JP7618499B2

JP7618499B2 - Thermochromic writing implements

Info

Publication number: JP7618499B2
Application number: JP2021077319A
Authority: JP
Inventors: 嘉人光崎
Original assignee: Pilot Corp
Current assignee: Pilot Corp
Priority date: 2021-04-30
Filing date: 2021-04-30
Publication date: 2025-01-21
Anticipated expiration: 2041-04-30
Also published as: JP2022170988A

Description

本発明は、熱変色性筆記具に関する。詳細には、熱変色性インキの筆跡を摩擦しその際に生じる摩擦熱で前記熱変色性インキの筆跡を熱変色可能な摩擦体を具備してなる熱変色性筆記具に関する。 The present invention relates to a thermochromic writing instrument. More specifically, the present invention relates to a thermochromic writing instrument that is equipped with a friction body that can thermally discolor a thermochromic ink mark by rubbing the mark and generating frictional heat.

特許文献１には、軸筒の内部に熱変色性インキを収容し、軸筒の前端のペン先より熱変色性インキが吐出可能に構成し、軸筒の後端に、熱変色性インキの筆跡を摩擦し、その際に生じる摩擦熱で熱変色性インキの筆跡を熱変色可能な摩擦体を具備してなる熱変色性筆記具が開示されている。 Patent Document 1 discloses a thermochromic writing instrument that contains thermochromic ink inside a barrel, is configured so that the thermochromic ink can be ejected from a pen tip at the front end of the barrel, and is equipped at the rear end of the barrel with a friction body that can rub the handwriting of the thermochromic ink and thermally discolor the thermochromic ink with the frictional heat generated during the friction.

特許文献１に記載の第１実施形態の構成は、軸筒と、軸筒の後端に螺合により着脱自在に装着される頭冠と、頭冠の後端に螺合により着脱自在に装着される摩擦体と、軸筒内部及び頭冠内部に収容される予備摩擦体と、を備え、軸筒は後方に突出する第１の頭冠装着部が設けられ、第１の頭冠装着部外面には第１の雄ねじ部を有し、頭冠は前方に開口する軸筒装着孔が設けられ、軸筒装着孔内面には第１の雄ねじ部に螺合可能な第１の雌ねじ部を有し、頭冠は後方に開口する摩擦体装着孔が設けられ、摩擦体装着孔内面には第２の雌ねじ部を有し、摩擦体及び予備摩擦体は前方に突出する第２の頭冠装着部が設けられ、第２の頭冠装着部外面には第２の雄ねじ部を有し、第２の頭冠装着部は摩擦体装着孔に螺合により装着可能であり、摩擦体は予備摩擦体と交換可能であることを特徴としたものである。 The configuration of the first embodiment described in Patent Document 1 includes a barrel, a cap that is detachably attached to the rear end of the barrel by screwing, a friction body that is detachably attached to the rear end of the cap by screwing, and a spare friction body that is housed inside the barrel and the cap, and the barrel is provided with a first cap attachment part that protrudes rearward, the outer surface of the first cap attachment part has a first male thread part, the cap is provided with a barrel attachment hole that opens forward, the inner surface of the barrel attachment hole has a first female thread part that can be screwed into the first male thread part, the cap is provided with a friction body attachment hole that opens rearward, the inner surface of the friction body attachment hole has a second female thread part, the friction body and the spare friction body are provided with a second cap attachment part that protrudes forward, the outer surface of the second cap attachment part has a second male thread part, the second cap attachment part can be attached to the friction body attachment hole by screwing, and the friction body is replaceable with the spare friction body.

当該第１実施形態に記載の熱変色性筆記具によれば、摩擦の際に摩擦体がぐらつくことがなく安定した適切な摩擦ができると共に、頭冠に装着された摩擦体を、容易に予備摩擦体に交換することができるため、熱変色性筆記具における摩擦性能を長期間維持することができ、商品価値の高い熱変色性筆記具を提供することができる。 The thermochromic writing instrument described in the first embodiment provides stable and appropriate friction without the friction body wobbling during friction, and the friction body attached to the crown can be easily replaced with a spare friction body, so that the friction performance of the thermochromic writing instrument can be maintained for a long period of time, making it possible to provide a thermochromic writing instrument with high commercial value.

また、特許文献１に記載の第２実施形態の構成は、軸筒と、軸筒の後端に螺合により着脱自在に装着される頭冠と、摩擦体と、を備え、軸筒は後方に突出する第１の頭冠装着部が設けられ、第１の頭冠装着部外面には第１の雄ねじ部を有し、頭冠は前方に開口する軸筒装着孔が設けられ、軸筒装着孔内面には第１の雄ねじ部に螺合可能な第１の雌ねじ部を有し、頭冠は後端に径方向内方に突出する縮径部が設けられ、摩擦体は両端に摩擦部及び予備摩擦部が設けられ、摩擦体は軸方向中央部に径方向外方に突出する鍔部が設けられ、鍔部は第１の頭冠装着部の後端部と縮径部により挟持され、摩擦体は頭冠により抜け止めされ、摩擦部と予備摩擦部は前後反転して装着可能であることを特徴としたものである。 The second embodiment described in Patent Document 1 is configured to include a barrel, a cap that is detachably attached to the rear end of the barrel by screwing, and a friction body, the barrel is provided with a first cap attachment portion that protrudes rearward, the outer surface of the first cap attachment portion has a first male thread portion, the cap is provided with a barrel attachment hole that opens forward, the inner surface of the barrel attachment hole has a first female thread portion that can be screwed into the first male thread portion, the cap is provided with a reduced diameter portion that protrudes radially inward at the rear end, the friction body is provided with a friction portion and a spare friction portion at both ends, the friction body is provided with a flange portion that protrudes radially outward at the axial center, the flange portion is clamped by the rear end of the first cap attachment portion and the reduced diameter portion, the friction body is prevented from coming off by the barrel, and the friction portion and the spare friction portion can be attached in a reversed front-to-back manner.

当該第２実施形態に記載の熱変色性筆記具によれば、摩擦の際に摩擦体がぐらつくことがなく安定した適切な摩擦ができると共に、頭冠に装着された摩擦体を、摩擦部から容易に予備摩擦部に入れ替えることができるため、熱変色性筆記具における摩擦性能を長期間維持することができ、商品価値の高い熱変色性筆記具を提供することができる。 The thermochromic writing instrument described in the second embodiment provides stable and appropriate friction without the friction body wobbling during friction, and the friction body attached to the crown can be easily replaced from the friction section to the spare friction section, so that the friction performance of the thermochromic writing instrument can be maintained for a long period of time, making it possible to provide a thermochromic writing instrument with high commercial value.

特開２０２０－６９７４３号公報JP 2020-69743 A

特許文献１に記載の第１実施形態に開事された技術では、摩擦体の外径が軸筒や頭冠の外径に対して小さいため、螺合のための適正な締め付けトルクを加えることが困難になるおそれがあり、その結果、摩擦の際には摩擦体がぐらついたり摩擦体が緩んできたりするため、安定した適切な摩擦ができないおそれがある。 In the technology disclosed in the first embodiment described in Patent Document 1, the outer diameter of the friction body is small compared to the outer diameter of the shaft tube and the crown, which may make it difficult to apply the appropriate tightening torque for screwing. As a result, the friction body may wobble or become loose during friction, which may prevent stable and appropriate friction.

一方、特許文献１に記載の第２実施形態に開事された技術では、摩擦体の取付は、摩擦体に比べて外径が大きい頭冠を把持して螺合を行うため適正な締め付けトルクを加えることが可能である。しかし、摩擦体の前方側に突出する量（長さ）は鍔部の位置によって定まるため、摩擦体を所望の突出量で装着することができないという課題がある。 On the other hand, in the technology disclosed in the second embodiment described in Patent Document 1, the friction body is attached by gripping the crown, which has a larger outer diameter than the friction body, and screwing it in, so it is possible to apply an appropriate tightening torque. However, since the amount (length) that the friction body protrudes forward is determined by the position of the flange, there is a problem in that the friction body cannot be attached with the desired protruding amount.

本発明は、以上のような知見に鑑みてなされたものであり、摩擦の際に摩擦体がぐらつくことがなく安定した適切な摩擦ができ、また、摩擦体を所望の突出量で装着することができる熱変色性筆記具を提供することである。なお、本発明において、「後」とは摩擦体装着側を指し、「前」とはその反対側を指す。 The present invention was made in consideration of the above findings, and aims to provide a thermochromic writing instrument that can provide stable and appropriate friction without the friction body wobbling during friction, and that can be attached with a desired amount of protrusion. In the present invention, "rear" refers to the side where the friction body is attached, and "front" refers to the opposite side.

本発明は、内部に熱変色性インキを収容し、前端のペン先より前記熱変色性インキが吐出可能に構成されている軸筒と、前記軸筒の後端に、前記熱変色性インキの筆跡を摩擦し、その際に生じる摩擦熱で前記熱変色性インキの筆跡を熱変色可能な摩擦体と、前記軸筒の後端に螺合により装着される頭冠と、を備え、前記軸筒の後端には、後方に突出する頭冠装着部が設けられ、前記頭冠装着部の後端には、後方に開口する摩擦体装着孔が設けられ、前記頭冠装着部の外周の少なくとも一部には、雄ねじ部と、前記頭冠と前記頭冠装着部との螺合に伴って前記頭冠の内面の一部に当接する当接部と、が形成されており、前記頭冠装着部の一部には、切欠きが形成されており、前記当接部において荷重を受ける時に前記摩擦体装着孔の内径が縮径するようになっており、前記頭冠の内面の一部には、前記雄ねじ部に螺合可能な雌ねじ部と、前記頭冠と前記頭冠装着部との螺合に伴って前記当接部が当接する案内部と、が形成されており、前記当接部は、前記頭冠と前記頭冠装着部との螺合に伴って、前記案内部から前記荷重を受けるようになっている熱変色性筆記具である。 The present invention comprises a barrel that contains thermochromic ink and is configured so that the thermochromic ink can be ejected from a pen tip at the front end, a friction body at the rear end of the barrel that rubs the handwriting of the thermochromic ink and can thermally discolor the handwriting of the thermochromic ink with the frictional heat generated at the time, and a crown that is screwed onto the rear end of the barrel, and a crown attachment part that protrudes rearward is provided at the rear end of the crown attachment part, and a friction body attachment hole that opens rearward is provided at at least a part of the outer periphery of the crown attachment part, and a male thread part is provided at the crown attachment part. a contact portion that contacts a part of the inner surface of the crown as the crown is screwed into the crown mounting part, a notch is formed in a part of the crown mounting part so that the inner diameter of the friction body mounting hole is reduced when a load is received at the contact portion, a female thread portion that can be screwed into the male thread portion and a guide portion that the contact portion contacts as the crown and the crown mounting part are screwed into each other are formed in a part of the inner surface of the crown, and the contact portion receives the load from the guide portion as the crown and the crown mounting part are screwed into each other.

本発明によれば、頭冠と頭冠装着部との螺合に伴って頭冠装着部の当接部が頭冠の案内部から荷重を受ける。この場合、頭冠装着部の切欠きの存在によって摩擦体装着孔の内径が縮径し、頭冠と頭冠装着部とが協働して摩擦体をガタつき（遊び）の無い態様で把持することができる。これにより、摩擦の際に摩擦体がぐらつくことがなく安定した適切な摩擦ができ、また、摩擦体を所望の突出量で装着することができる。 According to the present invention, as the crown and the crown mounting part are screwed together, the abutting part of the crown mounting part receives a load from the guide part of the crown. In this case, the presence of the notch in the crown mounting part reduces the inner diameter of the friction body mounting hole, and the crown and the crown mounting part cooperate to hold the friction body without rattling (play). This allows stable and appropriate friction without the friction body wobbling during friction, and also allows the friction body to be mounted with the desired protrusion amount.

また、前記当接部は前記頭冠装着部の後端に設けられることが好ましい。これによれば、当接部と切欠きの基部との距離が長くなり、摩擦体装着孔を容易に縮径させることができ、より摩擦体を確実に把持することができる。 It is also preferable that the abutment portion is provided at the rear end of the crown attachment portion. This increases the distance between the abutment portion and the base of the notch, making it easier to reduce the diameter of the friction body attachment hole and more reliably gripping the friction body.

また、前記切欠きは、前記頭冠装着部の周方向に等間隔に複数が配置されており、前記複数の切欠きの各々は、前記頭冠装着部の軸方向に延びるスリットであることが好ましい。これによれば、摩擦体装着孔の内径が周方向にバランス良く縮径することができる。 It is also preferable that the notches are arranged at equal intervals in the circumferential direction of the crown mounting part, and each of the notches is a slit extending in the axial direction of the crown mounting part. This allows the inner diameter of the friction body mounting hole to be reduced in a balanced manner in the circumferential direction.

また、前記当接部は、後端に向かって先細状であることが好ましく、前記案内部も、後端に向かって先細状であることが好ましい。前記当接部は、例えば切頭円錐面を有していることが好ましい。この場合、前記案内部は、対応する凹切頭円錐面であることが好ましい。あるいは、前記当接部は、軸線周りに回転対称な凸曲面を有していることが好ましい。この場合、前記案内部は、軸線周りに回転対称であって前記凸曲面の曲率よりも緩やかな曲率の凹曲面または凹切頭円錐面であることが好ましい。 The contact portion is preferably tapered toward the rear end, and the guide portion is also preferably tapered toward the rear end. The contact portion preferably has, for example, a truncated cone surface. In this case, the guide portion is preferably a corresponding concave truncated cone surface. Alternatively, the contact portion preferably has a convex curved surface that is rotationally symmetric about an axis. In this case, the guide portion is preferably a concave curved surface or a concave truncated cone surface that is rotationally symmetric about an axis and has a curvature that is gentler than the curvature of the convex curved surface.

また、前記摩擦体装着孔の内周面には、内向係止部が形成されており、前記摩擦体の外周面には、周状に外向係止部が形成されていることが好ましい。この場合、摩擦体装着孔が摩擦体をより確実に把持することができるため、摩擦の際に摩擦体がぐらつくことがなく安定した適切な摩擦ができる。また、内向係止部と外向係止部とを係止させる位置を変えることにより、摩擦体を所望の位置で確実に把持することができる。すなわち、摩擦体を所望の突出量で確実に装着することができる。 It is also preferable that an inward locking portion is formed on the inner peripheral surface of the friction body mounting hole, and an outward locking portion is formed circumferentially on the outer peripheral surface of the friction body. In this case, the friction body mounting hole can hold the friction body more securely, so that the friction body does not wobble during friction and stable, appropriate friction can be achieved. Furthermore, by changing the position at which the inward locking portion and the outward locking portion are locked, the friction body can be held securely in the desired position. In other words, the friction body can be securely attached with the desired protrusion amount.

また、本発明は、ペン先を備えない摩擦体が装着された摩擦具をも対象とするものである。すなわち、本発明は、軸筒と、前記軸筒の後端に、熱変色性インキの筆跡を摩擦し、その際に生じる摩擦熱で前記熱変色性インキの筆跡を熱変色可能な摩擦体と、前記軸筒の後端に螺合により装着される頭冠と、を備え、前記軸筒の後端には、後方に突出する頭冠装着部が設けられ、前記頭冠装着部の後端には、後方に開口する摩擦体装着孔が設けられ、前記頭冠装着部の外周の少なくとも一部には、雄ねじ部と、前記頭冠と前記頭冠装着部との螺合に伴って前記頭冠の内面の一部に当接する当接部と、が形成されており、前記頭冠装着部の一部には、切欠きが形成されており、前記当接部において荷重を受ける時に当該摩擦体装着孔の内径が縮径するようになっており、前記頭冠の内面の一部には、前記雄ねじ部に螺合可能な雌ねじ部と、前記頭冠と前記頭冠装着部との螺合に伴って前記当接部が当接する案内部と、が形成されており、前記当接部は、前記頭冠と前記頭冠装着部との螺合に伴って、前記案内部から前記荷重を受けるようになっている摩擦具である。 The present invention also covers a friction tool equipped with a friction body that does not have a pen tip. That is, the present invention comprises a barrel, a friction body that is attached to the rear end of the barrel and that rubs the handwriting of thermochromic ink and can thermally discolor the handwriting of the thermochromic ink with the frictional heat generated at the time, and a crown that is attached to the rear end of the barrel by screwing, and a crown attachment part that protrudes rearward is provided at the rear end of the barrel, and a friction body attachment hole that opens rearward is provided at at least a part of the outer periphery of the crown attachment part, and a male screw part that abuts against a part of the inner surface of the crown as the crown and the crown attachment part are screwed together. A notch is formed in a portion of the crown mounting portion so that the inner diameter of the friction body mounting hole is reduced when a load is received at the abutment portion, and a female thread portion that can be screwed into the male thread portion and a guide portion against which the abutment portion abuts as the crown and the crown mounting portion are screwed together are formed on a portion of the inner surface of the crown, and the abutment portion is adapted to receive the load from the guide portion as the crown and the crown mounting portion are screwed together.

本発明は、摩擦の際に摩擦体がぐらつくことがなく安定した適切な摩擦ができ、また、摩擦体を所望の突出量で装着することができる熱変色性筆記具を提供できる。 The present invention provides a thermochromic writing instrument that can provide stable and appropriate friction without the friction body wobbling during friction, and that can be attached with the desired amount of protrusion.

本発明の第１実施形態の熱変色性筆記具を示す正面図である。1 is a front view showing a thermochromic writing instrument according to a first embodiment of the present invention; 図１の軸筒の頭冠装着部を示す要部拡大斜視図である。FIG. 2 is an enlarged perspective view of a main portion showing a crown mounting portion of the barrel of FIG. 1 . 図１の摩擦体交換時の状態を示す分解図である。FIG. 2 is an exploded view showing a state in which the friction body in FIG. 1 is replaced; 図１の摩擦体装着状態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 part showing a state in which the friction body in FIG. 1 is attached. 図４の摩擦体突出量を変化させた状態を示す要部拡大縦断面図である。5 is an enlarged longitudinal sectional view of a main part showing a state in which the friction body protrusion amount in FIG. 4 is changed. FIG. 本発明の第２実施形態の摩擦体を示す斜視図である。FIG. 11 is a perspective view showing a friction body according to a second embodiment of the present invention. 本発明の第２実施形態の軸筒の頭冠装着部を示す要部拡大斜視図である。FIG. 11 is an enlarged perspective view of a main portion showing a crown mounting portion of a barrel according to a second embodiment of the present invention. 本発明の第３実施形態の軸筒の頭冠装着部を示す要部拡大斜視図である。FIG. 13 is an enlarged perspective view of a main portion showing a crown mounting portion of a barrel according to a third embodiment of the present invention.

以下、図面を参照して本発明の３つの実施の形態について説明する。 Below, three embodiments of the present invention will be described with reference to the drawings.

＜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。図１は、本発明の第１実施形態における熱変色性筆記具１の正面図であって、ペン先（筆記体）が突出していない状態を示す図である。図２は、本実施形態の軸筒３の頭冠装着部３１を示す要部拡大斜視図である。図３は、本実施形態の摩擦体４を交換する際の状態を示す分解図である。図４は、本実施形態の摩擦体装着状態を示す要部拡大縦断面図である。図５は、図４に対して摩擦体４の突出量を変化させて摩擦体４を装着した状態を示す要部拡大縦断面図である。 First Embodiment
1 to 5 show a first embodiment of the present invention. Fig. 1 is a front view of a thermochromic writing instrument 1 in the first embodiment of the present invention, showing a state in which the pen tip (writing body) does not protrude. Fig. 2 is an enlarged perspective view of a main part showing a crown mounting part 31 of a barrel 3 in this embodiment. Fig. 3 is an exploded view showing a state when replacing a friction body 4 in this embodiment. Fig. 4 is an enlarged vertical cross-sectional view of a main part showing a state in which the friction body is mounted in this embodiment. Fig. 5 is an enlarged vertical cross-sectional view of a main part showing a state in which the friction body 4 is mounted by changing the amount of protrusion of the friction body 4 from that in Fig. 4.

本実施の形態の熱変色性筆記具１は多芯式出没式筆記具であり、軸筒３側壁外面にスライド操作部を有し、該スライド操作部又はクリップ部を操作部としてスライドさせることにより筆記体の筆記先端部を軸筒３先端開口部から出没させる構成である。 The thermochromic writing instrument 1 of this embodiment is a multi-core retractable writing instrument, which has a sliding operation part on the outer surface of the side wall of the barrel 3, and is configured to make the writing tip of the writing body retract from the opening at the tip of the barrel 3 by sliding the sliding operation part or the clip part as the operation part.

筆記体は、軸筒３内に収納され、出没機構の作動によって筆記体の筆記先端部が軸筒３先端開口部から出没する筆記具を構成できる。軸筒３内に複数本（具体的には３本）の筆記体が前後方向に移動可能に収容され、各々の筆記体は、弾発体（具体的には圧縮コイルスプリング）により、後方に付勢されている。 The writing body is stored in the barrel 3, and a writing instrument can be constructed in which the writing tip of the writing body appears and disappears from the opening at the tip of the barrel 3 by operating the retraction mechanism. Multiple writing bodies (specifically, three) are stored in the barrel 3 so that they can move forward and backward, and each writing body is urged backward by a resilient body (specifically, a compression coil spring).

出没機構は、これ以外にも、軸筒後端に設けた操作部を前方に押圧することによりペン先が出没する後端ノック式、軸筒側壁外面より突出する操作部を径方向内方に押圧することによりペン先が出没するサイドノック式、軸筒後部の操作部を回転操作することによりペン先が出没する回転式等が挙げられる。 Other examples of the retractable mechanism include a rear-end knock type, in which the pen tip is retracted by pressing forward on the operating part at the rear end of the barrel, a side-knock type, in which the pen tip is retracted by pressing radially inward on the operating part that protrudes from the outer surface of the barrel side wall, and a rotation type, in which the pen tip is retracted by rotating the operating part at the rear of the barrel.

・筆記体
筆記体は、ペン先と、該ペン先が前端開口部に圧入固着されたインキ収容管と、該インキ収容管内に充填される熱変色性インキと、該熱変色性インキの後端に充填され且つ該熱変色性インキの消費に伴い前進する追従体（例えば高粘度流体）とからなる。本実施の形態の熱変色性筆記具１に適用される筆記体のうち、熱変色性インキ組成物を収容した筆記体は、軸筒３内に１本又は２本以上で収容される。 Writing body The writing body comprises a pen tip, an ink reservoir tube into whose front end opening the pen tip is press-fitted, thermochromic ink filled in the ink reservoir tube, and a follower (e.g., a high-viscosity fluid) filled in the rear end of the thermochromic ink and moving forward as the thermochromic ink is consumed. Of the writing bodies applicable to the thermochromic writing instrument 1 of this embodiment, one or more writing bodies containing a thermochromic ink composition are contained in the barrel 3.

ペン先は、例えば、前端に回転可能にボールを抱持した金属製のボールペンチップのみからなる構成、またはボールペンチップの後部外面を保持した合成樹脂製のペン先ホルダーからなる構成が挙げられる。また、インキ収容管の後端開口部に、インキ収容管と外部とが通気可能な通気孔を備えた尾栓が取り付けられる。ペン先の内部には、前端のボールを前方に押圧するスプリングが収容される。スプリングは、圧縮コイルスプリングの前端部にロッド部を備えた構成であり、ロッド部の前端がボール後面に接触している。非筆記時、スプリングの前方付勢によりボールがボールペンチップ前端の内向きの前端縁部内面に密接され、ペン先の前端からのインキの漏出及びインキの蒸発を防止できる。 The pen tip may, for example, consist of only a metal ballpoint pen tip that rotatably holds a ball at its front end, or a synthetic resin pen tip holder that holds the rear outer surface of the ballpoint pen tip. A tail plug with an air hole that allows ventilation between the ink reservoir tube and the outside is attached to the rear end opening of the ink reservoir tube. A spring that presses the ball at the front end forward is housed inside the pen tip. The spring is a compression coil spring with a rod portion at the front end, and the front end of the rod portion is in contact with the rear surface of the ball. When not writing, the forward bias of the spring brings the ball into close contact with the inner surface of the inward-facing front edge of the front end of the ballpoint pen tip, preventing ink leakage from the front end of the pen tip and ink evaporation.

・熱変色性インキ
尚、本発明において、熱変色性インキは、可逆熱変色性インキが好ましい。可逆熱変色性インキは、発色状態から加熱により消色する加熱消色型、発色状態または消色状態を互変的に特定温度域で記憶保持する色彩記憶保持型、または、消色状態から加熱により発色し、発色状態からの冷却により消色状態に復する加熱発色型等、種々のタイプを単独または併用して構成することができる。 Thermochromic ink In the present invention, the thermochromic ink is preferably a reversible thermochromic ink. The reversible thermochromic ink may be of various types, such as a thermal decolorization type that is decolorized by heating from a colored state, a color memory retention type that alternately retains a colored state or a decolorized state in a specific temperature range, or a thermal color development type that develops color from a decolorized state by heating and returns to the decolorized state by cooling from the colored state, either alone or in combination.

また、可逆熱変色性インキに含有される色材は、従来より公知の（イ）電子供与性呈色性有機化合物、（ロ）電子受容性化合物、及び（ハ）両者の呈色反応の生起温度を決める反応媒体、の必須三成分を少なくとも含む可逆熱変色性組成物をマイクロカプセル中に内包させた可逆熱変色性マイクロカプセル顔料が好適に用いられる。 The coloring material contained in the reversible thermochromic ink is preferably a reversible thermochromic microencapsulated pigment in which a reversible thermochromic composition containing at least the three essential components of (a) an electron-donating color-forming organic compound, (b) an electron-accepting compound, and (c) a reaction medium that determines the temperature at which the color-forming reaction between the two occurs is encapsulated in a microcapsule.

・軸筒
図１に示すように、本実施形態の熱変色性筆記具１は、先細状の円筒体からなる前軸３ａと、当該前軸３ａの後端部と螺合または圧入により取り付けられる円筒状の後軸３ｂと、からなる軸筒３を備えている。前軸３ａの前端には、筆記体のペン先が突出可能な開口が軸方向に貫設されている。前軸３ａ及び後軸３ｂは、合成樹脂（例えば、ポリカーボネイト等）または金属により形成される。 As shown in Fig. 1, the thermochromic writing instrument 1 of this embodiment includes a barrel 3 consisting of a tapered cylindrical front barrel 3a and a cylindrical rear barrel 3b attached to the rear end of the front barrel 3a by screwing or press-fitting. An opening is provided in the axial direction at the front end of the front barrel 3a through which the pen tip of the writing element can protrude. The front barrel 3a and the rear barrel 3b are made of synthetic resin (e.g., polycarbonate, etc.) or metal.

図１に示すように、後軸３ｂの後部の側壁には、例えば３本（２～６本から選択され得る）の前後方向に延びる細長状の窓孔３７が、径方向に貫設されている。３本の窓孔３７は、例えば、周方向に等間隔に形成されている。 As shown in FIG. 1, the rear side wall of the rear axle 3b is provided with, for example, three (select from two to six) elongated window holes 37 extending in the fore-and-aft direction and extending radially through the wall. The three window holes 37 are formed, for example, at equal intervals in the circumferential direction.

図２又は図３に示すように、軸筒３の後端部には、後方に突出する頭冠装着部３１が設けられ、頭冠装着部３１には、後述する頭冠２が螺合により着脱自在に装着される。頭冠装着部３１の後端には、後方に開口する摩擦体装着孔３４が設けられる。 As shown in Figures 2 and 3, the rear end of the barrel 3 is provided with a crown attachment part 31 that protrudes rearward, and the crown 2 described below is attached to the crown attachment part 31 in a detachable manner by screwing. The rear end of the crown attachment part 31 is provided with a friction body attachment hole 34 that opens rearward.

また、頭冠装着部３１の外周の少なくとも一部には、雄ねじ部３２と、当接部３３と、を有する。当接部３３は、頭冠２と軸筒３の頭冠装着部３１との螺合に伴って頭冠２の内面の一部（案内部２３）に当接し、頭冠２の案内部２３から荷重を受ける。 At least a portion of the outer periphery of the crown attachment portion 31 has a male thread portion 32 and an abutment portion 33. The abutment portion 33 abuts against a portion of the inner surface of the crown 2 (the guide portion 23) as the crown 2 and the crown attachment portion 31 of the barrel 3 are screwed together, and receives a load from the guide portion 23 of the crown 2.

当接部３３は頭冠装着部３１の後端に設けられることが好ましい。これによれば、当接部３３と切欠き３５の基部との距離が長くなり、摩擦体装着孔３４を容易に縮径させることができ、より摩擦体４を確実に把持することができる。 It is preferable that the abutment portion 33 is provided at the rear end of the crown attachment portion 31. This increases the distance between the abutment portion 33 and the base of the notch 35, making it easier to reduce the diameter of the friction body attachment hole 34 and more reliably gripping the friction body 4.

また、当接部３３は、後端に向かって先細状であることが好ましい。これによれば、当接部３３を案内部２３に挿入する際に頭冠内面に引っ掛かることなく挿入することが可能である。また、当接部３３は、頭冠２と軸筒３の頭冠装着部３１との螺合に伴って頭冠２の案内部２３に当接し、頭冠２の案内部２３からスムーズに荷重を受けることができ、容易に摩擦体装着孔３４の内径を縮径させることができる。 The abutment portion 33 is preferably tapered toward the rear end. This allows the abutment portion 33 to be inserted into the guide portion 23 without getting caught on the inner surface of the crown. The abutment portion 33 also abuts against the guide portion 23 of the crown 2 as the crown 2 and the crown mounting portion 31 of the barrel 3 are screwed together, allowing the abutment portion 33 to smoothly receive a load from the guide portion 23 of the crown 2, and allowing the inner diameter of the friction body mounting hole 34 to be easily reduced.

また、当接部３３は切頭円錐面を有していることがより好ましい。この場合、案内部２３は、対応する凹切頭円錐面であることが好ましい。あるいは、当接部３３は、軸線周りに回転対称な凸曲面を有していてもよい。この場合、案内部２３は、軸線周りに回転対称であって凸曲面の曲率よりも緩やかな曲率の凹曲面または凹切頭円錐面であることが好ましい。これによれば、頭冠装着部３１の当接部３３は周方向にバランスよく荷重を受けることができ、結果的に摩擦体装着孔３４の内径を周方向にバランス良く縮径することができ、摩擦体４をガタつき（遊び）の無い態様で常時把持することができる。 Moreover, it is more preferable that the abutment portion 33 has a truncated cone surface. In this case, it is preferable that the guide portion 23 has a corresponding concave truncated cone surface. Alternatively, the abutment portion 33 may have a convex curved surface that is rotationally symmetric about the axis. In this case, it is preferable that the guide portion 23 is a concave curved surface or a concave truncated cone surface that is rotationally symmetric about the axis and has a curvature that is gentler than the curvature of the convex curved surface. In this way, the abutment portion 33 of the crown mounting portion 31 can receive a load in a circumferentially balanced manner, and as a result, the inner diameter of the friction body mounting hole 34 can be reduced in a circumferentially balanced manner, and the friction body 4 can be constantly gripped without rattling (play).

頭冠装着部３１の一部には、切欠き３５が形成される。これにより、頭冠２と軸筒３の頭冠装着部３１との螺合に伴って当接部３３において荷重を受ける時に、摩擦体装着孔３４の内径が縮径する。切欠き３５は、頭冠装着部３１の周方向に等間隔に複数が配置されており、複数の切欠き３５の各々は、頭冠装着部３１の軸方向に延びるスリットであることが好ましい。これによれば、摩擦体装着孔３４の内径が周方向にバランス良く縮径することができる。 A notch 35 is formed in a part of the crown mounting part 31. As a result, when a load is received at the abutment part 33 due to the screwing of the crown 2 and the crown mounting part 31 of the barrel 3, the inner diameter of the friction body mounting hole 34 is reduced. A plurality of notches 35 are arranged at equal intervals in the circumferential direction of the crown mounting part 31, and each of the plurality of notches 35 is preferably a slit extending in the axial direction of the crown mounting part 31. This allows the inner diameter of the friction body mounting hole 34 to be reduced in a balanced manner in the circumferential direction.

また、該スリットは後端に開口し、径方向に貫通していることが好ましい。これによれば、当接部３３が受けた荷重でスリットを容易に撓ませる（径方向に縮径させる）ことができる。 It is also preferable that the slit opens at the rear end and penetrates in the radial direction. This allows the slit to be easily deflected (reduced in diameter in the radial direction) by the load received by the abutment portion 33.

本実施形態においては、雄ねじ部３２とスリットが形成されている位置は軸方向に重複していない。これにより、雄ねじ部３２が径方向に変形しないため螺合を確実に行うことができる。また、スリットが形成された当接部３３の肉厚が厚くなることがないため、当接部３３が受けた荷重でスリットを容易に撓ませる（径方向に縮径させる）ことができる。 In this embodiment, the male threaded portion 32 and the position where the slit is formed do not overlap in the axial direction. This prevents the male threaded portion 32 from deforming in the radial direction, so that screwing can be performed reliably. In addition, the thickness of the abutment portion 33 where the slit is formed does not increase, so the slit can be easily deflected (reduced in diameter in the radial direction) by the load received by the abutment portion 33.

一方、雄ねじ部３２とスリットが形成されている位置が軸方向に重複していても構わない。これにより、軸方向の部品長さ（頭冠２及び頭冠装着部３１の軸方向長さ）を短くできるため筆記具形状の自由度を上げることができる。また、スリットの軸方向の長さを長くすることができるため、当接部３３が受けた荷重でスリットを容易に撓ませる（径方向に縮径させる）ことができる。 On the other hand, the male threaded portion 32 and the position where the slit is formed may overlap in the axial direction. This allows the axial length of the parts (the axial length of the crown 2 and the crown mounting portion 31) to be shortened, thereby increasing the degree of freedom in the shape of the writing instrument. In addition, since the axial length of the slit can be lengthened, the slit can be easily deflected (reduced in diameter in the radial direction) by the load received by the abutment portion 33.

摩擦体装着孔３４の内面には、後述する摩擦体４の被把持部４１を把持する把持部を備える。本実施形態においては、把持部は円筒内面形状である。頭冠２と軸筒３の頭冠装着部３１との螺合に伴って当接部３３が案内部２３から荷重を受けた際に、把持部の内径が縮径し、後述する摩擦体４の被把持部４１を把持し、摩擦体４が装着状態となる。 The inner surface of the friction body mounting hole 34 is provided with a gripping portion that grips the gripped portion 41 of the friction body 4 described later. In this embodiment, the gripping portion has a cylindrical inner surface shape. When the abutment portion 33 receives a load from the guide portion 23 as the crown 2 and the crown mounting portion 31 of the barrel 3 are screwed together, the inner diameter of the gripping portion contracts and grips the gripped portion 41 of the friction body 4 described later, and the friction body 4 is in an attached state.

・頭冠
図３乃至図５に示すように、本実施形態の熱変色性筆記具１の軸筒３の後端には頭冠２が螺合により着脱自在に設けられる。頭冠２は、前方に開口する軸筒装着孔２１と、後方に開口する挿通部２４と、を備える。 3 to 5, the thermochromic writing instrument 1 of this embodiment has a cap 2 detachably attached by screwing to the rear end of the barrel 3. The cap 2 has a barrel mounting hole 21 that opens to the front and an insertion portion 24 that opens to the rear.

軸筒装着孔２１内面の一部には、雄ねじ部３２に螺合可能な雌ねじ部２２と、頭冠２と頭冠装着部３１との螺合に伴って当接部３３が当接する案内部２３と、を有する。案内部２３は、軸筒装着孔２１の後方、すなわち挿通部２４の前方に設けられることが好ましい。 A part of the inner surface of the shaft tube mounting hole 21 has a female threaded portion 22 that can be screwed into the male threaded portion 32, and a guide portion 23 against which the abutment portion 33 abuts as the crown 2 and the crown mounting portion 31 are screwed together. The guide portion 23 is preferably provided behind the shaft tube mounting hole 21, i.e., in front of the insertion portion 24.

また、案内部２３は、後端に向かって先細状であることが好ましい。これによれば、前述の通り、当接部３３を案内部２３に挿入する際に頭冠内面に引っ掛かることなく挿入することが可能である。また、当接部３３は、頭冠２と軸筒３の頭冠装着部３１との螺合に伴って頭冠２の案内部２３に当接し、頭冠２の案内部２３からスムーズに荷重を受けることができ、容易に摩擦体装着孔３４の内径を縮径させることができる。 In addition, it is preferable that the guide portion 23 is tapered toward the rear end. As described above, this allows the abutment portion 33 to be inserted into the guide portion 23 without getting caught on the inner surface of the crown. In addition, the abutment portion 33 abuts against the guide portion 23 of the crown 2 as the crown 2 and the crown mounting portion 31 of the barrel 3 are screwed together, allowing the abutment portion 33 to smoothly receive the load from the guide portion 23 of the crown 2, and the inner diameter of the friction body mounting hole 34 to be easily reduced.

また、案内部２３は凹切頭円錐面を有していることがより好ましい。この場合、当接部３３は、対応する凸切頭円錐面または軸線周りに回転対称な凸曲面であることが好ましい。あるいは、案内部２３は、軸線周りに回転対称な凹曲面を有していることが好ましい。この場合、当接部３３は、軸線周りに回転対称であって凹曲面の曲率よりも小さな曲率の凸曲面であることが好ましい。これによれば、頭冠装着部３１の当接部３３は周方向にバランスよく荷重を受けることができ、結果的に摩擦体装着孔３４の内径を周方向にバランス良く縮径することができ、摩擦体４をガタつき（遊び）の無い態様で常時把持することができる。 Moreover, it is more preferable that the guide portion 23 has a concave truncated cone surface. In this case, it is preferable that the abutment portion 33 is a corresponding convex truncated cone surface or a convex curved surface that is rotationally symmetric about the axis. Alternatively, it is preferable that the guide portion 23 has a concave curved surface that is rotationally symmetric about the axis. In this case, it is preferable that the abutment portion 33 is a convex curved surface that is rotationally symmetric about the axis and has a curvature smaller than that of the concave curved surface. In this way, the abutment portion 33 of the crown mounting portion 31 can receive a load in a circumferentially balanced manner, and as a result, the inner diameter of the friction body mounting hole 34 can be reduced in a circumferentially balanced manner, and the friction body 4 can be constantly gripped without rattling (play).

頭冠２の外面には、二面幅部やローレット部よりなる回転操作部を形成してもよい。該回転操作部を回転操作することにより、軸筒３と頭冠２との螺合やその解除を容易に行うことができ、軸筒３と頭冠２との容易な着脱が可能になる。回転操作部とは、例えば、スパナ掛け可能な６角形や８角形等の二面幅部、又はローレット部、その他外向突起等を挙げることができる。 A rotating operation part consisting of a two-sided width part or a knurled part may be formed on the outer surface of the crown 2. By rotating the rotating operation part, the shaft tube 3 and the crown 2 can be easily screwed together or released, making it possible to easily attach and detach the shaft tube 3 and the crown 2. Examples of the rotating operation part include a two-sided width part such as a hexagon or octagon that can be hung with a wrench, a knurled part, or other outward protrusions.

・摩擦体
熱変色性筆記具１は摩擦体４を備える。本実施の形態において、摩擦体４は内部に熱変色性インキを内蔵し且つ該熱変色性インキを筆記体より吐出可能な筆記具の後端に設ける構成が好ましい。 Friction Body The thermochromic writing instrument 1 includes a friction body 4. In this embodiment, the friction body 4 preferably has thermochromic ink built therein and is provided at the rear end of the writing instrument from which the thermochromic ink can be ejected.

本実施の形態において、摩擦体４を構成する弾性材料は、弾性を有する合成樹脂（ゴム、エラストマー）が好ましく、例えば、シリコーン樹脂、ＳＢＳ樹脂（スチレン－ブタジエン－スチレン共重合体）、ＳＥＢＳ樹脂（スチレン－エチレン－ブチレン－スチレン共重合体）、フッ素系樹脂、クロロプレン樹脂、ニトリル樹脂、ポリエステル系樹脂、エチレンプロピレンジエンゴム（ＥＰＤＭ）又は２種以上のゴム弾性材料の混合物、及び、ゴム弾性材料と合成樹脂との混合物等が挙げられる。摩擦体４を構成する弾性を有する合成樹脂は、高摩耗性の弾性材料（例えば、消しゴム等）ではなく、摩擦時に摩耗カス（消しカス）が殆ど生じない低摩耗性の弾性材料である。摩擦体４は筆記具と別体の任意形状の部材である摩擦具とを組み合わせて筆記具セットを得ることもできるが、筆記具に摩擦体４を設けることにより、携帯性に優れたものとなる。 In this embodiment, the elastic material constituting the friction body 4 is preferably a synthetic resin (rubber, elastomer) having elasticity, such as silicone resin, SBS resin (styrene-butadiene-styrene copolymer), SEBS resin (styrene-ethylene-butylene-styrene copolymer), fluorine-based resin, chloroprene resin, nitrile resin, polyester-based resin, ethylene propylene diene rubber (EPDM), a mixture of two or more rubber elastic materials, and a mixture of a rubber elastic material and a synthetic resin. The synthetic resin having elasticity constituting the friction body 4 is not a highly abrasive elastic material (e.g., eraser, etc.), but a low-abrasive elastic material that generates almost no abrasion debris (eraser debris) during friction. The friction body 4 can be combined with a writing instrument and a friction tool that is a separate member of any shape to obtain a writing instrument set, but providing the friction body 4 to the writing instrument makes it highly portable.

摩擦体４は、ポリプロピレン樹脂及びスチレン系熱可塑性エラストマーの混合物、またはポリプロピレン樹脂及びポリプロピレン系熱可塑性エラストマーの混合物から形成されてもよい。混合物の配合比率がそれぞれ重量比で１：１～１：４であり、研磨剤、可塑剤、充填剤を含有せず、ＪＩＳＫ６２５１に規定されたデュロメータ硬度Ａが７０°～１００°となる材質からなり、ＪＩＳＳ６０５０－２００２に規定する鉛筆描線の消し能力（消字率）が７０％以下のものである可塑剤を含有しない低摩耗性の弾性材料から形成される。それによって摩擦体４は、擦過時に消しカスが生じにくく、熱変色性も優れているので有効である。 The friction body 4 may be formed from a mixture of polypropylene resin and a styrene-based thermoplastic elastomer, or a mixture of polypropylene resin and a polypropylene-based thermoplastic elastomer. The blending ratio of the mixture is 1:1 to 1:4 by weight, and the material does not contain abrasives, plasticizers, or fillers, and has a durometer hardness A of 70° to 100° as specified in JIS K6251. The friction body 4 is formed from a low-wear elastic material that does not contain plasticizers and has a pencil line erasing ability (erasing rate) of 70% or less as specified in JIS S 6050-2002. As a result, the friction body 4 is effective because it is less likely to produce eraser shavings when rubbed and has excellent thermal discoloration resistance.

摩擦体４は、摩擦時に摩耗カス（消しカス）が殆ど生じない低摩耗性の弾性材料から形成されるが、摩擦する面の種類若しくは状態又は摩擦の方法によっては、少しずつ摩耗又は破損する可能性がある。摩耗又は破損した摩擦体４では適切な摩擦ができず、熱変色性インキの筆跡を摩擦し、その際に生じる摩擦熱で熱変色性インキの筆跡を熱変色させることが困難となるおそれがある。 The friction body 4 is made of a low-wear elastic material that produces almost no wear debris (eraser debris) when rubbed, but depending on the type or condition of the rubbing surface or the method of rubbing, it may gradually wear down or become damaged. A worn or damaged friction body 4 cannot provide appropriate friction, and it may become difficult to rub the thermochromic ink marks and thermally discolor the thermochromic ink marks with the frictional heat generated during the process.

また、摩擦体４は、摩擦する面に鉛筆等で筆記された筆跡があった場合又は摩擦する面が汚れていた場合は、鉛筆等の芯のカス又は汚れが摩擦体４に転写され、摩擦体４が汚損する可能性がある。汚損した摩擦体４では、別の紙面等を摩擦した際に摩擦体４に付着した汚れ等を紙面に転写してしまい、紙面を汚してしまうおそれがある。 In addition, if there is handwriting written with a pencil or the like on the friction surface, or if the friction surface is dirty, pencil lead residue or dirt may be transferred to the friction body 4, causing the friction body 4 to become dirty. If the friction body 4 is dirty, the dirt or the like that has adhered to the friction body 4 may be transferred to the paper surface when the friction body 4 is rubbed against another paper surface, causing the paper surface to become dirty.

摩擦体４が摩耗若しくは破損又は汚損等した場合に、摩耗若しくは破損又は汚損等した摩擦体４を新しい摩擦体に交換することで再度適切な摩擦をすることが可能となる。 If the friction body 4 becomes worn, damaged, or soiled, it is possible to provide appropriate friction again by replacing the worn, damaged, or soiled friction body 4 with a new friction body.

以下、図３乃至図５を参照して、本実施形態の摩擦体４について説明する。摩擦体４は軸方向中央部に円柱状の被把持部４１を備える。また、摩擦体４は両端に、被把持部４１に隣接する第１摩擦部４ａ及び第２摩擦部４ｂを備える。 The friction body 4 of this embodiment will be described below with reference to Figs. 3 to 5. The friction body 4 has a cylindrical gripped portion 41 in the axial center. The friction body 4 also has a first friction portion 4a and a second friction portion 4b at both ends, adjacent to the gripped portion 41.

図３に示すように、被把持部４１上には、段部又は鍔部を有さないことが好ましい。言い換えれば、摩擦体装着孔に挿入する際に引っ掛かりとならない形状であればよい。これにより、把持部４１上であれば摩擦体４を把持する位置を任意に定めることができる。すなわち、摩擦体４を所望の出長さで装着することができる。 As shown in FIG. 3, it is preferable that the gripped portion 41 does not have a step or a flange. In other words, it is sufficient if the gripped portion 41 has a shape that does not get caught when inserted into the friction body mounting hole. This allows the position for gripping the friction body 4 to be determined arbitrarily on the gripped portion 41. In other words, the friction body 4 can be mounted with the desired extension length.

また、第１摩擦部４ａと第２摩擦部４ｂは前後対称形状であるが好ましい。これにより、第１摩擦部４ａと第２摩擦部４ｂは前後反転して装着可能であり、摩擦時に摩擦部４ａにより隠れて見えなくなる筆跡部が狭くなり、筆跡視認性が向上し、より消去を行いやすくなる。 It is also preferable that the first friction part 4a and the second friction part 4b have a symmetrical shape from front to back. This allows the first friction part 4a and the second friction part 4b to be attached by being reversed from front to back, narrowing the handwriting part that is hidden by the friction part 4a when rubbed, improving the visibility of the handwriting and making it easier to erase.

摩擦体４の交換の前後で同一の摩擦性能を得る場合は、摩擦部４ａと予備摩擦部４ｂは同一形状であることが好ましい。これにより、第１摩擦部４ａが摩耗等して第２摩擦部４ｂに交換した後でも交換前と同じ一定の摩擦性能を得ることができ、安定した摩擦性能が維持できる。 If the same friction performance is to be obtained before and after replacement of the friction body 4, it is preferable that the friction part 4a and the spare friction part 4b have the same shape. This makes it possible to obtain the same constant friction performance as before replacement even after the first friction part 4a has worn down and is replaced with the second friction part 4b, thereby maintaining stable friction performance.

また、摩擦範囲を摩擦部形状により変える場合は、第１摩擦部４ａと第２摩擦部４ｂは異なる形状であることが好ましい。これにより、一つの摩擦体で、広い範囲と狭い範囲を共に摩擦することができる。 When changing the friction range by changing the shape of the friction part, it is preferable that the first friction part 4a and the second friction part 4b have different shapes. This allows one friction body to provide friction in both a wide range and a narrow range.

摩擦体４は、軸心方向に空気流路を備えてもよい。これにより、摩擦体４を幼児が誤って飲み込んだ場合でも、摩擦体４の空気流路が通気可能となり気道を確保することができ、窒息事故を回避できる。 The friction body 4 may have an air flow path in the axial direction. This allows air to flow through the air flow path of the friction body 4, ensuring an airway even if an infant accidentally swallows the friction body 4, and thus preventing choking accidents.

本実施の形態の熱変色筆記具１は、第１摩擦部４ａ及び第２摩擦部４ｂの外面には、二面幅部やローレット部よりなる回転操作部が形成されてもよい。回転操作部を把持して摩擦体４を操作することにより、摩擦体４の頭冠２からの出長さの調整をより容易に行うことができる。回転操作部とは、例えば、スパナ掛け可能な６角形や８角形等の二面幅部、又はローレット部等を挙げることができる。 The thermochromic writing instrument 1 of this embodiment may have a rotation operation part formed of a two-sided width part or a knurled part on the outer surface of the first friction part 4a and the second friction part 4b. By gripping the rotation operation part and operating the friction body 4, it is easier to adjust the length of the friction body 4 extending from the crown 2. Examples of the rotation operation part include a two-sided width part such as a hexagon or octagon that can be hung with a wrench, or a knurled part.

以上のような構成の熱変色性筆記具１は、以下のように作用する。 The thermochromic writing instrument 1 configured as above functions as follows.

摩擦体装着前は、熱変色性筆記具１の後部は、図３に示すような分解状態である。図３に示す状態においては、摩擦体装着孔３４の内径は、摩擦体４の被把持部４１の外径と同じか又は僅かに大きい状態である。そのため、摩擦体４は摩擦体装着孔３４内に遊嵌又は遊挿可能である。 Before the friction body is attached, the rear part of the thermochromic writing instrument 1 is in a disassembled state as shown in FIG. 3. In the state shown in FIG. 3, the inner diameter of the friction body attachment hole 34 is the same as or slightly larger than the outer diameter of the gripped portion 41 of the friction body 4. Therefore, the friction body 4 can be loosely fitted or inserted into the friction body attachment hole 34.

その後、頭冠２内に設けられた雌ねじ部２２と頭冠装着部３１に設けられた雄ねじ部３２との螺合によって頭冠２を装着していくと、頭冠２内に設けられた案内部２３と頭冠装着部３１に設けられた当接部３３が当接し、当接部３３において荷重を受ける。 Then, when the crown 2 is attached by screwing the female threaded portion 22 provided in the crown 2 into the male threaded portion 32 provided in the crown attachment portion 31, the guide portion 23 provided in the crown 2 comes into contact with the abutment portion 33 provided in the crown attachment portion 31, and the abutment portion 33 bears the load.

該荷重が、頭冠装着部３１に設けられた切欠き３５に作用して摩擦体装着孔３４の内径を縮径させる。これにより、摩擦体装着孔３４の内径は、摩擦体４の被把持部４１の外径より小さくなるため、図４に示すように摩擦体４は摩擦体装着孔３４内にガタつき（遊び）の無い態様で把持することができる。 The load acts on the notch 35 provided in the crown mounting portion 31, reducing the inner diameter of the friction body mounting hole 34. As a result, the inner diameter of the friction body mounting hole 34 becomes smaller than the outer diameter of the gripped portion 41 of the friction body 4, so that the friction body 4 can be gripped in the friction body mounting hole 34 without any rattling (play) as shown in FIG. 4.

一方、摩擦体４を取り外す又は摩擦体４の頭冠２からの出長さを変更する場合は、図４に示す状態から頭冠２の螺合を緩めていく。この場合、当接部３３が案内面から受けていた荷重が小さくなり、摩擦体装着孔３４の内径は、再び摩擦体４の被把持部４１の外径と同じか又は僅かに大きい状態となる。そのため、摩擦体４は摩擦体装着孔３４内に遊嵌又は遊挿状態となり、摩擦体４を軸方向に移動させ、図４に比べて出長さが長い図５に示す状態にすることができる。または、摩擦体４を取外し可能な着脱自在の状態とすることができる。なお、本発明の摩擦体の取付構造は、シャープペン等に搭載される消しゴムや、消しゴムのみを搭載した消し具においての、消しゴムの取付構造としても適用できる。 On the other hand, when removing the friction body 4 or changing the length of the friction body 4 protruding from the crown 2, the screwing of the crown 2 is loosened from the state shown in FIG. 4. In this case, the load that the abutting portion 33 received from the guide surface is reduced, and the inner diameter of the friction body mounting hole 34 is again the same as or slightly larger than the outer diameter of the gripped portion 41 of the friction body 4. Therefore, the friction body 4 is loosely fitted or loosely inserted in the friction body mounting hole 34, and the friction body 4 can be moved axially to the state shown in FIG. 5, which has a longer protruding length compared to FIG. 4. Alternatively, the friction body 4 can be made detachable and detachable. The friction body mounting structure of the present invention can also be applied as an eraser mounting structure for an eraser mounted on a mechanical pencil or the like, or for an eraser equipped with only an eraser.

以上の通り、本実施形態の熱変色性筆記具１によれば、摩擦の際に摩擦体４がぐらつくことがなく安定した適切な摩擦ができ、また、摩擦体４を所望の突出量で装着することができる熱変色性筆記具１を提供できる。 As described above, the thermochromic writing instrument 1 of this embodiment can provide a thermochromic writing instrument 1 that can provide stable and appropriate friction without the friction body 4 wobbling during friction, and can also be attached with the desired amount of protrusion.

＜第２実施形態＞
図６又は図７に、本発明の第２実施形態を示す。これは、第１実施形態の変形例であり、第１実施形態と異なる点は、摩擦体装着孔３４の内周面には、内向係止部３６が形成されており、摩擦体４の外周面には、周状に外向係止部４２が形成されている点である。他の構成及び作用効果は第１実施形態と同じであるため、その説明は省略する。 Second Embodiment
6 and 7 show a second embodiment of the present invention. This is a modification of the first embodiment, and differs from the first embodiment in that an inward locking portion 36 is formed on the inner peripheral surface of the friction body mounting hole 34, and an outward locking portion 42 is formed circumferentially on the outer peripheral surface of the friction body 4. The other configurations and effects are the same as those of the first embodiment, so the description thereof will be omitted.

本発明の第２実施形態において、摩擦体装着孔３４の内周面には、内向係止部３６が形成されている。該内向係止部３６は、図７に示すように摩擦体装着孔３４の内周面に離散的に配置された複数の内向突起である。内向係止部３６は、頭冠装着部３１に複数が配置されている切欠き３５（スリット）間に等間隔に配置されることが好ましい。 In the second embodiment of the present invention, an inward locking portion 36 is formed on the inner peripheral surface of the friction body mounting hole 34. The inward locking portion 36 is a plurality of inward protrusions discretely arranged on the inner peripheral surface of the friction body mounting hole 34 as shown in FIG. 7. It is preferable that the inward locking portions 36 are arranged at equal intervals between the notches 35 (slits) of which a plurality are arranged in the crown mounting portion 31.

また、本発明の第２実施形態において、摩擦体４の外周面、すなわち被把持部４１上には、図６に示すように周状の外向係止部４２が形成されている。該外向係止部４２は、環状の外向突起であり、軸方向に等間隔に連続して８本形成されている。該外向係止部４２は、少なくとも２本形成されていることが好ましい。 In the second embodiment of the present invention, as shown in FIG. 6, a circumferential outward locking portion 42 is formed on the outer circumferential surface of the friction body 4, i.e., on the gripped portion 41. The outward locking portion 42 is an annular outward protrusion, and eight of them are formed in succession at equal intervals in the axial direction. It is preferable that at least two outward locking portions 42 are formed.

これらにより、摩擦体装着孔３４が摩擦体４をより確実に把持することができるため、摩擦の際に摩擦体４がぐらつくことがなくより安定した適切な摩擦ができる。また、内向係止部３６と外向係止部４２とを係止させる位置を変えることにより、摩擦体４を所望の位置で確実に把持することができる。言い換えれば、摩擦体装着後は摩擦体４が軸方向にずれることを防ぎ、容易に所望の突出量を維持することができる。 As a result, the friction body mounting hole 34 can hold the friction body 4 more securely, so that the friction body 4 does not wobble during friction, and more stable and appropriate friction can be achieved. Also, by changing the position at which the inward locking portion 36 and the outward locking portion 42 are locked, the friction body 4 can be securely held at the desired position. In other words, after the friction body is attached, the friction body 4 is prevented from shifting in the axial direction, and the desired protrusion amount can be easily maintained.

また、本実施形態においては、外向係止部４２が、軸方向に等間隔に連続して８本形成されている。これにより、摩擦体４を取り外した際も、再度同じ位置で摩擦体４を装着することが容易であり、言い換えれば容易に所望の位置で摩擦体４を把持することができる。 In addition, in this embodiment, eight outward locking portions 42 are formed in a row at equal intervals in the axial direction. This makes it easy to reattach the friction body 4 in the same position even after removing it, or in other words, to easily hold the friction body 4 in the desired position.

＜第３実施形態＞
図８に、本発明の第３実施形態を示す。これは、第２実施形態の変形例であり、第２実施形態と異なる点は、摩擦体装着孔３４の内周面には、周状の内向係止部３６が形成されている点である。他の構成及び作用効果は第１及び第２実施形態と同じであるため、その説明は省略する。 Third Embodiment
8 shows a third embodiment of the present invention. This is a modification of the second embodiment, and differs from the second embodiment in that a circumferential inward locking portion 36 is formed on the inner peripheral surface of the friction body mounting hole 34. Other configurations and effects are the same as those of the first and second embodiments, so a description thereof will be omitted.

本発明の第３実施形態において、摩擦体装着孔３４の内周面には、周状の内向係止部３６が２本形成されている。該内向係止部３６は、図８に示すように摩擦体装着孔３４の内周面のスリット部を除いた部分に、周状に連続的に配置された内向突起である。該内向突起は、少なくとも１本形成されていればよいが、図８に示すように、軸方向に等間隔に連続して複数形成されていることがより好ましい。 In the third embodiment of the present invention, two circumferential inward locking portions 36 are formed on the inner circumferential surface of the friction body mounting hole 34. The inward locking portions 36 are inward protrusions that are continuously arranged circumferentially on the inner circumferential surface of the friction body mounting hole 34 excluding the slit portion, as shown in FIG. 8. It is sufficient that at least one inward protrusion is formed, but it is more preferable that multiple inward protrusions are formed continuously at equal intervals in the axial direction, as shown in FIG. 8.

また、本実施形態の軸筒の内向係止部が軸方向に等間隔に連続して複数形成されている場合、軸筒の内向係止部３６の１本ごとの距離（軸方向の配置ピッチ）と、図６に示す摩擦体４の外向係止部４２の１本ごとの距離（軸方向の配置ピッチ）とが等しいことが好ましい。 In addition, when the inward locking portions of the barrel of this embodiment are formed in a plurality of consecutive positions at equal intervals in the axial direction, it is preferable that the distance between each of the inward locking portions 36 of the barrel (axial arrangement pitch) is equal to the distance between each of the outward locking portions 42 of the friction body 4 shown in FIG. 6 (axial arrangement pitch).

これらにより、摩擦体装着孔３４が摩擦体４をより高い把持力で把持することができるため、摩擦の際に摩擦体４がぐらつくことがなく、より安定した適切な摩擦ができる。また、摩擦体装着後は摩擦体４が軸方向にずれることをより防ぎ、容易に所望の突出量を維持することができる。 As a result, the friction body mounting hole 34 can grip the friction body 4 with a stronger gripping force, so the friction body 4 does not wobble during friction, and more stable and appropriate friction can be achieved. In addition, after the friction body is mounted, the friction body 4 is more prevented from shifting in the axial direction, making it easy to maintain the desired amount of protrusion.

また、本発明は、ペン先を備えない摩擦体が装着された摩擦具をも対象とするものである。作用効果は第１乃至第３実施形態と同じであるため、その説明は省略する。すなわち、本発明は、軸筒と、前記軸筒の後端に、熱変色性インキの筆跡を摩擦し、その際に生じる摩擦熱で前記熱変色性インキの筆跡を熱変色可能な摩擦体と、前記軸筒の後端に螺合により装着される頭冠と、を備え、前記軸筒の後端には、後方に突出する頭冠装着部が設けられ、前記頭冠装着部の後端には、後方に開口する摩擦体装着孔が設けられ、前記頭冠装着部の外周の少なくとも一部には、雄ねじ部と、前記頭冠と前記頭冠装着部との螺合に伴って前記頭冠の内面の一部に当接する当接部と、が形成されており、前記頭冠装着部の一部には、切欠きが形成されており、前記当接部において荷重を受ける時に当該摩擦体装着孔の内径が縮径するようになっており、前記頭冠の内面の一部には、前記雄ねじ部に螺合可能な雌ねじ部と、前記頭冠と前記頭冠装着部との螺合に伴って前記当接部が当接する案内部と、が形成されており、前記当接部は、前記頭冠と前記頭冠装着部との螺合に伴って、前記案内部から前記荷重を受けるようになっている摩擦具である。 The present invention also covers a friction tool equipped with a friction body that does not have a pen tip. The effects are the same as those of the first to third embodiments, so a description thereof will be omitted. That is, the present invention comprises a barrel, a friction body at the rear end of the barrel that rubs the handwriting of thermochromic ink and can thermally discolor the handwriting of the thermochromic ink with the frictional heat generated at that time, and a crown that is screwed and attached to the rear end of the barrel, and a crown attachment part that protrudes rearward is provided at the rear end of the crown attachment part, and a friction body attachment hole that opens rearward is provided at at least a part of the outer periphery of the crown attachment part, and a male screw part that abuts against a part of the inner surface of the crown as the crown and the crown attachment part are screwed together. A notch is formed in a portion of the crown mounting portion so that the inner diameter of the friction body mounting hole is reduced when a load is received at the abutment portion, and a female thread portion that can be screwed into the male thread portion and a guide portion against which the abutment portion abuts as the crown and the crown mounting portion are screwed together are formed on a portion of the inner surface of the crown, and the abutment portion is adapted to receive the load from the guide portion as the crown and the crown mounting portion are screwed together.

１熱変色性筆記具
２頭冠
２１軸筒装着孔
２２雌ねじ部
２３案内部
２４挿通部
３軸筒
３ａ前軸
３ｂ後軸
３１頭冠装着部
３２雄ねじ部
３３当接部
３４摩擦体装着孔
３５切欠き
３６内向係止部
３７窓孔
４摩擦体
４ａ第１摩擦部
４ｂ第２摩擦部
４１被把持部
４２外向係止部 1 Thermochromic writing instrument 2 Crown 21 Barrel mounting hole 22 Female threaded portion 23 Guide portion 24 Insertion portion 3 Barrel 3a Front shaft 3b Rear shaft 31 Crown mounting portion 32 Male threaded portion 33 Contact portion 34 Friction body mounting hole 35 Cut Notch 36 Inward locking part 37 Window hole 4 Friction body 4a First friction part 4b Second friction part 41 Grasped part 42 Outward locking part

Claims

A barrel that contains thermochromic ink inside and is configured so that the thermochromic ink can be ejected from a pen tip at a front end thereof;
a friction body disposed at the rear end of the barrel, capable of rubbing the mark of the thermochromic ink and thermally discoloring the mark of the thermochromic ink with frictional heat generated at the time;
a crown attached to the rear end of the barrel by screwing;
A crown mounting portion protruding rearward is provided at the rear end of the barrel,
A friction body mounting hole opening rearward is provided at the rear end of the crown mounting portion,
At least a part of the outer periphery of the crown mounting part is formed with a male thread part and an abutment part that abuts against a part of the inner surface of the crown as the crown and the crown mounting part are screwed together,
A notch is formed in a part of the crown mounting portion, and an inner diameter of the friction body mounting hole is reduced when a load is received at the abutment portion,
A female threaded portion that can be screwed into the male threaded portion and a guide portion against which the abutment portion abuts as the crown and the crown mounting portion are screwed together are formed on a part of the inner surface of the crown,
The abutment portion is adapted to receive the load from the guide portion as the crown and the crown mounting portion are screwed together ,
The contact portion is tapered toward the rear end, and the guide portion is also tapered toward the rear end,
The abutment portion has a truncated conical surface .

2. The thermochromic writing implement according to claim 1, wherein the abutment portion is provided at a rear end of the crown mounting portion.

The notches are arranged at equal intervals in a circumferential direction of the crown mounting portion,
3. The thermochromic writing instrument according to claim 1, wherein each of the plurality of cutouts is a slit extending in an axial direction of the crown mounting portion.

An inward locking portion is formed on the inner circumferential surface of the friction body mounting hole,
4. The thermochromic writing implement according to claim 1, wherein an outward engaging portion is formed on an outer circumferential surface of the friction body.

A shaft cylinder,
a friction body disposed at the rear end of the barrel, capable of rubbing the thermochromic ink mark and thermally discoloring the thermochromic ink mark with the frictional heat generated at the time;
a crown attached to the rear end of the barrel by screwing;
A crown mounting portion protruding rearward is provided at the rear end of the barrel,
A friction body mounting hole opening rearward is provided at the rear end of the crown mounting portion,
At least a part of the outer periphery of the crown mounting part is formed with a male thread part and an abutment part that abuts against a part of the inner surface of the crown as the crown and the crown mounting part are screwed together,
A notch is formed in a part of the crown mounting portion, and an inner diameter of the friction body mounting hole is reduced when a load is applied to the abutment portion,
a female thread portion that can be screwed into the male thread portion, and a guide portion with which the abutment portion abuts as the crown and the crown mounting portion are screwed together,
The abutment portion is adapted to receive the load from the guide portion as the crown and the crown mounting portion are screwed together ,
The contact portion is tapered toward the rear end, and the guide portion is also tapered toward the rear end,
The abutment portion is a friction tool having a truncated cone surface .