JP4097537B2

JP4097537B2 - Propeller shaft

Info

Publication number: JP4097537B2
Application number: JP2003022779A
Authority: JP
Inventors: 寛一江田; 豊奥出
Original assignee: Showa Corp
Current assignee: Showa Corp
Priority date: 2003-01-30
Filing date: 2003-01-30
Publication date: 2008-06-11
Anticipated expiration: 2023-01-30
Also published as: JP2004232761A

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プロペラシャフトであって、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。
(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】
(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ドスペースを遊嵌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]
BACKGROUND OF THE INVENTION
The present invention relates to a propeller shaft of a vehicle.
[0002]
[Prior art]
There exists a thing of patent document 1 as a propeller shaft which absorbs the impact load by the collision of a vehicle.
[0003]
The propeller shaft of Patent Document 1 has two first and second adjacent shock absorbers juxtaposed in the axial direction. Adjacent shock absorbing portions are provided at both ends of a common outer shaft, one shock absorbing portion connecting one inner shaft to the outer shaft, and the other connecting the other inner shaft to the outer shaft. The shock absorbing part. The shock load acting on the vehicle is a process in which the first shock absorbing portion first contracts one inner shaft with respect to the outer shaft and causes one inner shaft to enter the hollow portion of the outer shaft by the first shock absorbing stroke. To be absorbed. If the first shock absorbing part cannot absorb the impact load, the second shock absorbing part then contracts the outer shaft with respect to the other inner shaft, and the outer shaft is moved to the other inner side by the second shock absorbing stroke. In the process of penetrating around the shaft, the shock load is further absorbed and relaxed.
[0004]
[Patent Document 1]
JP 11-303846 ([0022], FIG. 2)
[0005]
[Problems to be solved by the invention]
In the propeller shaft of Patent Document 1, when both the first and second adjacent shock absorbing parts absorb and reduce the shock load, both the inner shafts are successively placed in the outer shaft, and the first and second shock absorbing members are successively absorbed. Enter each stroke. Since both the inner shafts are installed on the same shaft, in order to avoid mutual interference, the outer shaft needs to have a margin longer than the total length of the first and second shock absorbing strokes. The overall length of the is increased, and the weight also becomes excessive.
[0006]
An object of the present invention is to ensure a constant shock absorbing stroke without increasing the overall length of a propeller shaft formed by arranging a plurality of shock absorbing portions in the axial direction.
[0007]
[Means for Solving the Problems]
According to a first aspect of the present invention, in the propeller shaft having an impact absorbing portion that connects the outer shaft and the inner shaft that are spline-fitted to each other so as to be contracted by an impact load, the plurality of the impact absorbing portions are juxtaposed in the axial direction. When the outer shaft and the inner shaft of at least one shock absorbing portion are contracted between adjacent shock absorbing portions, the outer shaft or inner shaft of one shock absorbing portion is the outer shaft of the other shock absorbing portion. or loosely scheduled portion which allows fitting Yu the inner shaft, a propeller shaft provided on the outer shaft or the inner shaft of the shock absorbing portion of the advance said other, the phase Tonariru shock absorbing portion of the common outer shaft When one impact absorbing portion is provided at each of both ends and one inner shaft is connected to the outer shaft and the other shock absorbing portion is connected to the outer shaft, the other inner shaft is connected to the outer shaft. The hollow part can be loosely fitted to one inner shaft. In which it was to be a fitting portion to be.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
1 is a plan view showing a propeller shaft, FIG. 2 is an enlarged view showing a main part of FIG. 1 in a partially broken view, FIG. 3 is a cross-sectional view showing a first shock absorber, and FIG. 4 is a diagram showing the second shock absorber. It is sectional drawing shown.
[0010]
As shown in FIG. 1, the propeller shaft 10 of an automobile includes two shaft members divided into a front shaft 11 and a rear shaft 12, and the shafts 11 and 12 are connected by a universal joint 13. A front end portion of the front shaft 11 is coupled to a coupling yoke 15 connected to an output shaft of the engine side transmission via a universal joint 14. A rear end portion of the rear shaft 12 is connected via a universal joint 16 to a connecting yoke 17 connected to a differential gear. A second inner shaft 22 (to be described later) of the front shaft 11 is supported by the center bracket 19 via a center bearing 18 and a 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 the 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 the first inner shaft 21 and the second inner shaft 22 to both ends of the hollow outer shaft 20, and the outer shaft 20 and the first inner shaft 21 can be contracted by an impact load. The first shock absorber 30 that is connected in this manner, and the second shock absorber 40 that is connected so that the outer shaft 20 and the second inner shaft 22 can be contracted by an impact load are provided as follows.
[0012]
As shown in FIG. 2, the outer shaft 20 has a first sleeve 20B welded to one end of the steel pipe 20A and a second sleeve 20C welded to the other end of the steel pipe 20A, and the first sleeve 20B and the second sleeve 20C. Spline teeth 20D and 20E extending in the axial direction are formed on the inner peripheral surface of the inner surface. The first inner shaft 21 has one end 21A as a mounting portion of the universal joint 14, the other end 21B as a hollow shaft portion, and spline teeth 21C extending in the axial direction on the outer peripheral surface of the other end 21B. The spline teeth 21C are lightly press-fitted into the spline teeth 20D of the first sleeve 20B and engaged with the splines. The second inner shaft 22 has one end 22A as an inner shaft mounting portion of a universal joint (constant velocity joint) 13, and has spline teeth 22C extending in the axial direction on the outer peripheral surface of the other end 22B. The spline teeth 22C are lightly press-fitted into the spline teeth 20E of the second sleeve 20C and are engaged with the splines.
[0013]
(First shock absorber 30) (FIG. 3)
The first shock absorbing portion 30 press-fits the outer periphery of the support member 31 formed of an annular collar into a press-fit inner diameter portion 20F provided on the first sleeve 20B at one end of the outer shaft 20, and the end surface of the first inner shaft 21 as the outer shaft. 20 in the contraction direction (the direction in which the first inner shaft 21 enters and absorbs the hollow portion of the outer shaft 20, the rightward direction in FIG. 3).
[0014]
The first sleeve 20B at one end of the outer shaft 20 has a spline tooth 20D smaller than the press-fitted inner diameter part 20F for the support member 31, and an annular stepped part 20G is provided between the press-fitted inner diameter part 20F and the spline tooth 20D. Then, the retaining ring 32 engaged with the annular groove 21D provided near the outer end side with respect to the spline teeth 21C of the other end 21B of the first inner shaft 21 is engaged with the step portion 20G. At this time, the support member 31 presses against the end surface 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. To do. As a result, the outer shaft 20 and the first inner shaft 21 are assembled together in an axial direction, and the protruding 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 absorber 30 is as follows.
(1) Lightly press-fit 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. 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 protrudes 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 axially moved 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 protrusion 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-fitting 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 engaged with the stepped 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-fit inner diameter portion 20H provided on the second sleeve 20C at the other end of the outer shaft 20, and the end surface of the second inner shaft 22 on the outer side. It is made to contact | abut to the end surface of the supporting member 41 with the shrinkage | contraction direction with respect to the axis | shaft 20 (the direction in which the 2nd inner side axis | shaft 22 enters into the hollow part of the outer side axis | shaft 20, and shrinks).
[0019]
The second sleeve 20C at the other end of the outer shaft 20 has a spline tooth 20E smaller than the press-fitted inner diameter part 20H for the support member 41, and an annular stepped part 20I is provided between the press-fitted inner diameter part 20H and the spline tooth 20E. Then, the retaining ring 42 engaged with the annular groove 22D provided near the outer end side with respect to the spline teeth 22C of the other end 22B of the second inner shaft 22 is engaged with the step portion 20I. At this time, the support member 41 presses against the end surface of the second inner shaft 22 in the extending direction 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 step portion 20I. To do. As a result, the outer shaft 20 and the second inner shaft 22 are assembled together in an axial direction, and the protruding 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) Lightly press-fit 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. 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 protrudes 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 axially moved until the retaining ring 42 engaged with the second inner shaft 22 abuts and engages with the stepped portion 20I of the second sleeve 20C of the outer shaft 20. Slide (extend). Thereby, the protrusion 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-fitting 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 engaged with the stepped portion 20I 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 from the front of the vehicle deforms a crushable zone such as an engine room of the vehicle body and then acts on the engine, the impact load extends from the transmission to the front shaft 11 of the propeller shaft 10 and the first shaft 11 of the front shaft 11. Absorption is alleviated in order by the shock absorber 30 and the second shock absorber 40.
[0024]
That is, in the first shock absorber 30, the impact load removes the spline fitting between the spline teeth 20 </ b> D of the first sleeve 20 </ b> B of the outer shaft 20 and the spline teeth 21 </ b> C of the other end 21 </ b> B of the first inner shaft 21. The support member 31 press-fitted into the press-fitting inner diameter portion 20F of the first sleeve 20B of the outer shaft 20 is removed, the other end 21B of the first inner shaft 21 is caused to enter the steel pipe 20A of the outer shaft 20, and the outer shaft 20 And the first inner shaft 21 are relatively contracted. The impact load is efficiently absorbed and relaxed by the energy for removing the support member 31 from the press-fitted inner diameter portion 20F of the first sleeve 20B and its relative displacement. The movement of the first inner shaft 21 stops when the stopper portion (flange) 21E (FIG. 1) on the one end 21A side of the first inner shaft 21 comes into contact with the end surface of the first sleeve 20B of the outer shaft 20, This movement length of the inner shaft 21 becomes the shock absorption stroke S1 of the first shock absorber 30.
[0025]
When the first impact absorbing portion 30 cannot absorb the impact load, the stopper portion 21E on the one end 21A side of the first inner shaft 21 comes into contact with the end surface of the first sleeve 20B of the outer shaft 20, thereby causing the impact load. Extends to the side of the second shock absorber 40 via the outer shaft 20, and the second shock absorber 40 further absorbs the shock load in the same manner as the first shock absorber 30. That is, the impact load removes the spline fitting 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 removed, the other end 22B of the second inner shaft 22 is inserted into 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 and the second sleeve 20C of the outer shaft 20 move through the rubber-like elastic member 18A of the center bracket 19 and move. The impact load is efficiently absorbed and relaxed by the energy for removing the support member 41 from the press-fitted inner diameter portion 20H of the second sleeve 20C and its relative displacement. The movement of the outer shaft 20 stops when the end surface of the second sleeve 20C of the outer shaft 20 abuts against the stopper portion 22E (FIG. 1) on the one end 22A side of the second inner shaft 22, and this movement length of the outer shaft 20 is increased. Becomes the shock absorption stroke S2 of the second shock absorber 40.
[0026]
However, in the propeller shaft 10, when the outer shaft 20 of the second shock absorber 40 and the second inner shaft 22 contract between the adjacent shock absorbers 30 and 40, The first inner shaft 21 is provided in advance with a free fitting scheduled portion 33 that can be loosely fitted so that the second inner shaft 22 overlaps the first inner shaft 21 of the first shock absorber 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 the loosely fitted portion 33. 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 impact absorbing portions 30 and 40, the press-fit strength of the support members 31 and 41 with respect to the impact load is set to a level that does not generate a reference impact that is a fatal impact on the cabin occupant when the impact load is input.
[0028]
According to this embodiment, there exist the following effects.
(1) In the propeller shaft 10, when both the first and second adjacent shock absorbers 30 and 40 absorb and relax the shock load, both the inner shafts 21 and 22 are placed inside the outer shaft 20. The first and second shock absorbing strokes S1 and S2 enter one after another. Although both the inner shafts 21 and 22 are installed on the same shaft, the hollow portion of the first inner shaft 21 constitutes a loosely-fitted scheduled portion 33 that allows the second inner shaft 22 to be loosely fitted. upon absorption relaxation of impact load due to the absorption section 40, the second inner shaft 22 loosely fitted without any interference loosely scheduled portion 33 of the first inner shaft 21. Therefore, it is not necessary for the outer shaft 20 to have a surplus length that is equal to or greater than the total length of the first and second shock absorbing strokes S1 and S2, so that it is not necessary to increase the overall length of the propeller shaft 10, and Weight can be reduced.
[0029]
(2) The loose fitting scheduled 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 loose fitting length .
[0030]
Although the embodiment of the present invention has been described with reference to the drawings, the specific configuration of the present invention is not limited to this embodiment, and there are design changes and the like without departing from the scope of the present invention. Are also included in the present invention. For example, in the present embodiment, the impact absorbing portion is formed by press-fitting the support member into the inner diameter of the outer shaft and abutting the end surface of the inner shaft on the support member in the contraction direction with respect to the outer shaft. The absorbing portion may be a member that press-fits the support member into the inner diameter of the outer shaft in any manner, or may have another configuration that does not use the press-fit support member.
[0031]
【The invention's effect】
According to the present invention, a predetermined shock absorbing stroke length can be easily ensured without increasing the overall length in a propeller shaft formed by arranging a plurality of shock absorbing portions in the axial direction.
[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.
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]
DESCRIPTION OF SYMBOLS 10 Propeller shaft 20 Outer axis | shaft 21, 22 Inner axis | shaft 30,40 Shock absorption part 33 Free fitting scheduled part

Claims

In a propeller shaft having an impact absorbing portion that connects an outer shaft and an inner shaft that are spline-fitted to each other so as to be contracted by an impact load,
A plurality of the shock absorbing parts are juxtaposed in the axial direction,
Between Aitonaru shock absorbing portion, when the outer shaft and inner shaft shrinkage of at least one of the shock absorbing portion, the outer shaft or the inner shaft of the outer shaft or the inner shaft of one of the shock-absorbing portion and the other of the shock-absorbing portion the loosely scheduled portion which allows fitting Yu, a propeller shaft provided on the outer shaft or the inner shaft of the shock absorbing portion of the advance said other,
The adjacent shock absorbing portions are provided at both ends of a common outer shaft, one shock absorbing portion connecting one inner shaft to the outer shaft, and the other connecting the other inner shaft to the outer shaft. When consisting of shock absorbing parts
A propeller shaft having a hollow portion of the other inner shaft as a free fitting planned portion that allows loose fitting of the one inner shaft.