【考案の詳細な説明】
（産業上の利用分野）
本考案は、例えばプラスチツク製の筆記具軸筒
に固着するネジ管等の如く、合成樹脂製の管体へ
圧入することにより接合する金属製の管体圧入接
合部材に関する。[Detailed description of the invention] (Industrial application field) The present invention is a metal tube that is joined by press-fitting into a synthetic resin tube, such as a threaded tube that is fixed to a plastic writing instrument barrel. This invention relates to a tube press-fit joining member.
（従来の技術）
合成樹脂製の管体と金属製の管体とを抜けにく
く且つ回転しないように接合する場合、従来主に
次の２方法がある。先ず金属製の管体を合成樹脂
製の管体へ圧入して固定する方法であり、次に両
者にネジ部を設けて螺着させる方法である。とこ
ろが前者には圧入部のしめ代を適宜な値に設定す
る困難性がある。即ちしめ代が過小であると容易
に抜けたり回転してしまうし、又逆にしめ代が過
大になると合成樹脂製の管体に割れが生じたり又
クリープが生じたりして同様に抜け易く回転し易
くなるからである。又、後者には、加工費が高く
つくこと、ネジ込みの自動化が困難なこと、及び
緩み防止工程が必要となること等の工程が煩瑣化
する欠点がある。(Prior Art) When joining a synthetic resin tube and a metal tube in a manner that prevents them from coming off and rotating, there are mainly the following two methods. First, a metal tube is press-fitted into a synthetic resin tube and fixed, and then a threaded portion is provided on both parts and screwed together. However, in the former case, there is a difficulty in setting the tightening margin of the press-fit portion to an appropriate value. In other words, if the tightening allowance is too small, it will easily fall out or rotate, and conversely, if the tightening allowance is too large, the synthetic resin tube will crack or creep, and it will also easily fall out and rotate. This is because it becomes easier to do so. Furthermore, the latter method has disadvantages such as high processing costs, difficulty in automating screwing, and complicated processes such as requiring a loosening prevention process.
そこで一般的には前者の圧入する方法に若干の
改良を加えた方法が採用されている。即ち、金属
製管体の圧入部の外周面に略鋸歯状の環状突条を
周設する方法である。この構造に依れば、略鋸歯
状の環状突条が合成樹脂製管体の内面に食い込ん
で掛止するため引抜力に対して大きな耐力を発揮
し、その分だけ圧入部のしめ代を小さく設定する
ことができ、合成樹脂製管体の割れの発生率の低
下や、クリープの影響の排除等を期待できるから
である。然しながら斯る構造にも次のような課題
が残存する。即ち、大きなトルクが作用する場
合、例えばネジ継手として使用する場合等に回転
止めすることが困難で、そのため圧入部に接着剤
を塗布するとか、圧入部の合成樹脂製管体の表面
にポンチを打つとかの手段を講ずる必要があつ
て、自動化が困難であつたり、又外面部材として
使用できない等の欠点がある。本考案の目的は斯
る課題を解決することである。 Therefore, a method that is slightly improved from the former press-fitting method is generally adopted. That is, this is a method in which approximately serrated annular protrusions are provided around the outer circumferential surface of the press-fitting portion of the metal tube. According to this structure, the roughly serrated annular protrusion bites into the inner surface of the synthetic resin tube and is hooked, so it exhibits a large resistance against pull-out force, and the tightening allowance of the press-fit part can be reduced accordingly. This is because it can be expected to reduce the incidence of cracks in synthetic resin tubes, eliminate the influence of creep, etc. However, such a structure still has the following problems. In other words, it is difficult to stop rotation when a large torque is applied, for example when used as a threaded joint, so it is necessary to apply adhesive to the press-fit part or punch the surface of the synthetic resin tube at the press-fit part. It is necessary to take measures such as striking, which makes automation difficult, and there are drawbacks such as the inability to use it as an external member. The purpose of the present invention is to solve this problem.
（問題点を解決するための手段）
前記目的を達成するために、合成樹脂製管体へ
の圧入部の外周面に略鋸歯状の環状突条を周設
し、当該環状突条の周縁の一部に先端縁切欠部を
設けたことを特徴とする合成樹脂製管体への金属
製管体圧入接合部材が案出されここに提示するも
のである。(Means for solving the problem) In order to achieve the above object, a substantially serrated annular protrusion is provided on the outer peripheral surface of the press-fitted part into the synthetic resin tube, and the peripheral edge of the annular protrusion is A joint member for press-fitting a metal tube into a synthetic resin tube has been devised and is presented herein, which is characterized by having a distal edge notch in a portion thereof.
（実施例）
図示した本考案の実施例について以下説明す
る。(Example) The illustrated example of the present invention will be described below.
第１図は筆記具に於ける先軸と後軸の連結部を
示したものであり、ここには２つの形状の異なる
黄銅製のネジ管１，２が使用されている。即ち第
１のネジ管１は、外面におねじ１ａを形成した螺
着管部１ｂを後端に有し、鍔部１ｃを外面略中央
に有し、先端縁が直線状となる先端縁切欠部１ｄ
を一部に有する略鋸歯状の環状突条１ｅを外面の
１箇所に周設した圧入管部１ｆを前端に有する構
造であり、又第２のネジ管２は、全体が圧入管部
２ａで、内面にめねじ２ｂを有し、又、先端縁に
先端縁切欠部２ｃ，２c′を一部に有する略鋸歯状
の２つの環状突条２ｄ，２d′を外面の軸方向の所
要間隔離れた２箇所に周設した構造を有してい
る。そしてネジ管１はその圧入管部１ｆをプラス
チツク製の先軸３の後端口から内部に圧入させ
て、その略鋸歯状の環状突条１ｅを先軸３の内面
にくい込ませて固定しており、又ネジ管２はその
圧入管部２ａ、即ち全体をプラスチツク製の後軸
４の前端口から内部に圧入させて、その２つ略鋸
歯状の環状突条２ｄ，２d′を夫々後軸４の内面に
くい込ませて固定接合している。そしてネジ管１
の螺着管部１ｂのおねじ１ａが、ネジ管２の内面
のめねじ２ｂと螺合されて先軸３と後軸４が連結
されているものである。尚、図中５は筆記体であ
る。 FIG. 1 shows a connecting portion between a front barrel and a rear barrel in a writing instrument, and two brass threaded tubes 1 and 2 of different shapes are used here. That is, the first threaded tube 1 has a threaded tube part 1b with a thread 1a formed on the outer surface at the rear end, a collar part 1c at approximately the center of the outer surface, and a distal edge notch with a straight distal edge. Part 1d
It has a structure in which the front end has a press-fit tube part 1f with a substantially serrated annular protrusion 1e surrounding a part of the outer surface, and the second threaded pipe 2 is entirely made up of a press-fit pipe part 2a. , two substantially serrated annular protrusions 2d, 2d' having a female thread 2b on the inner surface and partially having distal edge notches 2c, 2c' on the distal edge are spaced apart from each other by a required distance in the axial direction on the outer surface. It has a structure with two surrounding locations. The threaded tube 1 is fixed by press-fitting the press-fit tube part 1f into the plastic tip shaft 3 from the rear end opening, and inserting the approximately serrated annular protrusion 1e into the inner surface of the tip shaft 3. Also, the threaded pipe 2 is press-fitted with its press-fit pipe portion 2a, that is, the entirety, into the plastic rear shaft 4 from the front end opening, and the two approximately serrated annular protrusions 2d, 2d' are inserted into the rear shaft 4, respectively. It is embedded into the inner surface and fixedly joined. and threaded pipe 1
The male thread 1a of the threaded tube portion 1b is screwed together with the female thread 2b on the inner surface of the threaded tube 2, so that the front shaft 3 and the rear shaft 4 are connected. In addition, 5 in the figure is a cursive handwriting.
（作用）
前記実施例のネジ管１と先軸３の圧入構造に基
づいて作用を説明する。第２図は第１図Ａ−Ａ線
位置に於ける横断面図である。即ちネジ管１はそ
の環状突条１ｅが略鋸歯状を呈していて圧入する
方向側の壁面がテーパ状であるため比較的弱い力
で先軸３の内孔部に圧入可能である。そして圧入
後は引抜する方向側の壁面が垂直に近いので引抜
力に対して極めて抵抗が大きい。更に圧入した状
態では環状突条１ｅが先軸３内面にくい込んでい
るが、この環状突条１ｅの外周縁部の一部に第２
図に示す如き先端縁切欠部１ｄが設けられている
のでネジ管１と先軸３との回転が防止される。こ
の先端切欠部１ｄの存在は引抜力に対する抵抗を
若干弱めることになるが、その場合は先軸３に割
れやクリープが生じない程度に圧入しろを増大さ
せるとか、又はネジ管２の如く環状突条２ｄ，２
d′を複数設けて補償することができる。又、先端
縁にローレツトを設けることでも同様な効果が得
られる。(Operation) The operation will be explained based on the press-fit structure of the threaded pipe 1 and the tip shaft 3 of the above embodiment. FIG. 2 is a cross-sectional view taken along the line A--A in FIG. 1. That is, the threaded pipe 1 can be press-fitted into the inner hole of the tip shaft 3 with a relatively weak force because its annular protrusion 1e has a substantially serrated shape and the wall surface on the press-fitting direction side is tapered. After press-fitting, the wall surface on the side in the pulling direction is nearly vertical, so it has extremely high resistance to the pulling force. When the annular protrusion 1e is further press-fitted, the annular protrusion 1e is embedded into the inner surface of the tip shaft 3, but a second
Since the distal end edge notch 1d as shown in the figure is provided, rotation of the threaded tube 1 and the distal shaft 3 is prevented. The existence of this tip notch 1d slightly weakens the resistance to the pulling force, but in that case, it is necessary to increase the press-fitting margin to the extent that cracks or creep do not occur in the tip shaft 3, or to create an annular protrusion like the threaded pipe 2. Article 2d, 2
Compensation can be achieved by providing a plurality of d′. A similar effect can also be obtained by providing a knurl at the leading edge.
（考案の効果）
本考案は叙上の構成及び作用を有するものであ
り、圧入後の抜け防止及び回転防止に著効を発揮
する。然も圧入部に接着剤を塗布するとかの工程
が不要であり自動化を図れるし、又外面にポンチ
の跡等が残らないので外面部材としても使用でき
る等の効果もある。更に本考案は特に圧入部の外
周面に周設した環状突条の周縁の一部に先端縁切
欠部を設けるのみで回転止めが達成されて、合成
樹脂製管体に対しては何ら特別の回転止め構造を
設ける必要がないので、構造のシンプル化による
コスト低減がもたらされるという格別の効果を奏
する。(Effects of the invention) The present invention has the above-mentioned structure and function, and is extremely effective in preventing slippage and rotation after press-fitting. Moreover, there is no need for a process such as applying adhesive to the press-fitted part, so automation can be achieved, and since there are no punch marks left on the outer surface, it can also be used as an outer surface member. Furthermore, the present invention achieves rotation prevention by simply providing a tip edge notch on a part of the periphery of the annular protrusion provided on the outer circumferential surface of the press-fitting part, and there is no special need for a synthetic resin tube body. Since there is no need to provide a rotation stopper structure, a special effect is achieved in that cost reduction is brought about by simplifying the structure.
【図面の簡単な説明】[Brief explanation of the drawing]
図は本考案の実施例を示すもので、第１図は筆
記具先軸及び後軸に対するネジ管圧入部の縦断面
図、第２図は第１図Ａ−Ａ線横断面図である。
１……ネジ管、１ａ……おねじ、１ｂ……螺着
管部、１ｃ……鍔部、１ｄ……先端縁切欠部、１
ｅ……環状突条、１ｆ……圧入管部、２……ネジ
管、２ａ……圧入管部、２ｂ……めねじ、２ｃ，
２c′……先端縁切欠部、２ｄ，２d′……環状突
条、３……先軸、４……後軸、５……筆記体。
The drawings show an embodiment of the present invention, in which FIG. 1 is a longitudinal cross-sectional view of a threaded tube press-fit portion for the writing instrument's tip and rear shafts, and FIG. 2 is a cross-sectional view taken along the line A--A in FIG. 1. 1... Threaded pipe, 1a... Male thread, 1b... Threaded tube part, 1c... Flange part, 1d... Tip edge notch, 1
e...Annular protrusion, 1f...Press-fit tube part, 2...Threaded pipe, 2a...Press-fit pipe part, 2b...Female thread, 2c,
2c'... Tip edge notch, 2d, 2d'... Annular protrusion, 3... Front shaft, 4... Back shaft, 5... Cursive.