HYDRAULIC DRIVE DEVICE

• Main Authors: UEDA SUKENORI, SAJI TSUNESHIRO
• Format: Patent
• Language: English; Japanese
• Published: 23.08.2018
• Subjects: BLASTING; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR; FLUID-PRESSURE ACTUATORS; FLUID-PRESSURE ACTUATORS, e.g. SERVO-MOTORS; HAULING; HEATING; HOISTING; HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDEDFOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCEDIRECTLY TO THE SURFACE OF A LOAD; HYDRAULICS OR PNEUMATICS IN GENERAL; LIFTING; LIGHTING; MECHANICAL ENGINEERING; PERFORMING OPERATIONS; SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; TRANSPORTING; WEAPONS

PROBLEM TO BE SOLVED: To provide a hydraulic drive device capable of improving recovery efficiency of potential energy of a lifting article.SOLUTION: A hydraulic drive device 1 comprises: an operation valve 37 which is disposed in a hydraulic oil passage 35 connecting a suction port 10a of a hydraulic pump 10 with a lift cylinder 2 and controls a flow of a hydraulic oil in accordance with a manipulation variable of a lift operation lever 6 for moving a fork 5 downwards; a bypass flow rate control valve 38 which is disposed in a hydraulic oil passage 36 connecting the hydraulic oil passage 35 with a tank 13 and controls a flow rate of a hydraulic oil that is returned to the tank 13; an accumulator 39 which is connected to the hydraulic oil passage 35 and accumulates a pressure of the hydraulic oil from the lift cylinder 2; a flow rate control valve 40 for pressure accumulation which is disposed in the hydraulic oil passage 35 and controls a flow rate of a hydraulic oil that is supplied to the accumulator 39; and an orifice 41 that is disposed between a branch point A in the hydraulic oil passage 35 from the hydraulic oil passage 36 and the flow rate control valve 40 for pressure accumulation.SELECTED DRAWING: Figure 1 【課題】昇降物の位置エネルギーの回収効率を向上させることができる油圧駆動装置を提供する。【解決手段】油圧駆動装置１は、油圧ポンプ１０の吸込口１０ａとリフトシリンダ２とを接続する作動油流路３５に配設され、フォーク５を下降させるためのリフト操作レバー６の操作量に応じて作動油の流れを制御する操作弁３７と、作動油流路３５とタンク１３とを接続する作動油流路３６に配設され、タンク１３に戻る作動油の流量を制御するバイパス用流量制御弁３８と、作動油流路３５に接続され、リフトシリンダ２からの作動油を蓄圧するアキュムレータ３９と、作動油流路３５に配設され、アキュムレータ３９に供給される作動油の流量を制御する蓄圧用流量制御弁４０と、作動油流路３５における作動油流路３６との分岐点Ａと蓄圧用流量制御弁４０との間に配設されたオリフィス４１とを備える。【選択図】図１