner surface of the outer cylinder.

従来、特許文献1には、筆記具本体を構成する筒体の内面に栓体の外面と気密嵌合する内側シール部を形成し、前記内側シール部後方の筒体の内面に、栓体の後面と前後方向に当接し且つ栓体の後方への移動を阻止する規制壁部を一体に形成した筆記具が開示されている。 Patent Document 1 discloses a writing instrument in which an inner seal is formed on the inner surface of a cylinder constituting the main body of the writing instrument, which fits airtight with the outer surface of a stopper, and a restricting wall is integrally formed on the inner surface of the cylinder behind the inner seal, which abuts against the rear surface of the stopper in the front-to-rear direction and prevents the stopper from moving backward.

また、特許文献2には、キャップ本体の内面に内側嵌合部を形成し、前記内側嵌合部より後方のキャップ本体内面に、前記内側嵌合部の内径より小さい内径を有する規制壁部を一体に形成し、前記内側嵌合部と内キャップ外面の外側嵌合部とを嵌合させるとともに、前記規制壁部に内キャップの後面を当接させた筆記具用キャップが開示されている。 Patent document 2 also discloses a writing instrument cap in which an inner fitting portion is formed on the inner surface of the cap body, and a regulating wall portion having an inner diameter smaller than the inner diameter of the inner fitting portion is integrally formed on the inner surface of the cap body rearward of the inner fitting portion, and the inner fitting portion is fitted into an outer fitting portion on the outer surface of the inner cap, and the rear surface of the inner cap is abutted against the regulating wall portion.

特願2009-106070号公報Patent Application No. 2009-106070 特願2008-143367号公報Patent Application No. 2008-143367

特許文献1及び特許文献2の筆記具において、規制壁部が内側嵌合部より後方に設けられていることにより、外筒体(筒体、キャップ本体)内へ内筒体(栓体、内キャップ)を挿入する際に内筒体の後部(規制壁部と当接する箇所)が引っかかって内側嵌合部に傷が付き、適切な嵌合性能が得られないおそれがあった。例えば、特許文献1においては、筒体内に栓体を挿入する際、栓体が傾いて挿入されると、栓体の後端が内側シール部に引っかかるおそれがあった。特許文献2においては、キャップ本体内に内キャップを挿入する際、内キャップが傾いて挿入されると、内キャップの外側嵌合部の後端が内側嵌合部に引っかかるおそれがあった。 In the writing implements of Patent Documents 1 and 2, the regulating wall is provided behind the inner fitting portion, so that when the inner barrel (stopper, inner cap) is inserted into the outer barrel (barrel, cap body), the rear portion of the inner barrel (the portion that abuts against the regulating wall portion) may get caught and scratch the inner fitting portion, resulting in a risk of not being able to achieve proper fitting performance. For example, in Patent Document 1, if the stopper is inserted at an angle when inserted into the barrel, the rear end of the stopper may get caught on the inner seal portion. In Patent Document 2, if the inner cap is inserted at an angle when inserted into the cap body, the rear end of the outer fitting portion of the inner cap may get caught on the inner fitting portion.

特に、特許文献1においては、筒体と栓体とが気密嵌合しているため、内側シール部に傷が付くと適切な気密性能が得られないおそれがあった。 In particular, in Patent Document 1, the cylinder and the plug are airtightly fitted together, so if the inner seal is damaged, there is a risk that appropriate airtightness will not be achieved.

さらに、規制壁部が内側嵌合部より後方に設けられていることにより、内筒体の内側嵌合部より後方の外径を規制壁部の内径より大きくする必要があった。内筒体の後部の外径が大きいことにより、内筒体の外筒体内への挿入性が低下するおそれがあった。 Furthermore, because the restricting wall portion is provided rearward of the inner fitting portion, it was necessary to make the outer diameter of the inner cylinder body rearward of the inner fitting portion larger than the inner diameter of the restricting wall portion. As the outer diameter of the rear portion of the inner cylinder body is larger, there was a risk that the insertability of the inner cylinder body into the outer cylinder body would be reduced.

本発明は、前記従来の問題点を解決するものであって、内側嵌合部に傷が付くことを防ぎ、内筒体と外筒体との嵌合性能を確実に確保することができることに加え、内筒体の外筒体内への挿入性が向上する熱変色性筆記具を提供しようとするものである。特に、外筒体が気密性能を必要とする場合、内筒体外面と外筒体内面との気密を確実に確保することができる熱変色性筆記具を提供する。本発明では、筆記具本体において「前」とはペン先側を指し、「後」とはその反対側を指す。キャップ本体において「前」とはキャップの開口側(即ちペン先挿入側)を指し、「後」とはその反対側を指す。 The present invention aims to solve the above-mentioned problems of the conventional art by providing a thermochromic writing instrument that prevents scratches on the inner fitting portion, reliably ensures the fitting performance of the inner and outer barrels, and improves the insertability of the inner barrel into the outer barrel. In particular, when the outer barrel requires airtight performance, a thermochromic writing instrument is provided that can reliably ensure airtightness between the outer surface of the inner barrel and the inner surface of the outer barrel. In this invention, in the writing instrument body, "front" refers to the nib side, and "rear" refers to the opposite side. In the cap body, "front" refers to the opening side of the cap (i.e., the nib insertion side), and "rear" refers to the opposite side.

本願の第1の発明は、熱変色性インキが内蔵され且つ該インキが吐出可能なペン先を備える筆記具本体又は前記筆記具本体の前記ペン先に取り付け可能なキャップ本体を備え、前記筆記具本体又は前記キャップ本体に取り付けられ、前記熱変色性インキの筆跡を摩擦する摩擦体を備えた熱変色性筆記具であって、
前記筆記具本体又は前記キャップ本体が、外筒体と、該外筒体の内面に嵌着される内筒体とを備え、
前記外筒体の後端には前記摩擦体が装着され、
前記内筒体の外面には外側嵌合部が形成され、前記外筒体の内面に前記外側嵌合部と嵌合する内側嵌合部が形成され、
前記内筒体の外面には後方に面する当接壁部が形成され、前記外筒体の内面には前記当接壁部と前後方向に当接し且つ前記内筒体の後方への移動を阻止する規制壁部が一体に形成され、前記規制壁部は前記内側嵌合部より前方に設けられていることを特徴とする。
A first aspect of the present invention is a thermochromic writing instrument comprising a writing instrument body having a thermochromic ink built therein and a pen tip capable of discharging the ink, or a cap body that can be attached to the pen tip of the writing instrument body, and a friction body that is attached to the writing instrument body or the cap body and rubs the handwriting of the thermochromic ink,
The writing instrument body or the cap body includes an outer cylinder body and an inner cylinder body fitted to the inner surface of the outer cylinder body,
The friction body is attached to the rear end of the outer cylinder,
An outer fitting portion is formed on the outer surface of the inner cylinder, and an inner fitting portion that fits with the outer fitting portion is formed on the inner surface of the outer cylinder,
The present invention is characterized in that a rearward-facing abutment wall portion is formed on the outer surface of the inner cylinder, and a control wall portion is integrally formed on the inner surface of the outer cylinder that abuts against the abutment wall portion in the front-to-rear direction and prevents the inner cylinder from moving rearward, and the control wall portion is located forward of the inner fitting portion.

前記第1の発明の筆記具は、前記構成により、内筒体を外筒体内へ挿入する際に内筒体が外筒体の内面に引っかかって内側嵌合部に傷が付くことを防ぐことができる。また、内側嵌合部より前方の規制壁部によって内筒体の移動を規制するため、内筒体の外側嵌合部より後方の外径を任意に設定することができ、内筒体の外筒体内への挿入性が向上する。 The writing instrument of the first invention, with the above configuration, can prevent the inner cylinder from getting caught on the inner surface of the outer cylinder and damaging the inner fitting portion when the inner cylinder is inserted into the outer cylinder. In addition, since the movement of the inner cylinder is restricted by the restricting wall portion in front of the inner fitting portion, the outer diameter of the inner cylinder behind the outer fitting portion can be set as desired, improving the insertability of the inner cylinder into the outer cylinder.

本願の第2の発明は、熱変色性インキが内蔵され且つ該インキが吐出可能なペン先を備える筆記具本体又は前記筆記具本体の前記ペン先に取り付け可能なキャップ本体を備え、前記筆記具本体又は前記キャップ本体に取り付けられ、前記熱変色性インキの筆跡を摩擦する摩擦体を備えた熱変色性筆記具であって、
前記筆記具本体又は前記キャップ本体が、外筒体と、該外筒体の内面に嵌着される内筒体とを備え、
前記外筒体が、前後方向に貫通する内孔と、該内孔に連通する前端開口部及び後端開口部とを備え、
前記外筒体の前記後端開口部には前記摩擦体が装着され、
前記内筒体の外面には外側嵌合部が形成され、前記外筒体の内面に前記外側嵌合部と気密嵌合する内側嵌合部が形成され、
前記内筒体の外面には後方に面する当接壁部が形成され、前記外筒体の内面には前記当接壁部と前後方向に当接し且つ前記内筒体の後方への移動を阻止する規制壁部が一体に形成され、前記規制壁部は前記内側嵌合部より前方に設けられていることを特徴とする。
A second aspect of the present invention is a thermochromic writing instrument comprising a writing instrument body having a thermochromic ink built therein and a pen tip capable of discharging the ink, or a cap body that can be attached to the pen tip of the writing instrument body, and a friction body that is attached to the writing instrument body or the cap body and rubs the handwriting of the thermochromic ink,
The writing instrument body or the cap body includes an outer cylinder body and an inner cylinder body fitted to the inner surface of the outer cylinder body,
the outer cylinder body has an inner hole penetrating in the front-rear direction, and a front end opening and a rear end opening communicating with the inner hole,
The friction body is attached to the rear end opening of the outer cylinder body,
An outer fitting portion is formed on an outer surface of the inner cylinder, and an inner fitting portion that fits airtightly with the outer fitting portion is formed on an inner surface of the outer cylinder,
The present invention is characterized in that a rearward-facing abutment wall portion is formed on the outer surface of the inner cylinder, and a control wall portion is integrally formed on the inner surface of the outer cylinder that abuts against the abutment wall portion in the front-to-rear direction and prevents the inner cylinder from moving rearward, and the control wall portion is located forward of the inner fitting portion.

前記第2の発明の熱変色性筆記具は、前記構成により、内筒体を外筒体内へ挿入する際に内筒体が外筒体の内面に引っかかって内側嵌合部に傷が付くことを防ぎ、内筒体外面と外筒体内面との気密を確実に確保することができる。また、内側嵌合部より前方の規制壁部によって内筒体の移動を規制するため、内筒体の後端の外径を任意に設定することができ、内筒体の外筒体内への挿入性が向上する。 The thermochromic writing instrument of the second invention, with the above-mentioned configuration, can prevent the inner cylinder from getting caught on the inner surface of the outer cylinder when inserting the inner cylinder into the outer cylinder, causing damage to the inner fitting portion, and can reliably ensure airtightness between the outer surface of the inner cylinder and the inner surface of the outer cylinder. In addition, since the movement of the inner cylinder is restricted by the restricting wall portion in front of the inner fitting portion, the outer diameter of the rear end of the inner cylinder can be set as desired, improving the insertability of the inner cylinder into the outer cylinder.

本願の第3の発明は、熱変色性インキが内蔵され且つ該インキが吐出可能なペン先を備える筆記具本体と、前記筆記具本体の前記ペン先に取り付け可能なキャップ本体と、前記キャップ本体に取り付けられ、前記熱変色性インキの筆跡を摩擦する摩擦体と、を備えた熱変色性筆記具であって、
前記キャップ本体が、外筒体と、該外筒体の内面に嵌着される内筒体とを備え、
前記外筒体の後端には前記摩擦体が装着され、
前記内筒体の外面には外側嵌合部が形成され、前記外筒体の内面に前記外側嵌合部と嵌合する内側嵌合部が形成され、
前記内筒体の外面には後方に面する当接壁部が形成され、前記内側嵌合部より前方の前記外筒体の内面には前記当接壁部と前後方向に当接し且つ前記内筒体の後方への移動を阻止する規制壁部が一体に形成され、
前記内筒体の内面の前端には前記筆記具本体と気密嵌合する環状シール部が設けられ、
前記外側嵌合部は前記当接壁部より後方に設けられ、前記当接壁部は前記環状シール部より後方に設けられることを特徴とする。
A third aspect of the present invention is a thermochromic writing instrument comprising: a writing instrument body having a thermochromic ink built therein and a pen tip capable of discharging the ink; a cap body that can be attached to the pen tip of the writing instrument body; and a friction body that is attached to the cap body and rubs the writing of the thermochromic ink,
The cap body includes an outer cylinder and an inner cylinder fitted to the inner surface of the outer cylinder,
The friction body is attached to the rear end of the outer cylinder,
An outer fitting portion is formed on the outer surface of the inner cylinder, and an inner fitting portion that fits with the outer fitting portion is formed on the inner surface of the outer cylinder,
a rearward-facing abutment wall portion is formed on an outer surface of the inner cylinder body, and a restricting wall portion is integrally formed on an inner surface of the outer cylinder body forward of the inner fitting portion, the restricting wall portion abutting against the abutment wall portion in the front-rear direction and preventing the inner cylinder body from moving rearward;
An annular seal portion is provided at the front end of the inner surface of the inner cylinder and is airtightly fitted with the writing instrument body,
The outer fitting portion is provided rearward of the contact wall portion, and the contact wall portion is provided rearward of the annular seal portion.

本願の第3の発明の熱変色性筆記具は、前記構成により、キャップ本体のキャップとしての気密性能を維持しつつ、内筒体を外筒体内へ挿入する際に内筒体が外筒体の内面に引っかかって内側嵌合部に傷が付くことを防ぐことができる。 The thermochromic writing instrument of the third invention of the present application, with the above-mentioned configuration, can maintain the airtight performance of the cap body as a cap, while preventing the inner cylinder from getting caught on the inner surface of the outer cylinder when inserting the inner cylinder into the outer cylinder, causing damage to the inner fitting portion.

本願の第4の発明は、前記第1乃至第3の何れかの発明において、前記外側嵌合部より前方の前記内筒体の外面には径方向外方に突出する鍔部が設けられており、前記鍔部の後端に前記当接壁部が設けられていることが好ましい。 The fourth invention of the present application is any one of the first to third inventions, in which a flange portion protruding radially outward is provided on the outer surface of the inner cylinder forward of the outer fitting portion, and the abutment wall portion is preferably provided at the rear end of the flange portion.

前記第4の発明の熱変色性筆記具は、前記構成により、内筒体を外筒体内へ挿入する際、外径の大きい鍔部が引っかかって内側嵌合部に傷が付くことを防ぐことができる。また、外径の大きい鍔部が外側嵌合部より前方に設けられているため、内筒体の外筒体内への挿入性が向上する。 The thermochromic writing instrument of the fourth invention, with the above-mentioned configuration, can prevent the flange with a large outer diameter from getting caught and damaging the inner fitting portion when inserting the inner cylinder into the outer cylinder. In addition, since the flange with a large outer diameter is located forward of the outer fitting portion, the insertability of the inner cylinder into the outer cylinder is improved.

本発明の熱変色性筆記具によれば、内側嵌合部に傷が付くことを防ぎ、内筒体と外筒体との嵌合性能を確実に確保することができることに加え、内筒体の外筒体内への挿入性が向上する。 The thermochromic writing instrument of the present invention prevents scratches on the inner fitting portion, reliably ensures the fitting performance between the inner and outer barrels, and improves the insertability of the inner barrel into the outer barrel.

本発明の第1の実施の形態を示す縦断面図である。1 is a vertical cross-sectional view showing a first embodiment of the present invention. 図1の要部拡大縦断面図である。FIG. 2 is an enlarged longitudinal sectional view of a main portion of FIG. 1 . 図2のA‐A線断面図である。FIG. 3 is a cross-sectional view taken along line A-A of FIG. 2 . 図1において内筒体及び摩擦体を固着した外筒体の縦断面図である。FIG. 2 is a vertical cross-sectional view of the outer cylindrical body to which the inner cylindrical body and the friction body are fixed in FIG. 1 . 図1の変形例を示す要部拡大縦断面図である。FIG. 2 is an enlarged longitudinal sectional view of a main portion showing a modification of FIG. 1 . 本発明の第2実施形態を示す要部拡大縦断面図である。二点鎖線は筆記具本体を示す。1 is an enlarged longitudinal sectional view showing a main part of a second embodiment of the present invention, in which the two-dot chain line indicates a writing instrument body. 図6の変形例を示す要部拡大縦断面図である。FIG. 7 is an enlarged longitudinal sectional view of a main portion showing a modification of FIG. 6 .

<第1実施形態>
図1乃至図5に本発明の第1実施形態を示す。本実施の形態の熱変色性筆記具1は、ペン先21と、該ペン先21が固着されるペン先保持筒3と、該ペン先保持筒3の後端と接続される外筒体4と、該外筒体4の後端開口部42に固着される摩擦体6と、該摩擦体6前方の外筒体4の内面に固着される内筒体5と、該内筒体5前方の外筒体4内部及びペン先保持筒3内部に収容されるインキ吸蔵体22と、を備えた筆記具本体2からなる。
First Embodiment
1 to 5 show a first embodiment of the present invention. A thermochromic writing implement 1 of this embodiment comprises a writing implement body 2 including a pen tip 21, a pen tip holding tube 3 to which the pen tip 21 is fixed, an outer cylinder 4 connected to the rear end of the pen tip holding tube 3, a friction body 6 fixed to a rear end opening 42 of the outer cylinder 4, an inner cylinder 5 fixed to the inner surface of the outer cylinder 4 in front of the friction body 6, and an ink occlusion body 22 accommodated inside the outer cylinder 4 and inside the pen tip holding tube 3 in front of the inner cylinder 5.

・ペン先
前記ペン先21は、繊維の樹脂加工体からなる。前記ペン先21は、これ以外にも、例えば、ボールペンチップ、繊維束の熱融着加工体、フェルト加工体、パイプ状ペン体、先端にスリットを有する万年筆型板状ペン体、毛筆ペン体、合成樹脂の多孔質気泡体、軸方向のインキ誘導路を有する合成樹脂の押出成形体等が挙げられる。
Pen tip The pen tip 21 is made of a resin-processed fiber body. Other examples of the pen tip 21 include a ballpoint pen tip, a heat-fused fiber bundle body, a felt body, a pipe-shaped pen body, a fountain pen-type flat pen body having a slit at the tip, a brush pen body, a synthetic resin porous foam body, and a synthetic resin extrusion molded body having an axial ink guide path.

・インキ吸蔵体
前記インキ吸蔵体22は、インキを含浸可能な連続気孔を有する部材(即ち多孔質材料)からなるものであればよく、例えば、繊維束の熱融着加工体、繊維束の樹脂加工体、フェルトの樹脂加工体、フェルトのニードルパンチ加工体、合成樹脂の連続気泡体等が挙げられる。また、前記インキ吸蔵体22は、その外周面に合成樹脂フィルム等よりなる外皮を備える構成でもよい。尚、前記インキ吸蔵体22の前面にペン先21の後端部が突き刺し接続される。
Ink Occluder The ink occluder 22 may be any material having continuous pores that can be impregnated with ink (i.e., a porous material), such as a heat-sealed fiber bundle, a resin-processed fiber bundle, a resin-processed felt, a needle-punched felt, or an open-celled synthetic resin. The ink occluder 22 may also be provided with an outer skin made of a synthetic resin film or the like on its outer periphery. The rear end of the pen tip 21 is pierced and connected to the front surface of the ink occluder 22.

インキ吸蔵体22には熱変色性インキが含浸される。前記熱変色性インキによって形成された筆跡は、摩擦体6の後端で摩擦することにより変色可能である。 The ink occlusion body 22 is impregnated with thermochromic ink. The handwriting formed with the thermochromic ink can be discolored by rubbing it with the rear end of the friction body 6.

・ペン先保持筒
前記ペン先保持筒3は、合成樹脂の射出成形により得られる。前記ペン先保持筒3は、先細形状の前端部にペン先21が圧入固着され、先細形状の前端部より前方にペン先21の前端が突出される。前記ペン先保持筒3の内部に、インキ吸蔵体22の前部が収容され、前記インキ吸蔵体22の前端にペン先21の後端が突き刺し接続される。前記ペン先保持筒3の後端開口部は、外筒体4の前端開口部41と気密嵌合により接続される。前記ペン先21外面とペン先保持筒3内面との間には、ペン先保持筒3内部と外気との連通が可能な通気路(図示せず)が形成される。
Pen tip holding tube The pen tip holding tube 3 is obtained by injection molding of synthetic resin. The pen tip 21 is press-fitted and fixed to the tapered front end of the pen tip holding tube 3, and the front end of the pen tip 21 protrudes forward from the tapered front end. The front part of the ink absorbing body 22 is housed inside the pen tip holding tube 3, and the rear end of the pen tip 21 is inserted and connected to the front end of the ink absorbing body 22. The rear end opening of the pen tip holding tube 3 is connected to the front end opening 41 of the outer cylinder 4 by airtight fitting. Between the outer surface of the pen tip 21 and the inner surface of the pen tip holding tube 3, an air passage (not shown) is formed that allows communication between the inside of the pen tip holding tube 3 and the outside air.

・外筒体
前記外筒体4は、合成樹脂の射出成形より得られる円筒体からなる。前記外筒体4は、内孔が軸方向に貫通され、前記内孔が前端開口部41及び後端開口部42より外部に連通される。前記外筒体4の前端開口部41の内面は、ペン先保持筒3の後端開口部42の外面と気密嵌合により接続される。
External cylinder body The external cylinder body 4 is a cylinder obtained by injection molding of synthetic resin. The external cylinder body 4 has an inner hole penetrating in the axial direction, and the inner hole communicates with the outside through a front end opening 41 and a rear end opening 42. The inner surface of the front end opening 41 of the external cylinder body 4 is connected to the outer surface of the rear end opening 42 of the pen tip holding tube 3 by airtight fitting.

外筒体4の後部の内面には、環状の内側嵌合部43が形成される。前記内側嵌合部43は、環状平滑面又は環状突起からなる。内側嵌合部43の内径Cは外筒体4の内径Bより小さく設定される。 A ring-shaped inner fitting portion 43 is formed on the inner surface of the rear part of the outer cylinder body 4. The inner fitting portion 43 is made of a ring-shaped smooth surface or a ring-shaped protrusion. The inner diameter C of the inner fitting portion 43 is set to be smaller than the inner diameter B of the outer cylinder body 4.

前記外筒体4の内面には規制壁部44が一体に形成される。前記規制壁部44は外筒体4の内面と内側嵌合部43との間に生じる環状の段差からなる。規制壁部44の前端面は、軸線に対して垂直に形成される。 A restricting wall portion 44 is integrally formed on the inner surface of the outer cylinder body 4. The restricting wall portion 44 is an annular step that occurs between the inner surface of the outer cylinder body 4 and the inner fitting portion 43. The front end surface of the restricting wall portion 44 is formed perpendicular to the axis.

前記規制壁部44の後方の外筒体4内面(即ち外筒体4の後端開口部42内面)には、内向突起45が一体に形成される。前記内向突起45は環状突起又は複数個の分散状突起からなる。前記内向突起45の内径(最小内径)Dは、内側嵌合部43の内径Cより小さく形成される。前記内向突起45の前端の角部は、鋭角又は直角に形成される。前記内向突起45の後面は、後方に向かい内径が次第に大きくなる傾斜面を有する。 An inward protrusion 45 is integrally formed on the inner surface of the outer cylinder 4 behind the restricting wall portion 44 (i.e., the inner surface of the rear end opening 42 of the outer cylinder 4). The inward protrusion 45 is composed of an annular protrusion or multiple dispersed protrusions. The inner diameter (minimum inner diameter) D of the inward protrusion 45 is formed to be smaller than the inner diameter C of the inner fitting portion 43. The corner of the front end of the inward protrusion 45 is formed at an acute angle or a right angle. The rear surface of the inward protrusion 45 has an inclined surface whose inner diameter gradually increases toward the rear.

尚、本実施形態において、外筒体4は、少なくとも筆記具本体2の後端部を構成するものであればよく、外筒体4が筆記具本体2の略全体を構成するものでもよいし、外筒体4が筆記具本体の後端部のみを構成するものでもよい。また、本発明において、外筒体4をペン先21に固定する構成は、例えば、外筒体4にペン先21を直接固定する構成、又は外筒体4にペン先保持筒3等の他の部材を介してペン先21を固定する構成が挙げられる。 In this embodiment, the outer cylinder 4 only needs to constitute at least the rear end of the writing instrument body 2, and the outer cylinder 4 may constitute substantially the entire writing instrument body 2, or the outer cylinder 4 may constitute only the rear end of the writing instrument body. In addition, in the present invention, the configuration for fixing the outer cylinder 4 to the pen tip 21 may be, for example, a configuration in which the pen tip 21 is directly fixed to the outer cylinder 4, or a configuration in which the pen tip 21 is fixed to the outer cylinder 4 via another member such as the pen tip holding tube 3.

・内筒体
前記内筒体5は、前端が開口され且つ後端が閉鎖された、合成樹脂の射出成形により得られる有底円筒体である。前記内筒体5は、合成樹脂の射出成形により得られる。
The inner cylinder 5 is a bottomed cylinder having an open front end and a closed rear end, and is obtained by injection molding of a synthetic resin.

前記内筒体5の外面には、環状の外側嵌合部51が一体に形成される。前記外側嵌合部51は、環状突起又は環状平滑面よりなる。前記外側嵌合部51は、内側嵌合部43の内径Cより僅かに大きい外径を有する。それにより、外側嵌合部51と内側嵌合部43との確実な気密嵌合が得られる。 An annular outer fitting portion 51 is integrally formed on the outer surface of the inner cylinder 5. The outer fitting portion 51 is an annular protrusion or an annular smooth surface. The outer fitting portion 51 has an outer diameter slightly larger than the inner diameter C of the inner fitting portion 43. This ensures a reliable airtight fit between the outer fitting portion 51 and the inner fitting portion 43.

前記内筒体5の前端面には、前方に開口し且つ径方向に貫通する切り欠き52が形成される。前記内筒体5の前端面には、インキ吸蔵体22の後端面が当接される。前記切り欠き52により、インキ吸蔵体22の後端面と外気との通気が可能となる。 A notch 52 that opens forward and penetrates radially is formed in the front end surface of the inner cylinder 5. The rear end surface of the ink occlusion body 22 abuts against the front end surface of the inner cylinder 5. The notch 52 allows ventilation between the rear end surface of the ink occlusion body 22 and the outside air.

外側嵌合部51より前方の内筒体5の外面には、径方向外方に突出する鍔部53が設けられている。鍔部53は環状突起又は複数個の分散状突起からなる。鍔部53の外径は外筒体4の内径Bと同じ、又は内径Bより小さく設定される。鍔部53の後端には当接壁部54が一体に形成される。当接壁部54は、軸線に対して垂直面となっている。当接壁部54の後端の外径は、外側嵌合部51の外径より大きく設定される。 A flange 53 protruding radially outward is provided on the outer surface of the inner cylinder 5 forward of the outer fitting portion 51. The flange 53 consists of an annular protrusion or multiple dispersed protrusions. The outer diameter of the flange 53 is set to be the same as or smaller than the inner diameter B of the outer cylinder 4. An abutment wall 54 is integrally formed with the rear end of the flange 53. The abutment wall 54 is a surface perpendicular to the axis. The outer diameter of the rear end of the abutment wall 54 is set to be larger than the outer diameter of the outer fitting portion 51.

外側嵌合部51より後方の内筒体5の外径は後方に向かうにつれて徐々に小さくなっている。本実施の形態において、内筒体5の後端は切頭円錐形状である。内筒体5の外径が後方に向かうにつれて小さくなっていることにより、内筒体5の外筒体4内への挿入性が向上する。 The outer diameter of the inner cylinder 5 rearward from the outer fitting portion 51 gradually decreases toward the rear. In this embodiment, the rear end of the inner cylinder 5 has a truncated cone shape. Since the outer diameter of the inner cylinder 5 decreases toward the rear, the insertability of the inner cylinder 5 into the outer cylinder 4 is improved.

規制壁部44は後方に向かうにつれて内径が徐々に小さくなる形状であってもよい。図5に示すように、規制壁部44をテーパ形状とすることにより、内筒体5の外筒体4内への挿入性がさらに向上する。規制壁部44をテーパ形状とした場合、規制壁部44と鍔部53とは線接触して当接する。 The restricting wall portion 44 may be shaped so that the inner diameter gradually decreases toward the rear. As shown in FIG. 5, by making the restricting wall portion 44 tapered, the insertability of the inner cylinder body 5 into the outer cylinder body 4 is further improved. When the restricting wall portion 44 is tapered, the restricting wall portion 44 and the flange portion 53 abut in a line contact.

・摩擦体
前記摩擦体6は、大径部と、大径部の前方に一体に連設される小径部とからなり、弾性材料により一体に形成される。前記摩擦体6は、合成ゴムやエラストマー等の弾性材料により形成される。本実施の形態では、前記摩擦体6は、熱変色性インキによって形成された筆跡の表面を擦って該筆跡を熱変色させる摩擦変色部材が採用される。前記弾性材料からなる摩擦体6は、これ以外にも、消しゴム等が挙げられる。前記摩擦体6は、外筒体4の後端開口部に後方から前方に向かって挿着される。
Friction body The friction body 6 is composed of a large diameter portion and a small diameter portion that is integrally connected to the front of the large diameter portion, and is integrally formed from an elastic material. The friction body 6 is formed from an elastic material such as synthetic rubber or elastomer. In this embodiment, a friction-discoloring member that rubs the surface of handwriting formed with thermochromic ink to thermally discolor the handwriting is used as the friction body 6. Other examples of the friction body 6 made of elastic material include erasers. The friction body 6 is inserted into the rear end opening of the outer cylinder 4 from the rear toward the front.

前記大径部の後面は凸曲面状を有する。前記大径部の前端には、外筒体4の後端開口部42の開口端(具体的には外筒体4の後端)に当接可能な肩部が形成される。前記大径部の最大外径は、外筒体4の後端開口部42の内径よりも大きく且つ外筒体4の後端の外径よりも小さく設定される。 The rear surface of the large diameter portion has a convex curved shape. A shoulder portion is formed at the front end of the large diameter portion so as to be able to abut against the open end of the rear end opening 42 of the outer cylinder 4 (specifically, the rear end of the outer cylinder 4). The maximum outer diameter of the large diameter portion is set to be larger than the inner diameter of the rear end opening 42 of the outer cylinder 4 and smaller than the outer diameter of the rear end of the outer cylinder 4.

前記小径部の前端部の外周面には環状の外向突起61が一体に形成される。前記外向突起61の前面は、後方に向かうに従い外径が次第に大きくなる傾斜面(即ち円錐面)を有する。前記外向突起61の後端は、直角又は鋭角の角部を有する。 An annular outward protrusion 61 is integrally formed on the outer circumferential surface of the front end of the small diameter portion. The front surface of the outward protrusion 61 has an inclined surface (i.e., a conical surface) whose outer diameter gradually increases toward the rear. The rear end of the outward protrusion 61 has a right-angled or acute-angled corner.

前記外向突起61の外径(最大外径)は、内向突起45の内径D(最小内径)より大きく形成され、外向突起61と内向突起45とが確実な抜け止め係止が可能となる。前記外向突起61の外径(最大外径)は、内向突起45後方の外筒体4の後端開口部42の内径よりも小さく形成され、それにより、外向突起61と内向突起45後方の外筒体4の後端開口部内面とが非嵌合状態に維持され、外向突起61が内向突起45を乗り越える直前までの摩擦体6の円滑な挿入が可能となる。前記摩擦体6の外筒体4の後端開口部42への挿着が終了した状態(乗り越え嵌合が終了した状態)で、外向突起61後方の摩擦体6の外面と内向突起45が嵌合する。 The outer diameter (maximum outer diameter) of the outward protrusion 61 is formed larger than the inner diameter D (minimum inner diameter) of the inward protrusion 45, so that the outward protrusion 61 and the inward protrusion 45 can be reliably locked and prevented from coming off. The outer diameter (maximum outer diameter) of the outward protrusion 61 is formed smaller than the inner diameter of the rear end opening 42 of the outer cylindrical body 4 behind the inward protrusion 45, so that the outward protrusion 61 and the inner surface of the rear end opening of the outer cylindrical body 4 behind the inward protrusion 45 are maintained in a non-engaged state, and the friction body 6 can be smoothly inserted until just before the outward protrusion 61 rides over the inward protrusion 45. When the friction body 6 is completely inserted into the rear end opening 42 of the outer cylindrical body 4 (when the over-engagement is completed), the outer surface of the friction body 6 behind the outward protrusion 61 and the inward protrusion 45 are engaged.

摩擦体6の外筒体4の後端開口部42への挿着が終了した状態(乗り越え嵌合が終了した状態)で、外向突起61の後端(即ち最大外径部)が内向突起45の前端(即ち最小内径部)よりも前方に位置し、内向突起45の前端と外向突起61の後端との間に、軸方向の隙間が形成される。それにより、外向突起61が内向突起45を後方から前方に乗り越える時、外向突起61と内向突起45との滑りが悪くても、外向突起61が内向突起45を確実に乗り越えることができる。 When the friction body 6 has been completely inserted into the rear end opening 42 of the outer tube body 4 (when the over-riding fit has been completed), the rear end of the outward projection 61 (i.e., the maximum outer diameter portion) is located forward of the front end of the inward projection 45 (i.e., the minimum inner diameter portion), and an axial gap is formed between the front end of the inward projection 45 and the rear end of the outward projection 61. As a result, when the outward projection 61 rides over the inward projection 45 from rear to front, the outward projection 61 can reliably ride over the inward projection 45 even if the sliding between the outward projection 61 and the inward projection 45 is poor.

また、摩擦体6の外筒体4の後端開口部42への挿着が終了した状態(乗り越え嵌合が終了した状態)で、外向突起61の外面と、外筒体4の内面との間には、径方向の隙間が形成される。それにより、外向突起61が内向突起45を後方から前方に乗り越える時、外向突起61と内向突起45との滑りが悪くても、外向突起61が内向突起45を確実に乗り越えることができる。 In addition, when the friction body 6 is completely inserted into the rear end opening 42 of the outer cylindrical body 4 (when the over-riding fitting is complete), a radial gap is formed between the outer surface of the outward protrusion 61 and the inner surface of the outer cylindrical body 4. As a result, when the outward protrusion 61 rides over the inward protrusion 45 from rear to front, even if the outward protrusion 61 and the inward protrusion 45 do not slide easily, the outward protrusion 61 can reliably ride over the inward protrusion 45.

本実施の形態の熱変色性筆記具1は、熱変色性インキが内蔵され且つ該インキが吐出可能なペン先21を備える筆記具本体2又は筆記具本体2のペン先21に取り付け可能なキャップ本体7を備え、筆記具本体2又はキャップ本体7に取り付けられ、前記熱変色性インキの筆跡を摩擦する摩擦体6を備えた熱変色性筆記具であって、筆記具本体2又はキャップ本体7が、外筒体4と、該外筒体4の内面に嵌着される内筒体5とを備え、外筒体4の後端には摩擦体6が装着され、内筒体5の外面には外側嵌合部51が形成され、外筒体4の内面に外側嵌合部51と嵌合する内側嵌合部43が形成され、内筒体5の外面には後方に面する当接壁部54が形成され、外筒体4の内面には当接壁部54と前後方向に当接し且つ内筒体5の後方への移動を阻止する規制壁部44が一体に形成され、規制壁部44は内側嵌合部43より前方に設けられていることにより、内筒体5を外筒体4内へ挿入する際に内筒体5が外筒体4の内面に引っかかって内側嵌合部43に傷が付くことを防ぐことができる。また、内側嵌合部43より前方の規制壁部44によって内筒体5の移動を規制するため、内筒体5の外側嵌合部51より後方の外径を任意に設定することができ、内筒体5の外筒体4内への挿入性が向上する。 The thermochromic writing instrument 1 of this embodiment is a thermochromic writing instrument that includes a writing instrument body 2 having a pen tip 21 capable of discharging thermochromic ink, or a cap body 7 that can be attached to the pen tip 21 of the writing instrument body 2, and is attached to the writing instrument body 2 or the cap body 7 and has a friction body 6 that rubs the handwriting of the thermochromic ink. The writing instrument body 2 or the cap body 7 includes an outer tube 4 and an inner tube 5 that is fitted to the inner surface of the outer tube 4, a friction body 6 is attached to the rear end of the outer tube 4, and a friction body 6 is attached to the outer surface of the inner tube 5. The outer fitting portion 51 is formed, the inner surface of the outer cylinder 4 is formed with an inner fitting portion 43 that fits with the outer fitting portion 51, the outer surface of the inner cylinder 5 is formed with a rearward-facing abutment wall portion 54, and the inner surface of the outer cylinder 4 is integrally formed with a regulating wall portion 44 that abuts against the abutment wall portion 54 in the front-rear direction and prevents the inner cylinder 5 from moving rearward. The regulating wall portion 44 is provided forward of the inner fitting portion 43, so that when the inner cylinder 5 is inserted into the outer cylinder 4, the inner fitting portion 43 can be prevented from being scratched by the inner surface of the outer cylinder 4. In addition, since the regulating wall portion 44 forward of the inner fitting portion 43 restricts the movement of the inner cylinder 5, the outer diameter of the inner cylinder 5 rearward of the outer fitting portion 51 can be set arbitrarily, improving the insertability of the inner cylinder 5 into the outer cylinder 4.

本実施の形態の熱変色性筆記具1は、熱変色性インキが内蔵され且つ該インキが吐出可能なペン先21を備える筆記具本体2又は筆記具本体2のペン先21に取り付け可能なキャップ本体7を備え、筆記具本体2又はキャップ本体7に取り付けられ、前記熱変色性インキの筆跡を摩擦する摩擦体6を備えた熱変色性筆記具であって、筆記具本体2又はキャップ本体7が、外筒体4と、該外筒体4の内面に嵌着される内筒体5とを備え、外筒体4が、前後方向に貫通する内孔と、該内孔に連通する前端開口部41及び後端開口部42とを備え、外筒体4の後端開口部42には前記摩擦体が装着され、内筒体5の外面には外側嵌合部51が形成され、外筒体4の内面に外側嵌合部51と気密嵌合する内側嵌合部43が形成され、内筒体5の外面には後方に面する当接壁部54が形成され、外筒体4の内面には当接壁部54と前後方向に当接し且つ内筒体5の後方への移動を阻止する規制壁部44が一体に形成され、規制壁部44は内側嵌合部43より前方に設けられていることにより、内筒体5を外筒体4内へ挿入する際に内筒体5が外筒体4の内面に引っかかって内側嵌合部43に傷が付くことを防ぎ、内筒体5外面と外筒体4内面との気密を確実に確保することができる。また、内側嵌合部43より前方の規制壁部44によって内筒体5の移動を規制するため、内筒体5の後端の外径を任意に設定することができ、内筒体5の外筒体4内への挿入性が向上する。 The thermochromic writing instrument 1 of this embodiment is a thermochromic writing instrument that includes a writing instrument body 2 having a pen tip 21 that contains thermochromic ink and can eject the ink, or a cap body 7 that can be attached to the pen tip 21 of the writing instrument body 2, and is attached to the writing instrument body 2 or the cap body 7 and includes a friction body 6 that rubs the handwriting of the thermochromic ink. The writing instrument body 2 or the cap body 7 includes an outer tube 4 and an inner tube 5 that is fitted to the inner surface of the outer tube 4, the outer tube 4 has an inner hole that penetrates in the front-to-rear direction, and a front end opening 41 and a rear end opening 42 that communicate with the inner hole, and the rear end opening 42 of the outer tube 4 is provided with the friction body. The outer surface of the inner cylinder 5 is formed with an outer fitting portion 51, the inner surface of the outer cylinder 4 is formed with an inner fitting portion 43 that fits airtight with the outer fitting portion 51, the outer surface of the inner cylinder 5 is formed with a rearward-facing abutment wall portion 54, and the inner surface of the outer cylinder 4 is integrally formed with a regulating wall portion 44 that abuts against the abutment wall portion 54 in the front-rear direction and prevents the inner cylinder 5 from moving rearward. The regulating wall portion 44 is provided forward of the inner fitting portion 43, so that when the inner cylinder 5 is inserted into the outer cylinder 4, the inner fitting portion 43 is prevented from being scratched by the inner surface of the outer cylinder 4, and airtightness between the outer surface of the inner cylinder 5 and the inner surface of the outer cylinder 4 can be reliably ensured. In addition, since the regulating wall portion 44 forward of the inner fitting portion 43 restricts the movement of the inner cylinder 5, the outer diameter of the rear end of the inner cylinder 5 can be set arbitrarily, improving the insertability of the inner cylinder 5 into the outer cylinder 4.

本実施の形態の熱変色性筆記具1は、外側嵌合部51より前方の内筒体5の外面には径方向外方に突出する鍔部53が設けられており、鍔部53の後端に当接壁部54が設けられていることにより、内筒体5を外筒体4内へ挿入する際、外径の大きい鍔部53が引っかかって内側嵌合部43に傷が付くことを防ぐことができる。また、外径の大きい鍔部53が外側嵌合部51より前方に設けられているため、内筒体5の外筒体4内への挿入性が向上する。 The thermochromic writing instrument 1 of this embodiment has a flange 53 that protrudes radially outward on the outer surface of the inner cylinder 5 forward of the outer fitting 51, and an abutment wall 54 is provided at the rear end of the flange 53, which prevents the flange 53, which has a larger outer diameter, from getting caught and scratching the inner fitting 43 when the inner cylinder 5 is inserted into the outer cylinder 4. In addition, because the flange 53, which has a larger outer diameter, is provided forward of the outer fitting 51, the insertability of the inner cylinder 5 into the outer cylinder 4 is improved.

<第2実施形態>
図6乃至図8に本発明の第2実施形態を示す。本実施の形態の熱変色性筆記具1は、外筒体4と、該外筒体4の後端開口部42に固着される摩擦体6と、該摩擦体6前方の外筒体4の内面に固着される内筒体5と、を備えたキャップ本体7からなる。
Second Embodiment
6 to 8 show a second embodiment of the present invention. The thermochromic writing instrument 1 of this embodiment comprises a cap body 7 including an outer cylinder 4, a friction body 6 fixed to the rear end opening 42 of the outer cylinder 4, and an inner cylinder 5 fixed to the inner surface of the outer cylinder 4 in front of the friction body 6.

・外筒体
前記外筒体4は、合成樹脂の射出成形より得られる円筒体からなる。前記外筒体4は、内孔が軸方向に貫通され、前記内孔が前端開口部41及び後端開口部42より外部に連通される。
The outer cylinder 4 is a cylindrical body obtained by injection molding of synthetic resin. The outer cylinder 4 has an inner hole passing through it in the axial direction, and the inner hole communicates with the outside through a front end opening 41 and a rear end opening 42.

外筒体4の後部の内面には、環状の内側嵌合部43が形成される。前記内側嵌合部43は、環状平滑面又は環状突起からなる。内側嵌合部43の内径Cは外筒体4の内径Bより小さく設定される。 A ring-shaped inner fitting portion 43 is formed on the inner surface of the rear part of the outer cylinder body 4. The inner fitting portion 43 is made of a ring-shaped smooth surface or a ring-shaped protrusion. The inner diameter C of the inner fitting portion 43 is set to be smaller than the inner diameter B of the outer cylinder body 4.

前記外筒体4の内面には規制壁部44が一体に形成される。前記規制壁部44は外筒体4の内面と内側嵌合部43との間に生じる環状の段差からなる。規制壁部44の前端面は、軸線に対して垂直に形成される。 A restricting wall portion 44 is integrally formed on the inner surface of the outer cylinder body 4. The restricting wall portion 44 is an annular step that occurs between the inner surface of the outer cylinder body 4 and the inner fitting portion 43. The front end surface of the restricting wall portion 44 is formed perpendicular to the axis.

前記規制壁部44の後方の外筒体4内面(即ち外筒体4の後端開口部42内面)には、内向突起45が一体に形成される。前記内向突起45は環状突起又は複数個の分散状突起からなる。前記内向突起45の内径(最小内径)Dは、内側嵌合部43の内径Cより小さく形成される。前記内向突起45の前端の角部は、鋭角又は直角に形成される。前記内向突起45の後面は、後方に向かい内径が次第に大きくなる傾斜面を有する。 An inward protrusion 45 is integrally formed on the inner surface of the outer cylinder 4 behind the restricting wall portion 44 (i.e., the inner surface of the rear end opening 42 of the outer cylinder 4). The inward protrusion 45 is composed of an annular protrusion or multiple dispersed protrusions. The inner diameter (minimum inner diameter) D of the inward protrusion 45 is formed to be smaller than the inner diameter C of the inner fitting portion 43. The corner of the front end of the inward protrusion 45 is formed at an acute angle or a right angle. The rear surface of the inward protrusion 45 has an inclined surface whose inner diameter gradually increases toward the rear.

・内筒体
前記内筒体5は、前端が開口され且つ後端が閉鎖された、合成樹脂の射出成形により得られる有底円筒体である。前記内筒体5は、合成樹脂の射出成形により得られる。
The inner cylinder 5 is a bottomed cylinder having an open front end and a closed rear end, and is obtained by injection molding of a synthetic resin.

前記内筒体5の外面(内筒体5の大外径部の外面)には、環状の外側嵌合部51が一体に形成される。前記外側嵌合部51は、環状突起又は複数の分散状突起よりなる。前記外側嵌合部51は、内側嵌合部43の内径Cより僅かに大きい外径を有する。図6に示すように、内側嵌合部43が環状突起からなる場合、内筒体5は外筒体4に対して乗り越え嵌合によって固着される。内側嵌合部43が環状平滑面からなる場合、内筒体5は外筒体4に対して圧入嵌合によって固着される。 An annular outer fitting portion 51 is integrally formed on the outer surface of the inner cylinder 5 (the outer surface of the large outer diameter portion of the inner cylinder 5). The outer fitting portion 51 consists of an annular protrusion or multiple dispersed protrusions. The outer fitting portion 51 has an outer diameter slightly larger than the inner diameter C of the inner fitting portion 43. As shown in FIG. 6, when the inner fitting portion 43 consists of an annular protrusion, the inner cylinder 5 is fixed to the outer cylinder 4 by a jump fit. When the inner fitting portion 43 consists of an annular smooth surface, the inner cylinder 5 is fixed to the outer cylinder 4 by a press fit.

外側嵌合部51より前方の内筒体5の外面には、径方向外方に突出する鍔部53が設けられている。鍔部53は環状突起又は複数個の分散状突起からなる。鍔部53の外径は外筒体4の内径Bと同じ、又は内径Bより小さく設定される。本実施形態では、鍔部53の外径を内径Bと略同一とすることにより、内筒体5の径方向の安定性が向上する。鍔部53の外径を内径Bと略同一であっても、内側嵌合部43が規制壁部44より後方に設けられているため、鍔部53によって内側嵌合部43が傷つくことがない。鍔部53の後端には当接壁部54が一体に形成される。当接壁部54は、軸線に対して垂直面となっている。当接壁部54の後端の外径は、外側嵌合部51の外径より大きく設定される。 The outer surface of the inner cylinder 5 forward of the outer fitting portion 51 is provided with a flange portion 53 that protrudes radially outward. The flange portion 53 is made of an annular protrusion or multiple dispersed protrusions. The outer diameter of the flange portion 53 is set to be the same as the inner diameter B of the outer cylinder 4 or smaller than the inner diameter B. In this embodiment, the outer diameter of the flange portion 53 is set to be approximately the same as the inner diameter B, thereby improving the radial stability of the inner cylinder 5. Even if the outer diameter of the flange portion 53 is approximately the same as the inner diameter B, the inner fitting portion 43 is not damaged by the flange portion 53 because the inner fitting portion 43 is provided behind the regulating wall portion 44. The abutment wall portion 54 is integrally formed with the rear end of the flange portion 53. The abutment wall portion 54 is a surface perpendicular to the axis. The outer diameter of the rear end of the abutment wall portion 54 is set to be larger than the outer diameter of the outer fitting portion 51.

図6において、外側嵌合部51から鍔部53までの軸方向の距離は、内側嵌合部43から規制壁部44までの軸方向の距離より僅かに大きく設定される。前記構成により、外筒体4内に内筒体5を挿入する際、外側嵌合部51が内側嵌合部43を乗り越え嵌合した後に鍔部53と規制壁部44とが当接し、内筒体5が外筒体4内の所定の位置に固着される。 In FIG. 6, the axial distance from the outer fitting portion 51 to the flange portion 53 is set to be slightly larger than the axial distance from the inner fitting portion 43 to the regulating wall portion 44. With this configuration, when the inner cylinder 5 is inserted into the outer cylinder 4, the outer fitting portion 51 overcomes and fits over the inner fitting portion 43, and then the flange portion 53 and the regulating wall portion 44 come into contact, and the inner cylinder 5 is fixed at a predetermined position within the outer cylinder 4.

前記内筒体5の前端の内面には、筆記具本体2の外面と気密嵌合する環状シール部55が形成される。環状シール部55は、環状突起又は環状平滑面よりなる。環状シール部55は径方向に変形可能に構成するため、外側嵌合部51及び鍔部53は環状シール部55より後方に設けられる。 The inner surface of the front end of the inner cylinder 5 is formed with an annular seal portion 55 that fits airtightly with the outer surface of the writing instrument body 2. The annular seal portion 55 is made of an annular protrusion or an annular smooth surface. The annular seal portion 55 is configured to be deformable in the radial direction, so the outer fitting portion 51 and the flange portion 53 are provided behind the annular seal portion 55.

外側嵌合部51より後方の内筒体5の外径は後方に向かうにつれて徐々に小さくなっている。本実施の形態において、内筒体5の後端は切頭円錐形状である。内筒体5の外径が後方に向かうにつれて小さくなっていることにより、内筒体5の外筒体4内への挿入性が向上する。 The outer diameter of the inner cylinder 5 rearward from the outer fitting portion 51 gradually decreases toward the rear. In this embodiment, the rear end of the inner cylinder 5 has a truncated cone shape. Since the outer diameter of the inner cylinder 5 decreases toward the rear, the insertability of the inner cylinder 5 into the outer cylinder 4 is improved.

規制壁部44は後方に向かうにつれて内径が徐々に小さくなる形状であってもよい。図7に示すように、規制壁部44をテーパ形状とすることにより、内筒体5の外筒体4内への挿入性がさらに向上する。規制壁部44をテーパ形状とした場合、規制壁部44と鍔部53とは線接触して当接する。 The restricting wall portion 44 may be shaped so that the inner diameter gradually decreases toward the rear. As shown in FIG. 7, by making the restricting wall portion 44 tapered, the insertability of the inner cylinder body 5 into the outer cylinder body 4 is further improved. When the restricting wall portion 44 is tapered, the restricting wall portion 44 and the flange portion 53 abut in a line contact.

・摩擦体
前記摩擦体6は、大径部と、大径部の前方に一体に連設される小径部とからなり、弾性材料により一体に形成される。前記摩擦体6は、合成ゴムやエラストマー等の弾性材料により形成される。本実施の形態では、前記摩擦体6は、熱変色性インキによって形成された筆跡の表面を擦って該筆跡を熱変色させる摩擦変色部材が採用される。前記弾性材料からなる摩擦体6は、これ以外にも、消しゴム等が挙げられる。前記摩擦体6は、外筒体4の後端開口部に後方から前方に向かって挿着される。
Friction body The friction body 6 is composed of a large diameter portion and a small diameter portion that is integrally connected to the front of the large diameter portion, and is integrally formed from an elastic material. The friction body 6 is formed from an elastic material such as synthetic rubber or elastomer. In this embodiment, a friction-discoloring member that rubs the surface of handwriting formed with thermochromic ink to thermally discolor the handwriting is used as the friction body 6. Other examples of the friction body 6 made of an elastic material include an eraser. The friction body 6 is inserted into the rear end opening of the outer cylinder body 4 from the rear toward the front.

前記大径部の後面は凸曲面状を有する。前記大径部の前端には、外筒体4の後端開口部42の開口端(具体的には外筒体4の後端)に当接可能な肩部が形成される。前記大径部の最大外径は、外筒体4の後端開口部42の内径よりも大きく且つ外筒体4の後端の外径よりも小さく設定される。 The rear surface of the large diameter portion has a convex curved shape. A shoulder portion is formed at the front end of the large diameter portion so as to be able to abut against the open end of the rear end opening 42 of the outer cylinder 4 (specifically, the rear end of the outer cylinder 4). The maximum outer diameter of the large diameter portion is set to be larger than the inner diameter of the rear end opening 42 of the outer cylinder 4 and smaller than the outer diameter of the rear end of the outer cylinder 4.

前記小径部の前端部の外周面には環状の外向突起61が一体に形成される。前記外向突起61の前面は、後方に向かうに従い外径が次第に大きくなる傾斜面(即ち円錐面)を有する。前記外向突起61の後端は、直角又は鋭角の角部を有する。 An annular outward protrusion 61 is integrally formed on the outer circumferential surface of the front end of the small diameter portion. The front surface of the outward protrusion 61 has an inclined surface (i.e., a conical surface) whose outer diameter gradually increases toward the rear. The rear end of the outward protrusion 61 has a right-angled or acute-angled corner.

前記外向突起61の外径(最大外径)は、内向突起45の内径D(最小内径)より大きく形成され、外向突起61と内向突起45とが確実な抜け止め係止が可能となる。前記外向突起61の外径(最大外径)は、内向突起45後方の外筒体4の後端開口部42の内径よりも小さく形成され、それにより、外向突起61と内向突起45後方の外筒体4の後端開口部内面とが非嵌合状態に維持され、外向突起61が内向突起45を乗り越える直前までの摩擦体6の円滑な挿入が可能となる。前記摩擦体6の外筒体4の後端開口部42への挿着が終了した状態(乗り越え嵌合が終了した状態)で、外向突起61後方の摩擦体6の外面と内向突起45が嵌合する。 The outer diameter (maximum outer diameter) of the outward protrusion 61 is formed larger than the inner diameter D (minimum inner diameter) of the inward protrusion 45, so that the outward protrusion 61 and the inward protrusion 45 can be reliably locked and prevented from coming off. The outer diameter (maximum outer diameter) of the outward protrusion 61 is formed smaller than the inner diameter of the rear end opening 42 of the outer cylindrical body 4 behind the inward protrusion 45, so that the outward protrusion 61 and the inner surface of the rear end opening of the outer cylindrical body 4 behind the inward protrusion 45 are maintained in a non-engaged state, and the friction body 6 can be smoothly inserted until just before the outward protrusion 61 rides over the inward protrusion 45. When the friction body 6 is completely inserted into the rear end opening 42 of the outer cylindrical body 4 (when the over-engagement is completed), the outer surface of the friction body 6 behind the outward protrusion 61 and the inward protrusion 45 are engaged.

摩擦体6の外筒体4の後端開口部42への挿着が終了した状態(乗り越え嵌合が終了した状態)で、外向突起61の後端(即ち最大外径部)が内向突起45の前端(即ち最小内径部)よりも前方に位置し、内向突起45の前端と外向突起61の後端との間に、軸方向の隙間が形成される。それにより、外向突起61が内向突起45を後方から前方に乗り越える時、外向突起61と内向突起45との滑りが悪くても、外向突起61が内向突起45を確実に乗り越えることができる。 When the friction body 6 has been completely inserted into the rear end opening 42 of the outer tube body 4 (when the over-riding fit has been completed), the rear end of the outward projection 61 (i.e., the maximum outer diameter portion) is located forward of the front end of the inward projection 45 (i.e., the minimum inner diameter portion), and an axial gap is formed between the front end of the inward projection 45 and the rear end of the outward projection 61. As a result, when the outward projection 61 rides over the inward projection 45 from rear to front, the outward projection 61 can reliably ride over the inward projection 45 even if the sliding between the outward projection 61 and the inward projection 45 is poor.

また、摩擦体6の外筒体4の後端開口部42への挿着が終了した状態(乗り越え嵌合が終了した状態)で、外向突起61の外面と、外筒体4の内面との間には、径方向の隙間が形成される。それにより、外向突起61が内向突起45を後方から前方に乗り越える時、外向突起61と内向突起45との滑りが悪くても、外向突起61が内向突起45を確実に乗り越えることができる。 In addition, when the friction body 6 is completely inserted into the rear end opening 42 of the outer cylindrical body 4 (when the over-riding fitting is complete), a radial gap is formed between the outer surface of the outward protrusion 61 and the inner surface of the outer cylindrical body 4. As a result, when the outward protrusion 61 rides over the inward protrusion 45 from rear to front, even if the outward protrusion 61 and the inward protrusion 45 do not slide easily, the outward protrusion 61 can reliably ride over the inward protrusion 45.

本実施の形態の熱変色性筆記具1は、熱変色性インキが内蔵され且つ該インキが吐出可能なペン先21を備える筆記具本体2又は筆記具本体2のペン先21に取り付け可能なキャップ本体7を備え、筆記具本体2又はキャップ本体7に取り付けられ、前記熱変色性インキの筆跡を摩擦する摩擦体6を備えた熱変色性筆記具であって、筆記具本体2又はキャップ本体7が、外筒体4と、該外筒体4の内面に嵌着される内筒体5とを備え、外筒体4の後端には摩擦体6が装着され、内筒体5の外面には外側嵌合部51が形成され、外筒体4の内面に外側嵌合部51と嵌合する内側嵌合部43が形成され、内筒体5の外面には後方に面する当接壁部54が形成され、外筒体4の内面には当接壁部54と前後方向に当接し且つ内筒体5の後方への移動を阻止する規制壁部44が一体に形成され、規制壁部44は内側嵌合部43より前方に設けられていることにより、内筒体5を外筒体4内へ挿入する際に内筒体5が外筒体4の内面に引っかかって内側嵌合部43に傷が付くことを防ぐことができる。また、内側嵌合部43より前方の規制壁部44によって内筒体5の移動を規制するため、内筒体5の外側嵌合部51より後方の外径を任意に設定することができ、内筒体5の外筒体4内への挿入性が向上する。 The thermochromic writing instrument 1 of this embodiment is a thermochromic writing instrument that includes a writing instrument body 2 having a pen tip 21 capable of discharging thermochromic ink, or a cap body 7 that can be attached to the pen tip 21 of the writing instrument body 2, and is attached to the writing instrument body 2 or the cap body 7 and has a friction body 6 that rubs the handwriting of the thermochromic ink. The writing instrument body 2 or the cap body 7 includes an outer tube 4 and an inner tube 5 that is fitted to the inner surface of the outer tube 4, a friction body 6 is attached to the rear end of the outer tube 4, and a friction body 6 is attached to the outer surface of the inner tube 5. The outer fitting portion 51 is formed, the inner surface of the outer cylinder 4 is formed with an inner fitting portion 43 that fits with the outer fitting portion 51, the outer surface of the inner cylinder 5 is formed with a rearward-facing abutment wall portion 54, and the inner surface of the outer cylinder 4 is integrally formed with a regulating wall portion 44 that abuts against the abutment wall portion 54 in the front-rear direction and prevents the inner cylinder 5 from moving rearward. The regulating wall portion 44 is provided forward of the inner fitting portion 43, so that when the inner cylinder 5 is inserted into the outer cylinder 4, the inner fitting portion 43 can be prevented from being scratched by the inner surface of the outer cylinder 4. In addition, since the regulating wall portion 44 forward of the inner fitting portion 43 restricts the movement of the inner cylinder 5, the outer diameter of the inner cylinder 5 rearward of the outer fitting portion 51 can be set arbitrarily, improving the insertability of the inner cylinder 5 into the outer cylinder 4.

本実施の形態の熱変色性筆記具は、熱変色性インキが内蔵され且つ該インキが吐出可能なペン先21を備える筆記具本体2と、筆記具本体2のペン先21に取り付け可能なキャップ本体7と、キャップ本体7に取り付けられ、前記熱変色性インキの筆跡を摩擦する摩擦体6と、を備えた熱変色性筆記具であって、キャップ本体7が、外筒体4と、該外筒体4の内面に嵌着される内筒体5とを備え、外筒体4の後端には摩擦体6が装着され、内筒体5の外面には外側嵌合部51が形成され、外筒体4の内面に外側嵌合部51と嵌合する内側嵌合部43が形成され、内筒体5の外面には後方に面する当接壁部54が形成され、内側嵌合部43より前方の外筒体4の内面には当接壁部54と前後方向に当接し且つ内筒体5の後方への移動を阻止する規制壁部44が一体に形成され、内筒体5の内面の前端には筆記具本体2と気密嵌合する環状シール部55が設けられ、外側嵌合部51は当接壁部54より後方に設けられ、当接壁部54は環状シール部55より後方に設けられることにより、キャップ本体7のキャップとしての気密性能を維持しつつ、内筒体5を外筒体4内に挿入する際に内筒体5が外筒体4の内面に引っかかって内側嵌合部43に傷が付くことを防ぐことができる。 The thermochromic writing instrument of this embodiment is a thermochromic writing instrument comprising a writing instrument body 2 having a pen tip 21 in which thermochromic ink is built and capable of ejecting the ink, a cap body 7 that can be attached to the pen tip 21 of the writing instrument body 2, and a friction body 6 that is attached to the cap body 7 and rubs the handwriting of the thermochromic ink, and the cap body 7 comprises an outer tube 4 and an inner tube 5 that is fitted to the inner surface of the outer tube 4, the friction body 6 is attached to the rear end of the outer tube 4, an outer fitting portion 51 is formed on the outer surface of the inner tube 5, an inner fitting portion 43 that fits with the outer fitting portion 51 is formed on the inner surface of the outer tube 4, and a friction body 6 is attached to the outer surface of the inner tube 5 at the rear. A contact wall 54 is formed facing the outer cylinder 4, and a restricting wall 44 is integrally formed on the inner surface of the outer cylinder 4 forward of the inner fitting 43, which contacts the contact wall 54 in the front-rear direction and prevents the inner cylinder 5 from moving rearward. An annular seal 55 is provided at the front end of the inner surface of the inner cylinder 5, which fits airtightly with the writing instrument body 2. The outer fitting 51 is provided rearward of the contact wall 54, and the contact wall 54 is provided rearward of the annular seal 55. This maintains the airtight performance of the cap body 7 as a cap, while preventing the inner cylinder 5 from getting caught on the inner surface of the outer cylinder 4 and damaging the inner fitting 43 when the inner cylinder 5 is inserted into the outer cylinder 4.

本実施の形態の熱変色性筆記具1は、外側嵌合部51より前方の内筒体5の外面には径方向外方に突出する鍔部53が設けられており、鍔部53の後端に当接壁部54が設けられていることにより、内筒体5を外筒体4内へ挿入する際、外径の大きい鍔部53が引っかかって内側嵌合部43に傷が付くことを防ぐことができる。また、外径の大きい鍔部53が外側嵌合部51より前方に設けられているため、内筒体5の外筒体4内への挿入性が向上する。 The thermochromic writing instrument 1 of this embodiment has a flange 53 that protrudes radially outward on the outer surface of the inner cylinder 5 forward of the outer fitting 51, and an abutment wall 54 is provided at the rear end of the flange 53, which prevents the flange 53, which has a larger outer diameter, from getting caught and scratching the inner fitting 43 when the inner cylinder 5 is inserted into the outer cylinder 4. In addition, because the flange 53, which has a larger outer diameter, is provided forward of the outer fitting 51, the insertability of the inner cylinder 5 into the outer cylinder 4 is improved.

1 筆記具
2 筆記具本体
21 ペン先
22 インキ吸蔵体
3 ペン先保持筒
4 外筒体
41 前端開口部
42 後端開口部
43 内側嵌合部
44 規制壁部
45 内向突起
5 内筒体
51 外側嵌合部
52 切り欠き
53 鍔部
54 当接壁部
55 環状シール部
6 摩擦体
61 外向突起
7 キャップ本体
B 外筒体の内径
C 内側嵌合部の内径
D 内向突起の内径
Reference Signs List 1 Writing implement 2 Writing implement body 21 Pen tip 22 Ink occlusion body 3 Pen tip holding tube 4 Outer tube body 41 Front end opening 42 Rear end opening 43 Inner fitting portion 44 Regulating wall portion 45 Inward projection 5 Inner tube body 51 Outer fitting portion 52 Notch 53 Flange portion 54 Abutment wall portion 55 Annular seal portion 6 Friction body 61 Outward projection 7 Cap body B Inner diameter of outer tube body C Inner diameter of inner fitting portion D Inner diameter of inward projection

Claims (4)

熱変色性インキが内蔵され且つ該インキが吐出可能なペン先を備える筆記具本体又は前記筆記具本体の前記ペン先に取り付け可能なキャップ本体を備え、前記筆記具本体又は前記キャップ本体に取り付けられ、前記熱変色性インキの筆跡を摩擦する摩擦体を備えた熱変色性筆記具であって、
前記筆記具本体又は前記キャップ本体が、外筒体と、該外筒体の内面に嵌着される内筒体とを備え、
前記外筒体の後端には前記摩擦体が装着され、
前記内筒体の外面には外側嵌合部が形成され、前記外筒体の内面に前記外側嵌合部と嵌合する内側嵌合部が形成され、
前記内筒体の外面には後方に面する当接壁部が形成され、前記外筒体の内面には前記当接壁部と前後方向に当接し且つ前記内筒体の後方への移動を阻止する規制壁部が一体に形成され、前記規制壁部は前記内側嵌合部より前方に設けられていることを特徴とする熱変色性筆記具。
A thermochromic writing instrument comprising a writing instrument body having a thermochromic ink built therein and a pen tip capable of ejecting the ink, or a cap body that can be attached to the pen tip of the writing instrument body, and a friction body that is attached to the writing instrument body or the cap body and rubs the handwriting of the thermochromic ink,
The writing instrument body or the cap body includes an outer cylinder body and an inner cylinder body fitted to the inner surface of the outer cylinder body,
The friction body is attached to the rear end of the outer cylinder,
An outer fitting portion is formed on the outer surface of the inner cylinder, and an inner fitting portion that fits with the outer fitting portion is formed on the inner surface of the outer cylinder,
A thermochromic writing instrument characterized in that a rear-facing abutment wall portion is formed on the outer surface of the inner cylinder, and a regulating wall portion is integrally formed on the inner surface of the outer cylinder that abuts against the abutment wall portion in the front-to-rear direction and prevents the inner cylinder from moving rearward, and the regulating wall portion is located forward of the inner fitting portion.
熱変色性インキが内蔵され且つ該インキが吐出可能なペン先を備える筆記具本体又は前記筆記具本体の前記ペン先に取り付け可能なキャップ本体を備え、前記筆記具本体又は前記キャップ本体に取り付けられ、前記熱変色性インキの筆跡を摩擦する摩擦体を備えた熱変色性筆記具であって、
前記筆記具本体又は前記キャップ本体が、外筒体と、該外筒体の内面に嵌着される内筒体とを備え、
前記外筒体が、前後方向に貫通する内孔と、該内孔に連通する前端開口部及び後端開口部とを備え、
前記外筒体の前記後端開口部には前記摩擦体が装着され、
前記内筒体の外面には外側嵌合部が形成され、前記外筒体の内面に前記外側嵌合部と気密嵌合する内側嵌合部が形成され、
前記内筒体の外面には後方に面する当接壁部が形成され、前記外筒体の内面には前記当接壁部と前後方向に当接し且つ前記内筒体の後方への移動を阻止する規制壁部が一体に形成され、前記規制壁部は前記内側嵌合部より前方に設けられていることを特徴とする熱変色性筆記具。
A thermochromic writing instrument comprising a writing instrument body having a thermochromic ink built therein and a pen tip capable of ejecting the ink, or a cap body that can be attached to the pen tip of the writing instrument body, and a friction body that is attached to the writing instrument body or the cap body and rubs the handwriting of the thermochromic ink,
The writing instrument body or the cap body includes an outer cylinder body and an inner cylinder body fitted to the inner surface of the outer cylinder body,
the outer cylinder body has an inner hole penetrating in the front-rear direction, and a front end opening and a rear end opening communicating with the inner hole,
The friction body is attached to the rear end opening of the outer cylinder body,
An outer fitting portion is formed on an outer surface of the inner cylinder, and an inner fitting portion that fits airtightly with the outer fitting portion is formed on an inner surface of the outer cylinder,
A thermochromic writing instrument characterized in that a rear-facing abutment wall portion is formed on the outer surface of the inner cylinder, and a regulating wall portion is integrally formed on the inner surface of the outer cylinder that abuts against the abutment wall portion in the front-to-rear direction and prevents the inner cylinder from moving rearward, and the regulating wall portion is located forward of the inner fitting portion.
熱変色性インキが内蔵され且つ該インキが吐出可能なペン先を備える筆記具本体と、前記筆記具本体の前記ペン先に取り付け可能なキャップ本体と、前記キャップ本体に取り付けられ、前記熱変色性インキの筆跡を摩擦する摩擦体と、を備えた熱変色性筆記具であって、
前記キャップ本体が、外筒体と、該外筒体の内面に嵌着される内筒体とを備え、
前記外筒体の後端には前記摩擦体が装着され、
前記内筒体の外面には外側嵌合部が形成され、前記外筒体の内面に前記外側嵌合部と嵌合する内側嵌合部が形成され、
前記内筒体の外面には後方に面する当接壁部が形成され、前記内側嵌合部より前方の前記外筒体の内面には前記当接壁部と前後方向に当接し且つ前記内筒体の後方への移動を阻止する規制壁部が一体に形成され、
前記内筒体の内面の前端には前記筆記具本体と気密嵌合する環状シール部が設けられ、
前記外側嵌合部は前記当接壁部より後方に設けられ、前記当接壁部は前記環状シール部より後方に設けられることを特徴とする熱変色性筆記具。
A thermochromic writing instrument comprising: a writing instrument body having a thermochromic ink built therein and a pen tip capable of discharging the ink; a cap body that can be attached to the pen tip of the writing instrument body; and a friction body that is attached to the cap body and rubs the writing of the thermochromic ink,
The cap body includes an outer cylinder and an inner cylinder fitted to the inner surface of the outer cylinder,
The friction body is attached to the rear end of the outer cylinder,
An outer fitting portion is formed on the outer surface of the inner cylinder, and an inner fitting portion that fits with the outer fitting portion is formed on the inner surface of the outer cylinder,
a rearward-facing abutment wall portion is formed on an outer surface of the inner cylinder body, and a restricting wall portion is integrally formed on an inner surface of the outer cylinder body forward of the inner fitting portion, the restricting wall portion abutting against the abutment wall portion in the front-rear direction and preventing the inner cylinder body from moving rearward;
An annular seal portion is provided at the front end of the inner surface of the inner cylinder and is airtightly fitted with the writing instrument body,
A thermochromic writing implement, characterized in that the outer fitting portion is provided rearward of the abutment wall portion, and the abutment wall portion is provided rearward of the annular seal portion.
前記外側嵌合部より前方の前記内筒体の外面には径方向外方に突出する鍔部が設けられており、前記鍔部の後端に前記当接壁部が設けられていることを特徴とする請求項1乃至3の何れかに記載の熱変色性筆記具。 A thermochromic writing instrument according to any one of claims 1 to 3, characterized in that a flange protruding radially outward is provided on the outer surface of the inner cylinder forward of the outer fitting portion, and the abutment wall is provided at the rear end of the flange.
JP2022174964A 2022-10-31 2022-10-31 Thermochromic writing implements Pending JP2024065887A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2022174964A JP2024065887A (en) 2022-10-31 2022-10-31 Thermochromic writing implements

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2022174964A JP2024065887A (en) 2022-10-31 2022-10-31 Thermochromic writing implements

Publications (1)

Publication Number Publication Date
JP2024065887A true JP2024065887A (en) 2024-05-15

Family

ID=91065016

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2022174964A Pending JP2024065887A (en) 2022-10-31 2022-10-31 Thermochromic writing implements

Country Status (1)

Country Link
JP (1) JP2024065887A (en)

Similar Documents

Publication Publication Date Title
JP2011079206A (en) Thermochromic writing utensil
KR100763662B1 (en) Writing instrument
JP2024065887A (en) Thermochromic writing implements
JP2024077334A (en) Thermochromic writing implements
JP2005131943A (en) Pen point for pigment ink and writing utensil
JP2019181892A (en) Writing instrument
JP5340010B2 (en) Writing instrument and method for manufacturing the same
JP2011079205A (en) Thermochromic writing utensil
JP7370765B2 (en) writing implements
JP3629685B2 (en) Cap-type air tight writing instrument
JP2017056632A (en) Thermochromic writing instrument
JP2007030375A (en) Ball point pen
JP7118814B2 (en) ballpoint pen
JPH09263089A (en) Cap for writing implement or the like
JP2024073884A (en) Thermochromic writing implements
JP7253649B2 (en) writing instrument
US11667146B2 (en) Writing tool
JP7419591B2 (en) writing implements
JP2012006364A (en) Thermochromic writing utensil
JP2023094086A (en) Friction tool and friction tool manufacturing method
JP4550245B2 (en) Ballpoint pen
JP6155095B2 (en) Direct liquid writing instrument
JP2022182680A (en) Tail plug and writing instrument
JP2024066455A (en) Applicator
CN117083183A (en) Mounting structure in writing instrument, writing instrument and soft part