Abstract: In a power tilt apparatus in which an operation state of a cylinder apparatus is switched between an extension side and a compression side in accordance with an oil feeding direction of a pump apparatus by a switching valve apparatus provided in a pipe passage connecting the cylinder apparatus and the pump apparatus, where a sintered body filter is provided in the middle of the pipe passage.

Abstract: In a power tilt apparatus in which an operation state of a cylinder apparatus is switched between an extension side and a compression side in accordance with an oil feeding direction of a pump apparatus by a switching valve apparatus provided in a pipe passage connecting the cylinder apparatus and the pump apparatus, where a sintered body filter is provided in the middle of the pipe passage.

Abstract: A tilt apparatus for a marine propulsion device structure having a piston constituting a cylinder apparatus with a shock blow valve and a return valve, the return valve attaching a valve body to a return hole provided in the piston, and a valve body holding device provided in the return hole.

Abstract: A tilt device for a marine propulsion unit is disclosed where a shock blow valve comprises a disk valve fixed to a valve seat surface of the piston, the valve seat surface being provided with a seal member surrounding a communication hole which opens at the valve seat surface, and the disk valve is tightly connected to the seal member.

Abstract: The present invention provides a tilt device for a marine propulsion unit comprising a hydraulic cylinder device filled with a hydraulic fluid, where a piston fixed to one end portion of a piston rod is provided slidably in an inner cylinder and an outer cylinder, a tank device for storing the hydraulic fluid, and a pump device for the telescopic operation of the hydraulic cylinder device by supplying and exhausting the hydraulic fluid in the tank device into the hydraulic cylinder device, wherein a valve block of the pump device is cast-molded, the inner cylinder and the outer cylinder of the hydraulic cylinder device are made of a pipe material, a cylinder fixing portion having a diameter larger than that of the outer cylinder is formed in the valve block, and the outer cylinder is fixed to the cylinder fixing portion by the diameter enlarging processing.

Abstract: A controller for a Hall effect sensor includes a sensor section including a Hall effect sensor with a hysteresis set in the output electric signal characteristic with respect to the magnetic flux density, a power supply section for supplying a source power to the Hall effect sensor, and a signal processor for processing a signal output from the sensor section. The power supply section supplies power with a voltage, which is varied cyclically in a predetermined range and is increased gradually, to the Hall effect sensor.

Abstract: A steering system for a boat propelling apparatus is disclosed, which includes an operation unit, a steering piston-and-cylinder assembly and an operating fluid switching unit. The operation unit causes a steering arm of a propelling unit to be operated with operation of a steering wheel installed in the boat. The steering piston-and-cylinder assembly is connected to an operating fluid supply pump and a drain tank and capable of being supplied with operating fluid. Its piston rod is coupled to the steering arm. The operating fluid switching unit is disposed between the steering piston-and-cylinder assembly on one hand and the operating fluid supply pump and the drain tank on the other hand, and it switches the flow of operating fluid with the operation of the operation unit. It includes a switching section having a poppet valve coupled to the operation unit. The operating fluid switching unit includes a switching section and a normally closed drain control section.