HYDRAULIC BOOSTER DEVICE

To provide a hydraulic booster device having a small, light and quiet structure.SOLUTION: A hydraulic booster device 1 includes: a hydraulic cylinder 4 having a changeover valve part 2 and a pressure boost part 3; a direction control part 7 having a first solenoid valve 5 and a direction switching valve 6; a pressure switch 8; and a manifold part 10 having a high pressure relief valve 9. The hydraulic booster device is configured such that: working fluid is fed from a pump P; the working fluid boosted in pressure by the hydraulic cylinder 4 is supplied to a hydraulic tool U; the high pressure relief valve 9 is operated and the pressure switch 8 is operated when the pressure of the working fluid reaches predetermined high pressure; the working fluid supplied to the hydraulic tool U is discharged to a tank T; a flow rate is restricted when the working fluid from a first flow passage 5e formed in the first solenoid valve 5 is caused to flow through a second flow passage 6e formed in the direction switching valve 6 toward a second spool 6b; and the flow rate is restricted when the working fluid from a third flow passage 5f formed in the first solenoid valve 5 is caused to flow through a fourth flow passage 6f formed in the direction switching valve 6 toward the second spool 6b.SELECTED DRAWING: Figure 1 【課題】小型軽量かつ静音構造の油圧ブースタ装置を提供する。【解決手段】油圧ブースタ装置１は、切換弁部２と増圧部３とを有する油圧シリンダ４と、第１電磁弁５と方向切換弁６とを有する方向制御部７と、圧力スイッチ８と、高圧リリーフ弁９を有するマニホールド部１０とを備え、ポンプＰからの作動油を送液し、油圧シリンダ４にて増圧した作動油を油圧工具Ｕに供給し、作動油が所定の高圧に達すると高圧リリーフ弁９が作動して圧力スイッチ８が作動し、油圧工具Ｕに供給した作動油をタンクＴに排出する構成であって、第１電磁弁５に形成された第１流路５ｅからの作動油が方向切換弁６に形成された第２流路６ｅを通って第２スプール６ｂに向かう際に流量が制限される構成であり、且つ、第１電磁弁５に形成された第３流路５ｆからの作動油が方向切換弁６に形成された第４流路６ｆを通って第２スプール６ｂに向かう際に流量が制限される構成である。【選択図】図１