JPS6197604U - - Google Patents

Description

【図面の簡単な説明】[Brief explanation of the drawing]

第１図は本考案の一実施例を示す多段シリンダ
の説明図、第２図は第１図の状態から更に伸長し
た状態の多段シリンダの説明図、第３図は従前の
多段シリンダの説明図である。 １２；内壁、１３；外壁、１１；可動シリンダ
、１５；ピストン、１４；ピストンロツド、１６
′；開口端部、１６；固定シリンダ、Ａ；３段シ
リンダ、１９；第１給排ポート、２０；固定配管
、２１；第２給排ポート、２２；可動シリンダの
縮小側圧油室、２３；油路、２５；ピストンロツ
ドの縮小側圧油室、２４；第１連通路、２８；可
動シリンダの伸長側圧油室、２７；ピストンロツ
ドの伸長側圧油室、２６；第２連通路、３０；第
１開閉弁、３３；第２開閉弁。 Fig. 1 is an explanatory diagram of a multistage cylinder showing an embodiment of the present invention, Fig. 2 is an explanatory diagram of the multistage cylinder in a state further expanded from the state shown in Fig. 1, and Fig. 3 is an explanatory diagram of the conventional multistage cylinder. It is. 12; Inner wall, 13; Outer wall, 11; Movable cylinder, 15; Piston, 14; Piston rod, 16
'; Open end, 16; Fixed cylinder, A; Three-stage cylinder, 19; First supply and discharge port, 20; Fixed piping, 21; Second supply and discharge port, 22; Reduction side pressure oil chamber of movable cylinder, 23; Oil passage, 25; Reduction side pressure oil chamber of piston rod, 24; First communication passage, 28; Extension side pressure oil chamber of movable cylinder, 27; Extension side pressure oil chamber of piston rod, 26; Second communication passage, 30; First opening/closing Valve, 33; second on-off valve.

Claims (1)

【実用新案登録請求の範囲】[Scope of utility model registration request] 内外２重壁よりなる可動シリンダ、当該可動シ
リンダの内壁内に摺動自在に嵌合されたピストン
を備えた中空のピストンロツド、その開口端部側
を前記内外２重壁間に位置せしめると共にその開
口端部外周を前記外壁の内周面に密接せしめさら
にその内面を前記内壁の外周面に密接せしめて前
記ピストンロツドと反対方向に延出する固定シリ
ンダよりなる多段シリンダにおいて、前記固定シ
リンダの外端部には第１給排ポートを設け、当該
第１給排ポートを前記固定シリンダの略中心軸上
に位置してその一端が前記可動シリンダの内壁内
に開口する固定配管に連通せしめ、前記可動シリ
ンダの外壁外側には第２給排ポートを設け、当該
第２給排ポートを前記固定シリンダと前記外壁で
囲繞された前記可動シリンダの縮小側圧油室に連
通する油路に連通せしめ、更に前記可動シリンダ
の縮小側圧油室と前記ピストンロツドの縮小側圧
油室を連通せしめる第１連通路と、前記固定シリ
ンダと前記内壁で囲繞された可動シリンダの伸長
側圧油室と前記ピストンロツドの伸長側圧油室を
連通せしめる第２連通路を設けると共に、前記第
１連通路には前記ピストンロツドの縮小側圧油室
から可動シリンダの縮小側圧油室への油の流れを
常時阻止する閉弁状態と前記可動シリンダが全伸
長したときに前記流れを許容する開弁状態に切り
換わる第１開閉弁を、前記第２連通路には前記可
動シリンダの伸長側圧油室からピストンロツドの
伸長側圧油室への流れを常時阻止する閉弁状態と
前記ピストンロツドが全縮小したときに前記流れ
を許容する開弁状態に切り換わる第２開閉弁を夫
々設けた多段シリンダ。 A movable cylinder consisting of an inner and outer double wall, a hollow piston rod having a piston slidably fitted into the inner wall of the movable cylinder, the open end side of which is located between the inner and outer double walls, and the opening thereof. In a multistage cylinder comprising a fixed cylinder whose end outer periphery is brought into close contact with the inner peripheral surface of the outer wall, and whose inner surface is brought into close contact with the outer peripheral surface of the inner wall and which extends in a direction opposite to the piston rod, the outer end of the fixed cylinder is provided with a first supply/discharge port, and the first supply/discharge port is communicated with a fixed pipe located approximately on the central axis of the fixed cylinder, one end of which opens into the inner wall of the movable cylinder. A second supply/discharge port is provided on the outside of the outer wall of the movable cylinder, and the second supply/discharge port is connected to an oil passage communicating with a contraction side pressure oil chamber of the movable cylinder surrounded by the fixed cylinder and the outer wall, and A first communication passage that connects the contraction side pressure oil chamber of the cylinder and the contraction side pressure oil chamber of the piston rod, and communicates the expansion side pressure oil chamber of the movable cylinder surrounded by the fixed cylinder and the inner wall with the expansion side pressure oil chamber of the piston rod. A second communication passage is provided to allow the piston rod to move forward, and the first communication passage has a valve in a closed state that always prevents the flow of oil from the contraction side pressure oil chamber of the piston rod to the contraction side pressure oil chamber of the movable cylinder, and a state in which the movable cylinder is fully extended. a first opening/closing valve that switches to an open state to allow the flow when the piston rod is opened; The multi-stage cylinder is provided with second on-off valves each switching to an open state allowing the flow when the piston rod is fully contracted.