JPH0240137U

JPH0240137U -

Info

Publication number: JPH0240137U
Application number: JP1988119598U
Authority: JP
Priority date: 1988-09-12
Filing date: 1988-09-12
Publication date: 1990-03-19

Description

[Brief explanation of drawings]

第１図は本考案の液圧緩衝器のシール構造の特
徴的部分を示す要部断面図、第２図は本考案の液
圧緩衝器のシール構造を示す側断面図、第３図は
第２図の液圧緩衝器のシール部材を示す側断面図
、第４図ａ，ｂは第１図のリツプ面の突起の断面
形状を示す断面図、第５図ａは本考案の液圧緩衝
器のリツプ面がピストンロツドに圧接されたとき
の圧力分布の状態を示す概略側面図、第５図ｂは
従来の液圧緩衝器のリツプ面がピストンロツドに
圧接されたときの圧力分布の状態を示す概略側面
図、第６図は本考案及び従来例のそれぞれの場合
におけるリツプ面及びピストンロツド間の動フリ
クシヨンの変化状態を示すグラフ、第７図は本考
案及び従来例のそれぞれの場合においてピストン
の往復動の速度の変化に対する動フリクシヨンの
大きさの変化を示すグラフ、第８図は従来の液圧
緩衝器のシール構造を示す部分断面図、第９図は
第８図のシール構造の変形例を示す部分断面図で
ある。１１…外筒シリンダ、１２…内筒シリンダ、１
６…ピストンロツド、１８…シール部材、２３…
内周シールリツプ部、２３ａ…第１リツプ面、２
３ｂ…第２リツプ面、３０ａ〜３０ｅ…螺旋状突
起、３１ａ〜３１ｄ…環状突起。 Fig. 1 is a cross-sectional view of the main parts showing the characteristic parts of the seal structure of the hydraulic shock absorber of the present invention, Fig. 2 is a side cross-sectional view showing the seal structure of the hydraulic shock absorber of the present invention, and Fig. 3 is a cross-sectional view of the main parts of the seal structure of the hydraulic shock absorber of the present invention. 2 is a side cross-sectional view showing the sealing member of the hydraulic shock absorber, FIGS. 4 a and b are cross-sectional views showing the cross-sectional shape of the protrusion on the lip surface of FIG. 1, and FIG. 5 a is the hydraulic shock absorber of the present invention. A schematic side view showing the state of pressure distribution when the lip surface of the device is pressed against the piston rod, and FIG. 5b shows the state of pressure distribution when the lip surface of the conventional hydraulic shock absorber is pressed against the piston rod. A schematic side view, FIG. 6 is a graph showing changes in the dynamic friction between the lip surface and the piston rod in each case of the present invention and the conventional example, and FIG. 7 is a graph showing the reciprocation of the piston in each case of the present invention and the conventional example. A graph showing changes in the magnitude of dynamic friction with respect to changes in dynamic speed, Figure 8 is a partial sectional view showing the seal structure of a conventional hydraulic shock absorber, and Figure 9 shows a modification of the seal structure in Figure 8. FIG. 11...Outer cylinder, 12...Inner cylinder, 1
6... Piston rod, 18... Seal member, 23...
Inner seal lip portion, 23a...first lip surface, 2
3b...Second lip surface, 30a-30e...Spiral projection, 31a-31d...Annular projection.

Claims

[Scope of utility model registration request]

In a hydraulic shock absorber, a cylinder is filled with liquid and a piston is inserted, and a piston rod fixed to the piston and the cylinder expand or contract to absorb external shocks. The piston rod is provided with a seal member that seals the piston rod while allowing the sliding movement of the piston rod, and the sliding surface of the seal lip portion of the seal member that makes sliding contact with the piston rod is arranged in two stages in the longitudinal direction of the piston rod axis, and each is arranged inward of the cylinder. The lip is formed into a conical shape whose diameter gradually decreases toward the end, and a spiral projection is provided on the inner first lip surface from the tip of the lip, and an annular projection is provided on the second lip surface at a predetermined distance from the tip of the lip. A seal structure for a hydraulic shock absorber characterized by having multiple stages.