JP2004232761A

JP2004232761A - Propeller shaft

Info

Publication number: JP2004232761A
Application number: JP2003022779A
Authority: JP
Inventors: Kanichi Eda; 寛一江田; Yutaka Okude; 豊奥出
Original assignee: Showa Corp
Current assignee: Showa Corp
Priority date: 2003-01-30
Filing date: 2003-01-30
Publication date: 2004-08-19
Anticipated expiration: 2023-01-30
Also published as: JP4097537B2

Abstract

PROBLEM TO BE SOLVED: To provide a propeller shaft of such a structure that a plurality of shock absorption parts are arranged in the axial direction, capable of securing a constant shock absorbing stroke without causing the overall length to become too large. SOLUTION: The propeller shaft is equipped with an outer shaft 20 and inner shafts 21 and 22 which are put in spline fitting with each other and has shock absorption parts 30 and 40 to couple them together in such a way as contracting with an impact load, wherein the shock absorption parts 30 and 40 are arranged parallel in the axial direction, and the inner shaft 21 of the shock absorption part 30 is furnished with a loose fit planned part 33 to enable a loose fit so that the inner shaft 22 of the shock absorption part 40 is lapped in the axial direction on the inner shaft 21 of the shock absorption part 30 when the outer shaft 20 and the inner shaft 22 of the shock absorption part 40 are contracting between adjoining shock absorption parts 30 and 40. COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は車両のプロペラシャフトに関する。
【０００２】
【従来の技術】
車両の衝突等による衝撃荷重を吸収するプロペラシャフトとして、特許文献１に記載のものがある。
【０００３】
特許文献１のプロペラシャフトは、第１と第２の２つの相隣る衝撃吸収部を軸方向に並置している。相隣る衝撃吸収部は、共通の外側軸の両端のそれぞれに設けられ、該外側軸に一方の内側軸を連結した一方の衝撃吸収部と、該外側軸に他方の内側軸を連結した他方の衝撃吸収部とからなる。そして、車両に作用する衝撃荷重は、まず第１衝撃吸収部で一方の内側軸を外側軸に対して収縮させ、一方の内側軸を第１衝撃吸収ストロークだけ外側軸の中空部に侵入させる過程で吸収緩和される。第１衝撃吸収部で衝撃荷重が吸収しきれない場合には、次に第２衝撃吸収部で外側軸を他方の内側軸に対して収縮させ、外側軸を第２衝撃吸収ストロークだけ他方の内側軸のまわりに侵入させる過程で、衝撃荷重を更に吸収緩和する。
【０００４】
【特許文献１】
特開平１１−３０３８４６（［００２２］、図２）
【０００５】
【発明が解決しようとする課題】
特許文献１のプロペラシャフトでは、第１と第２の相隣る衝撃吸収部が共に衝撃荷重を吸収緩和するとき、両方の内側軸が外側軸の内部に相次いで第１と第２の衝撃吸収ストロークずつ侵入する。両方の内側軸は同一軸上に設置されるから、互いの干渉を回避するため、外側軸は第１と第２の衝撃吸収ストロークの合計長以上の余裕長を具備する必要があり、プロペラシャフトの全長が長大になり、重量も過大になる。
【０００６】
本発明の課題は、複数の衝撃吸収部を軸方向に配置してなるプロペラシャフトにおいて、全長を長大化することなく、一定の衝撃吸収ストロークを確保することにある。
【０００７】
【課題を解決するための手段】
請求項１の発明は、相互にスプライン嵌合された外側軸と内側軸を衝撃荷重により収縮し得るように連結する衝撃吸収部を有するプロペラシャフトにおいて、複数の前記衝撃吸収部を軸方向に並置してなり、相隣る衝撃吸収部の間で、少なくとも一方の衝撃吸収部の外側軸と内側軸の収縮時に、一方の衝撃吸収部の外側軸又は内側軸が他方の衝撃吸収部の外側軸又は内側軸に軸方向で相ラップするように遊嵌可能にする遊嵌予定部を、予め該他方の衝撃吸収部の外側軸又は内側軸に設けたものである。
【０００８】
請求項２の発明は、請求項１の発明において更に、前記相隣る衝撃吸収部が共通の外側軸の両端のそれぞれに設けられ、該外側軸に一方の内側軸を連結した一方の衝撃吸収部と、該外側軸に他方の内側軸を連結した他方の衝撃吸収部からなるとき、他方の内側軸の中空部を、一方の内側軸を遊嵌可能にする遊嵌予定部とするようにしたものである。
【０００９】
【発明の実施の形態】
図１はプロペラシャフトを示す平面図、図２は図１の要部を一部破断して示す拡大図、図３は第１衝撃吸収部を示す断面図、図４は第２衝撃吸収部を示す断面図である。
【００１０】
自動車のプロペラシャフト１０は、図１に示す如く、前側シャフト１１と後側シャフト１２に分割された２本のシャフト部材からなり、両シャフト１１、１２を自在継手１３により連結して構成される。前側シャフト１１の前端部は、自在継手１４を介して、エンジン側のトランスミッションの出力軸に接続される連結ヨーク１５に連結される。後側シャフト１２の後端部には、自在継手１６を介して、デファレンシャルギヤに接続される連結ヨーク１７に連結される。尚、前側シャフト１１の後述する第２内側軸２２は、センタベアリング１８、ゴム状弾性部材１８Ａを介してセンタブラケット１９に支持される。
【００１１】
プロペラシャフト１０は、衝突等による衝撃荷重を吸収するため、第１と第２の衝撃吸収部３０、４０を前側シャフト１１の中間部の軸方向に並置して備える。即ち、前側シャフト１１は、中空外側軸２０の両端部に第１内側軸２１と第２内側軸２２のそれぞれをスプライン嵌合し、外側軸２０と第１内側軸２１を衝撃荷重により収縮し得るように連結する第１衝撃吸収部３０と、外側軸２０と第２内側軸２２を衝撃荷重により収縮し得るように連結する第２衝撃吸収部４０を以下の如くに有する。
【００１２】
尚、外側軸２０は、図２に示す如く、鋼管２０Ａの一端に第１スリーブ２０Ｂを溶接するとともに、鋼管２０Ａの他端に第２スリーブ２０Ｃを溶接し、第１スリーブ２０Ｂと第２スリーブ２０Ｃの内周面に軸方向に延びるスプライン歯２０Ｄ、２０Ｅを形成している。第１内側軸２１は、一端２１Ａを自在継手１４の取付部とし、他端２１Ｂを中抜き軸部とし、他端２１Ｂの外周面に軸方向に延びるスプライン歯２１Ｃを形成している。スプライン歯２１Ｃは第１スリーブ２０Ｂのスプライン歯２０Ｄに軽圧入されてスプライン嵌合する。第２内側軸２２は、一端２２Ａを自在継手（等速ジョイント）１３のインナー軸取付部とし、他端２２Ｂの外周面に軸方向に延びるスプライン歯２２Ｃを形成している。スプライン歯２２Ｃは第２スリーブ２０Ｃのスプライン歯２０Ｅに軽圧入されてスプライン嵌合する。
【００１３】
（第１衝撃吸収部３０）（図３）
第１衝撃吸収部３０は、外側軸２０の一端の第１スリーブ２０Ｂに設けた圧入内径部２０Ｆに、環状カラーからなる支持部材３１の外周を圧入し、第１内側軸２１の端面を外側軸２０に対する収縮方向（第１内側軸２１が外側軸２０の中空部に入って吸収する方向、図３の右向き方向）で支持部材３１の端面に当接させる。
【００１４】
外側軸２０の一端の第１スリーブ２０Ｂは、支持部材３１のための圧入内径部２０Ｆよりスプライン歯２０Ｄを小径にし、圧入内径部２０Ｆとスプライン歯２０Ｄとの間に環状段差部２０Ｇを設ける。そして、第１内側軸２１の他端２１Ｂのスプライン歯２１Ｃに対する外端側の側傍に設けた環状溝２１Ｄに係着した止め輪３２をその段差部２０Ｇに係止する。このとき、支持部材３１は、外側軸２０に対する伸長方向において第１内側軸２１の端面に押当たり、第１内側軸２１の環状溝２１Ｄに係着した止め輪３２を段差部２０Ｇに押当て保持する。これにより、外側軸２０と第１内側軸２１とは軸方向にがたなく一体組付けし、外側軸２０に対する第１内側軸２１の突出位置（組付位置）を定める。
【００１５】
第１衝撃吸収部３０の組付け手順は以下の如くなされる。
（１）外側軸２０の第１スリーブ２０Ｂに設けたスプライン歯２０Ｄと、第１内側軸２１の他端２１Ｂに設けたスプライン歯２１Ｃを軽圧入する。外側軸２０と第１内側軸２１を、第１内側軸２１の環状溝２１Ｄが外方に突出するまで軸方向にスライド（短縮）させ、環状溝２１Ｄに止め輪３２を係着する。
【００１６】
（２）外側軸２０と第１内側軸２１を、第１内側軸２１に係着した止め輪３２が外側軸２０の第１スリーブ２０Ｂの段差部２０Ｇに当接して係止するまで軸方向にスライド（伸長）させる。これにより、外側軸２０に対する第１内側軸２１の突出位置（組付位置）が定まる。
【００１７】
（３）外側軸２０の第１スリーブ２０Ｂの圧入内径部２０Ｆに支持部材３１を圧入する。この際、止め輪３２が第１スリーブ２０Ｂの段差部２０Ｇに係止する状態を確保しつつ、第１内側軸２１の端面と支持部材３１の端面を当接させる。
（４）外側軸２０の第１スリーブ２０Ｂに鋼管２０Ａの一端を溶接する。
【００１８】
（第２衝撃吸収部４０）（図４）
第２衝撃吸収部４０は、外側軸２０の他端の第２スリーブ２０Ｃに設けた圧入内径部２０Ｈに、環状カラーからなる支持部材４１の外周を圧入し、第２内側軸２２の端面を外側軸２０に対する収縮方向（第２内側軸２２が外側軸２０の中空部に入って収縮する方向、図４の左向き方向）で支持部材４１の端面に当接させる。
【００１９】
外側軸２０の他端の第２スリーブ２０Ｃは、支持部材４１のための圧入内径部２０Ｈよりスプライン歯２０Ｅを小径にし、圧入内径部２０Ｈとスプライン歯２０Ｅとの間に環状段差部２０Ｉを設ける。そして、第２内側軸２２の他端２２Ｂのスプライン歯２２Ｃに対する外端側の側傍に設けた環状溝２２Ｄに係着した止め輪４２をその段差部２０Ｉに係止する。このとき、支持部材４１は、外側軸２０に対する伸長方向において第２内側軸２２の端面に押当たり、第２内側軸２２の環状溝２２Ｄに係着した止め輪４２を段差部２０Ｉに押当て保持する。これにより、外側軸２０と第２内側軸２２とは軸方向にがたなく一体組付けし、外側軸２０に対する第２内側軸２２の突出位置（組付位置）を定める。
【００２０】
第２衝撃吸収部４０の組付け手順は以下の如くなされる。
（１）外側軸２０の第２スリーブ２０Ｃに設けたスプライン歯２０Ｅと、第２内側軸２２の他端２２Ｂに設けたスプライン歯２２Ｃを軽圧入する。外側軸２０と第２内側軸２２を、第２内側軸２２の環状溝２２Ｄが外方に突出するまで軸方向にスライド（短縮）させ、環状溝２２Ｄに止め輪４２を係着する。
【００２１】
（２）外側軸２０と第２内側軸２２を、第２内側軸２２に係着した止め輪４２が外側軸２０の第２スリーブ２０Ｃの段差部２０Ｉに当接して係止するまで軸方向にスライド（伸長）させる。これにより、外側軸２０に対する第２内側軸２２の突出位置（組付位置）が定まる。
【００２２】
（３）外側軸２０の第２スリーブ２０Ｃの圧入内径部２０Ｈに支持部材４１を圧入する。この際、止め輪４２が第２スリーブ２０Ｃの段差部２０Ｉに係止する状態を確保しつつ、第２内側軸２２の端面と支持部材４１の端面を当接させる。
（４）外側軸２０の第２スリーブ２０Ｃに鋼管２０Ａの他端を溶接する。
【００２３】
次に、プロペラシャフト１０の作動について説明する。
車両の前方から衝撃荷重が、車体のエンジンルーム等のクラッシャブルゾーンを変形させた後、エンジンに作用すると、この衝撃荷重がトランスミッションからプロペラシャフト１０の前側シャフト１１に及び、前側シャフト１１の第１衝撃吸収部３０と第２衝撃吸収部４０で順に吸収緩和される。
【００２４】
即ち、第１衝撃吸収部３０にあっては、衝撃荷重が外側軸２０の第１スリーブ２０Ｂのスプライン歯２０Ｄと第１内側軸２１の他端２１Ｂのスプライン歯２１Ｃとのスプライン嵌合を外すとともに、外側軸２０の第１スリーブ２０Ｂの圧入内径部２０Ｆに圧入してある支持部材３１を抜き外し、第１内側軸２１の他端２１Ｂを外側軸２０の鋼管２０Ａ内部に侵入させ、外側軸２０と第１内側軸２１を相対収縮させる。衝撃荷重は、支持部材３１を第１スリーブ２０Ｂの圧入内径部２０Ｆから抜き外すエネルギーとその相対変位とにより効率的に吸収緩和されることになる。第１内側軸２１の移動は、第１内側軸２１の一端２１Ａ側のストッパ部（フランジ）２１Ｅ（図１）が外側軸２０の第１スリーブ２０Ｂの端面に当接することで停止し、第１内側軸２１のこの移動長が第１衝撃吸収部３０の衝撃吸収ストロークＳ１になる。
【００２５】
第１衝撃吸収部３０で衝撃荷重が吸収しきれない場合には、第１内側軸２１の一端２１Ａ側のストッパ部２１Ｅが外側軸２０の第１スリーブ２０Ｂの端面に当接することで、衝撃荷重が外側軸２０を介して第２衝撃吸収部４０の側に及び、第２衝撃吸収部４０が第１衝撃吸収部３０と同様にして衝撃荷重を更に吸収する。即ち、衝撃荷重が外側軸２０の第２スリーブ２０Ｃのスプライン歯２０Ｅと第２内側軸２２の他端２２Ｂのスプライン歯２２Ｃとのスプライン嵌合を外すと共に、外側軸２０の第２スリーブ２０Ｃの圧入内径部２０Ｈに圧入してある支持部材４１を抜き外し、外側軸２０の鋼管２０Ａの内部に第２内側軸２２の他端２２Ｂを侵入させ、外側軸２０と第２内側軸２２を相対収縮させる。このとき、外側軸２０の鋼管２０Ａ、第２スリーブ２０Ｃはセンタブラケット１９のゴム状弾性部材１８Ａを突き破って移動する。衝撃荷重は、支持部材４１を第２スリーブ２０Ｃの圧入内径部２０Ｈから抜き外すエネルギーとその相対変位とにより効率的に吸収緩和されることになる。外側軸２０の移動は、外側軸２０の第２スリーブ２０Ｃの端面が第２内側軸２２の一端２２Ａ側のストッパ部２２Ｅ（図１）に当接することで停止し、外側軸２０のこの移動長が第２衝撃吸収部４０の衝撃吸収ストロークＳ２になる。
【００２６】
しかるに、プロペラシャフト１０にあっては、相隣る衝撃吸収部３０、４０の間で、第２衝撃吸収部４０の外側軸２０と第２内側軸２２の収縮時に、第２衝撃吸収部４０の第２内側軸２２が第１衝撃吸収部３０の第１内側軸２１に軸方向で相ラップするように遊嵌可能にする遊嵌予定部３３を、予め第１内側軸２１に設けてある。図２のＬは第１内側軸２１と第２内側軸２２のラップ長である。本実施形態では、第１内側軸２１の中空部の内径Ａを第２内側軸２２の外径Ｂより大径とし、この第１内側軸２１の中空部を遊嵌予定部３３とする。尚、支持部材３１の内径は第１内側軸２１の中空部の内径Ａ及び第２内側軸２２の外径Ｂより大径をなす。
【００２７】
衝撃吸収部３０、４０において、衝撃荷重に対する支持部材３１、４１の圧入強度は、衝撃荷重の入力時に、キャビンの乗員に対して致命的な衝撃となる基準衝撃を発生させない程度に設定する。
【００２８】
本実施形態によれば、以下の作用効果を奏する。
（請求項１に対応する作用効果）
▲１▼プロペラシャフト１０にあっては、第１と第２の相隣る衝撃吸収部３０、４０が共に衝撃荷重を吸収緩和するとき、両方の内側軸２１、２２が外側軸２０の内部に相次いで第１と第２の衝撃吸収ストロークＳ１、Ｓ２ずつ侵入する。両方の内側軸２１、２２は同一軸上に設置されるものの、第１内側軸２１の中空部が第２内側軸２２を遊嵌可能にする遊嵌予定部３３を構成するから、第２衝撃吸収部４０による衝撃荷重の吸収緩和時に、第２内側軸２２は第１内側軸２１の遊嵌予定部３３に何ら干渉することなく遊嵌して軸方向で相ラップする。従って、外側軸２０が第１と第２の衝撃吸収ストロークＳ１、Ｓ２の合計長以上の余裕長を具備する必要がないから、プロペラシャフト１０の全長を長大化する必要がなく、プロペラシャフト１０を軽量化できる。
【００２９】
（請求項２に対応する作用効果）
▲２▼第１内側軸２１の中空部により遊嵌予定部３３を簡易に形成でき、内側軸内の中空部のデットスペ−スをラップ長として有効に利用できる。
【００３０】
以上、本発明の実施の形態を図面により記述したが、本発明の具体的な構成はこの実施の形態に限られるものではなく、本発明の要旨を逸脱しない範囲の設計の変更等があっても本発明に含まれる。例えば、本実施形態では、衝撃吸収部を、外側軸の内径に支持部材を圧入し、内側軸の端面を外側軸に対する収縮方向で支持部材に当接してなるものとしたが、本発明の衝撃吸収部は、支持部材を外側軸の内径に如何なる態様で圧入するものでも良いし、圧入支持部材を用いることのない他の構成によるものでも良い。
【００３１】
【発明の効果】
本発明によれば、複数の衝撃吸収部を軸方向に配置してなるプロペラシャフトにおいて、全長を長大化することなく、所定の衝撃吸収ストローク長を容易に確保することができる。
【図面の簡単な説明】
【図１】図１はプロペラシャフトを示す平面図である。
【図２】図２は図１の要部を一部破断して示す拡大図である。
【図３】図３は第１衝撃吸収部を示す断面図である。
【図４】図４は第２衝撃吸収部を示す断面図である。
【符号の説明】
１０プロペラシャフト
２０外側軸
２１、２２内側軸
３０、４０衝撃吸収部
３３遊嵌予定部[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a propeller shaft of a vehicle.
[0002]
[Prior art]
Patent Document 1 discloses a propeller shaft that absorbs an impact load caused by a vehicle collision or the like.
[0003]
The propeller shaft of Patent Document 1 has two first and second adjacent shock absorbing portions juxtaposed in the axial direction. Adjacent shock absorbing portions are provided at both ends of a common outer shaft, one shock absorbing portion having one inner shaft connected to the outer shaft, and the other shock absorbing portion having the other inner shaft connected to the outer shaft. And a shock absorbing part. The impact load acting on the vehicle is obtained by first contracting one of the inner shafts with respect to the outer shaft at the first shock absorbing portion, and causing the one inner shaft to enter the hollow portion of the outer shaft by the first shock absorbing stroke. Absorption is alleviated. If the first shock absorbing portion cannot absorb the impact load, then the second shock absorbing portion contracts the outer shaft with respect to the other inner shaft, and moves the outer shaft by the second shock absorbing stroke to the other inner side. In the process of penetrating around the shaft, the impact load is further absorbed and reduced.
[0004]
[Patent Document 1]
JP-A-11-303846 ([0022], FIG. 2)
[0005]
[Problems to be solved by the invention]
In the propeller shaft disclosed in Patent Document 1, when both the first and second adjacent shock absorbing portions absorb and reduce the impact load, both the inner shafts are successively arranged inside the outer shaft in the first and second shock absorbing portions. Penetrate by stroke. Since both inner shafts are installed on the same shaft, the outer shaft must have a margin longer than the total length of the first and second shock absorbing strokes to avoid mutual interference, and the propeller shaft The overall length becomes large and the weight becomes too large.
[0006]
An object of the present invention is to ensure a constant shock absorbing stroke without increasing the overall length of a propeller shaft having a plurality of shock absorbing portions arranged in the axial direction.
[0007]
[Means for Solving the Problems]
According to a first aspect of the present invention, there is provided a propeller shaft having a shock absorbing portion for connecting an outer shaft and an inner shaft spline-fitted to each other so as to be contractable by an impact load, wherein a plurality of the shock absorbing portions are juxtaposed in the axial direction. When the outer shaft and the inner shaft of at least one of the shock absorbers contract between adjacent shock absorbers, the outer or inner shaft of one of the shock absorbers becomes the outer shaft of the other shock absorber. Alternatively, a play-fitting portion which can be freely fitted so as to overlap with the inner shaft in the axial direction is provided in advance on the outer shaft or the inner shaft of the other shock absorbing portion.
[0008]
According to a second aspect of the present invention, in the first aspect of the present invention, the adjacent shock absorbing portions are provided at both ends of a common outer shaft, respectively, and one of the shock absorbing portions is connected to one of the inner shafts. Part and the other shock-absorbing part in which the other inner shaft is connected to the outer shaft, so that the hollow portion of the other inner shaft is a loosely-fitted portion that allows one inner shaft to be loosely fitted. It was done.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
1 is a plan view showing a propeller shaft, FIG. 2 is an enlarged view showing a main part of FIG. 1 partially cut away, FIG. 3 is a sectional view showing a first shock absorbing part, and FIG. FIG.
[0010]
As shown in FIG. 1, a propeller shaft 10 of an automobile includes two shaft members divided into a front shaft 11 and a rear shaft 12, and the two shafts 11 and 12 are connected by a universal joint 13. The front end of the front shaft 11 is connected via a universal joint 14 to a connection yoke 15 connected to an output shaft of a transmission on the engine side. The rear end of the rear shaft 12 is connected via a universal joint 16 to a connection yoke 17 connected to a differential gear. A second inner shaft 22 of the front shaft 11, which will be described later, is supported by the center bracket 19 via the center bearing 18 and the rubber-like elastic member 18A.
[0011]
The propeller shaft 10 includes first and second shock absorbers 30 and 40 juxtaposed in the axial direction of an intermediate portion of the front shaft 11 in order to absorb an impact load due to a collision or the like. That is, the front shaft 11 can spline-fit each of the first inner shaft 21 and the second inner shaft 22 to both ends of the hollow outer shaft 20, and can contract the outer shaft 20 and the first inner shaft 21 by an impact load. And a second shock absorber 40 that connects the outer shaft 20 and the second inner shaft 22 so that they can be contracted by an impact load as follows.
[0012]
As shown in FIG. 2, the outer shaft 20 has a first sleeve 20B welded to one end of a steel pipe 20A, a second sleeve 20C welded to the other end of the steel pipe 20A, and a first sleeve 20B and a second sleeve 20C. The spline teeth 20D and 20E extending in the axial direction are formed on the inner peripheral surface of the spline. The first inner shaft 21 has one end 21A as a mounting portion for the universal joint 14, the other end 21B as a hollow shaft portion, and spline teeth 21C extending in the axial direction formed on the outer peripheral surface of the other end 21B. The spline teeth 21C are lightly pressed into the spline teeth 20D of the first sleeve 20B, and are spline-fitted. One end 22A of the second inner shaft 22 is used as an inner shaft mounting portion of the universal joint (constant velocity joint) 13, and spline teeth 22C extending in the axial direction are formed on the outer peripheral surface of the other end 22B. The spline teeth 22C are lightly pressed into the spline teeth 20E of the second sleeve 20C and are spline-fitted.
[0013]
(First Shock Absorber 30) (FIG. 3)
The first shock absorbing portion 30 press-fits the outer periphery of the support member 31 made of an annular collar into the press-fit inner diameter portion 20F provided on the first sleeve 20B at one end of the outer shaft 20, and fixes the end face of the first inner shaft 21 to the outer shaft. The support member 31 is brought into contact with the end surface of the support member 31 in a contraction direction relative to the support member 20 (a direction in which the first inner shaft 21 enters and absorbs the hollow portion of the outer shaft 20; a rightward direction in FIG. 3).
[0014]
The first sleeve 20B at one end of the outer shaft 20 has a smaller spline tooth 20D than the press-fit inner diameter portion 20F for the support member 31 and has an annular stepped portion 20G between the press-fit inner diameter portion 20F and the spline tooth 20D. Then, the retaining ring 32 engaged with the annular groove 21D provided on the outer end side of the other end 21B of the first inner shaft 21 with respect to the spline teeth 21C is locked to the step portion 20G. At this time, the support member 31 presses against the end face of the first inner shaft 21 in the extending direction with respect to the outer shaft 20, and presses and holds the retaining ring 32 engaged with the annular groove 21D of the first inner shaft 21 against the step portion 20G. I do. As a result, the outer shaft 20 and the first inner shaft 21 are integrally assembled without any play in the axial direction, and a projecting position (assembly position) of the first inner shaft 21 with respect to the outer shaft 20 is determined.
[0015]
The procedure for assembling the first shock absorbing section 30 is as follows.
(1) The spline teeth 20D provided on the first sleeve 20B of the outer shaft 20 and the spline teeth 21C provided on the other end 21B of the first inner shaft 21 are lightly pressed. The outer shaft 20 and the first inner shaft 21 are slid (shortened) in the axial direction until the annular groove 21D of the first inner shaft 21 projects outward, and the retaining ring 32 is engaged with the annular groove 21D.
[0016]
(2) The outer shaft 20 and the first inner shaft 21 are moved in the axial direction until the retaining ring 32 engaged with the first inner shaft 21 abuts on the stepped portion 20G of the first sleeve 20B of the outer shaft 20 and is locked. Slide (extend). Thereby, the projecting position (assembly position) of the first inner shaft 21 with respect to the outer shaft 20 is determined.
[0017]
(3) The support member 31 is press-fitted into the press-fit inner diameter portion 20F of the first sleeve 20B of the outer shaft 20. At this time, the end surface of the first inner shaft 21 and the end surface of the support member 31 are brought into contact with each other while ensuring that the retaining ring 32 is locked to the step portion 20G of the first sleeve 20B.
(4) One end of the steel pipe 20A is welded to the first sleeve 20B of the outer shaft 20.
[0018]
(Second Shock Absorber 40) (FIG. 4)
The second shock absorbing portion 40 press-fits the outer periphery of the support member 41 made of an annular collar into the press-fitting inner diameter portion 20H provided on the second sleeve 20C at the other end of the outer shaft 20, and moves the end face of the second inner shaft 22 outward. The support member 41 is brought into contact with the end surface of the support member 41 in a contraction direction with respect to the shaft 20 (a direction in which the second inner shaft 22 enters the hollow portion of the outer shaft 20 and contracts, that is, a leftward direction in FIG. 4).
[0019]
The second sleeve 20C at the other end of the outer shaft 20 has a smaller spline tooth 20E than the press-fit inner diameter portion 20H for the support member 41, and has an annular stepped portion 201 between the press-fit inner diameter portion 20H and the spline tooth 20E. Then, the retaining ring 42 engaged with the annular groove 22D provided on the side of the outer end side of the other end 22B of the second inner shaft 22 with respect to the spline teeth 22C is locked to the stepped portion 20I. At this time, the support member 41 presses against the end face of the second inner shaft 22 in the direction of extension with respect to the outer shaft 20, and presses and holds the retaining ring 42 engaged with the annular groove 22D of the second inner shaft 22 against the stepped portion 20I. I do. As a result, the outer shaft 20 and the second inner shaft 22 are integrally assembled without any play in the axial direction, and the projecting position (assembly position) of the second inner shaft 22 with respect to the outer shaft 20 is determined.
[0020]
The procedure for assembling the second shock absorber 40 is as follows.
(1) The spline teeth 20E provided on the second sleeve 20C of the outer shaft 20 and the spline teeth 22C provided on the other end 22B of the second inner shaft 22 are lightly pressed. The outer shaft 20 and the second inner shaft 22 are slid (shortened) in the axial direction until the annular groove 22D of the second inner shaft 22 projects outward, and the retaining ring 42 is engaged with the annular groove 22D.
[0021]
(2) The outer shaft 20 and the second inner shaft 22 are moved in the axial direction until the retaining ring 42 engaged with the second inner shaft 22 abuts on the stepped portion 201 of the second sleeve 20C of the outer shaft 20 and is locked. Slide (extend). Thereby, the projecting position (assembly position) of the second inner shaft 22 with respect to the outer shaft 20 is determined.
[0022]
(3) The support member 41 is press-fitted into the press-fit inner diameter portion 20H of the second sleeve 20C of the outer shaft 20. At this time, the end surface of the second inner shaft 22 and the end surface of the support member 41 are brought into contact with each other while ensuring that the retaining ring 42 is locked to the stepped portion 201 of the second sleeve 20C.
(4) The other end of the steel pipe 20A is welded to the second sleeve 20C of the outer shaft 20.
[0023]
Next, the operation of the propeller shaft 10 will be described.
When an impact load acts on the engine after deforming a crushable zone such as an engine room of the vehicle body from the front of the vehicle, the impact load is transmitted from the transmission to the front shaft 11 of the propeller shaft 10 and the first shaft 11 The shock absorbing portion 30 and the second shock absorbing portion 40 absorb and mitigate the absorption sequentially.
[0024]
That is, in the first shock absorbing portion 30, the shock load releases the spline engagement between the spline teeth 20D of the first sleeve 20B of the outer shaft 20 and the spline teeth 21C of the other end 21B of the first inner shaft 21. Then, the support member 31 press-fitted into the press-fit inner diameter portion 20F of the first sleeve 20B of the outer shaft 20 is pulled out, and the other end 21B of the first inner shaft 21 is made to enter the inside of the steel pipe 20A of the outer shaft 20. And the first inner shaft 21 is relatively contracted. The impact load is efficiently absorbed and alleviated by the energy for removing the support member 31 from the press-fit inner diameter portion 20F of the first sleeve 20B and the relative displacement thereof. The movement of the first inner shaft 21 is stopped by the stopper (flange) 21E (FIG. 1) on one end 21A side of the first inner shaft 21 abutting on the end surface of the first sleeve 20B of the outer shaft 20. This moving length of the inner shaft 21 becomes the shock absorbing stroke S1 of the first shock absorbing unit 30.
[0025]
If the impact load cannot be completely absorbed by the first impact absorbing portion 30, the stopper portion 21 E on the one end 21 A side of the first inner shaft 21 abuts on the end surface of the first sleeve 20 B of the outer shaft 20, and the impact load is reduced. Extends through the outer shaft 20 to the side of the second shock absorbing portion 40, and the second shock absorbing portion 40 further absorbs a shock load in the same manner as the first shock absorbing portion 30. That is, the impact load releases the spline engagement between the spline teeth 20E of the second sleeve 20C of the outer shaft 20 and the spline teeth 22C of the other end 22B of the second inner shaft 22, and press-fits the second sleeve 20C of the outer shaft 20. The support member 41 press-fitted into the inner diameter portion 20H is pulled out and removed, the other end 22B of the second inner shaft 22 enters the inside of the steel pipe 20A of the outer shaft 20, and the outer shaft 20 and the second inner shaft 22 are relatively contracted. . At this time, the steel pipe 20A of the outer shaft 20 and the second sleeve 20C penetrate the rubber-like elastic member 18A of the center bracket 19 and move. The impact load is efficiently absorbed and mitigated by the energy for removing the support member 41 from the press-fit inner diameter portion 20H of the second sleeve 20C and the relative displacement thereof. The movement of the outer shaft 20 is stopped when the end surface of the second sleeve 20C of the outer shaft 20 comes into contact with the stopper portion 22E (FIG. 1) on the one end 22A side of the second inner shaft 22, and the movement length of the outer shaft 20 is reduced. Is the shock absorbing stroke S2 of the second shock absorbing unit 40.
[0026]
However, in the propeller shaft 10, when the outer shaft 20 and the second inner shaft 22 of the second shock absorber 40 contract between the adjacent shock absorbers 30, 40, the second shock absorber 40 A play fitting portion 33 is provided on the first inner shaft 21 in advance so that the second inner shaft 22 can be loosely fitted so as to overlap with the first inner shaft 21 of the first shock absorbing portion 30 in the axial direction. L in FIG. 2 is the wrap length of the first inner shaft 21 and the second inner shaft 22. In the present embodiment, the inner diameter A of the hollow portion of the first inner shaft 21 is set to be larger than the outer diameter B of the second inner shaft 22, and the hollow portion of the first inner shaft 21 is defined as a portion 33 to be loosely fitted. The inner diameter of the support member 31 is larger than the inner diameter A of the hollow portion of the first inner shaft 21 and the outer diameter B of the second inner shaft 22.
[0027]
In the shock absorbing units 30 and 40, the press-fitting strength of the support members 31 and 41 with respect to the impact load is set to such an extent that a reference impact that is fatal to the occupant of the cabin is not generated when the impact load is input.
[0028]
According to the present embodiment, the following operation and effect can be obtained.
(Operation and Effect Corresponding to Claim 1)
{Circle around (1)} In the propeller shaft 10, when both the first and second adjacent shock absorbing portions 30 and 40 absorb and reduce the impact load, both the inner shafts 21 and 22 are inside the outer shaft 20. Successively, the first and second shock absorbing strokes S1 and S2 intrude one by one. Although the two inner shafts 21 and 22 are installed on the same shaft, the hollow portion of the first inner shaft 21 forms the play fitting portion 33 that allows the second inner shaft 22 to be loosely fitted. When the absorbing portion 40 absorbs and reduces the impact load, the second inner shaft 22 is loosely fitted to the portion 33 of the first inner shaft 21 without any interference and overlaps in the axial direction. Accordingly, since the outer shaft 20 does not need to have a margin longer than the total length of the first and second shock absorbing strokes S1 and S2, it is not necessary to increase the overall length of the propeller shaft 10, and the propeller shaft 10 Can be reduced in weight.
[0029]
(Operation and Effect Corresponding to Claim 2)
{Circle around (2)} The loose fit portion 33 can be easily formed by the hollow portion of the first inner shaft 21, and the dead space of the hollow portion in the inner shaft can be effectively used as the wrap length.
[0030]
As described above, the embodiment of the present invention has been described with reference to the drawings. However, the specific configuration of the present invention is not limited to this embodiment, and there are design changes and the like that do not depart from the gist of the present invention. Are also included in the present invention. For example, in the present embodiment, the shock absorbing portion is configured such that the support member is pressed into the inner diameter of the outer shaft and the end surface of the inner shaft abuts on the support member in the contraction direction with respect to the outer shaft. The absorbing section may press-fit the support member into the inner diameter of the outer shaft in any manner, or may adopt another configuration without using the press-fit support member.
[0031]
【The invention's effect】
According to the present invention, in a propeller shaft having a plurality of shock absorbing portions arranged in the axial direction, a predetermined shock absorbing stroke length can be easily secured without increasing the overall length.
[Brief description of the drawings]
FIG. 1 is a plan view showing a propeller shaft.
FIG. 2 is an enlarged view showing a main part of FIG. 1 with a part cut away.
FIG. 3 is a cross-sectional view showing a first shock absorber.
FIG. 4 is a cross-sectional view showing a second shock absorber.
[Explanation of symbols]
10 Propeller Shaft 20 Outer Shafts 21, 22 Inner Shafts 30, 40 Shock Absorbing Part 33 Planned Fit

Claims

相互にスプライン嵌合された外側軸と内側軸を衝撃荷重により収縮し得るように連結する衝撃吸収部を有するプロペラシャフトにおいて、
複数の前記衝撃吸収部を軸方向に並置してなり、
相隣る衝撃吸収部の間で、少なくとも一方の衝撃吸収部の外側軸と内側軸の収縮時に、一方の衝撃吸収部の外側軸又は内側軸が他方の衝撃吸収部の外側軸又は内側軸に軸方向で相ラップするように遊嵌可能にする遊嵌予定部を、予め該他方の衝撃吸収部の外側軸又は内側軸に設けたことを特徴とするプロペラシャフト。In a propeller shaft having a shock absorbing portion that connects the outer shaft and the inner shaft that are spline-fitted to each other so as to be contractable by an impact load,
A plurality of the shock absorbers are juxtaposed in the axial direction,
Between adjacent shock absorbing parts, when the outer axis and the inner axis of at least one of the shock absorbing parts contract, the outer axis or the inner axis of one of the shock absorbing parts becomes the outer axis or the inner axis of the other shock absorbing part. A propeller shaft, characterized in that a play-fitting portion for allowing a loose fit so as to overlap in the axial direction is provided in advance on the outer shaft or the inner shaft of the other shock absorbing portion.

前記相隣る衝撃吸収部が共通の外側軸の両端のそれぞれに設けられ、該外側軸に一方の内側軸を連結した一方の衝撃吸収部と、該外側軸に他方の内側軸を連結した他方の衝撃吸収部からなるとき、
他方の内側軸の中空部を、一方の内側軸を遊嵌可能にする遊嵌予定部とする請求項１に記載のプロペラシャフト。The adjacent shock absorbing portions are provided at both ends of a common outer shaft, one shock absorbing portion having one inner shaft connected to the outer shaft, and the other having the other inner shaft connected to the outer shaft. When it consists of shock absorbing parts,
The propeller shaft according to claim 1, wherein the hollow portion of the other inner shaft is a loosely-fitted portion that allows one of the inner shafts to be loosely fitted.