PRESSURE REGULATING DEVICE FOR HYDRAULIC CLUTCH

PURPOSE:To provide a hydraulic clutch for marine use which can be engaged lightly in a short time without causing a shock, by retaining a high hydraulic pressure until the clutch is engaged after switched either in a forward or reverse driving mode, and lowering the pressure just immediately before it is engaged. CONSTITUTION:A low pressure port 12 of automatic two-stage pressure regulating valve 5 is directly communicated from a circuit 16 to a switch valve 2, and the port 12 is closed by means of the switch valve 2 while a clutch is in a neutral position, thereby retaining the valve 5 at a high pressure through a high pressure port 13. Then, when the switch valve 2 is switched either in a forward or reverse driving mode, the port 12 which is closed by the switch valve 2 instantly caused to open to a lubrication oil passage 14 or a drain passage 27 communicating with respective lubricating portions 25 of respective bearing and the like in an engine E via an oil cooling device 24 while having its pressure regulated through a lubrication oil pressure regulating valve 26. In consequence, the hydraulic pressure can be maintained at a low level while the engine E runs at a low r.p.m., and at a preset level while the engine E runs at a high r.p.m. as regulated depending on the then r.p.m. In this manner, the steering capability and boarding comfortableness can be improved.