Abstract: A method for attenuating aerodynamic noise from a landing gear may include researching a start point of a shear layer as a flow field characteristic of a region in the vicinity of an original shape of the landing gear, and adding a plate-shaped object in the vicinity of the start point, changing the start point to an edge portion of the plate-shaped object to make the shear layer farther from the original shape. Another method for attenuating aerodynamic noise from a landing gear may include researching a static pressure and an airflow velocity in a region in the vicinity of the landing gear as a flow field characteristic of the region, and adding a plate-shaped object covering a surface of the landing gear which is different from a surface facing an upstream side in an airflow direction, increasing the static pressure in the region to reduce the airflow velocity.

Abstract: The present invention is to provide an electro hydrostatic actuator excellent in a snubbing characteristic including a cylinder type actuator main body 1, a piston 2 having a piston rod, the piston slidingly moving in a cylinder of the actuator main body, a motor 18, a pump 19 for supplying fluid according to the rotation of the motor, a mechanism for adjusting a running amount of the fluid into and from the cylinder according to the motion of the piston, and a reservoir 8 for adjusting the supply of the fluid corresponding to a volume difference generated according to the motion of the piston, and a controller 17 which controls the number of revolutions of the motor according to the calculated load torque, and a snubbing control method used for this. An electro hydrostatic actuator of realizing a snubbing mechanism capable of increasing energy efficiency, when used for a landing gear retraction/extension device of an airplane, can be provided.

Abstract: If an engine undergoes high-load operations immediately after it is started up from its cold state, a thermostat is closed to inhibit passage of cooling water through the inside of the engine, and the cooling water stagnant in a cylinder head receives heat from a combustion chamber. Therefore, the cooling water will possibly boil. However, the thermostat is formed in such a manner that a valve body may be opened forcedly if the discharge flow rate of a water pump is greater than the flow rate in a normal use region. Therefore, in such a situation, the discharge flow rate of the water pump is increased greater than the flow rate in the normal use region to open the valve body with good response, thereby passing water into the engine quickly. This configuration prevents the cooling water stagnant in the cylinder head from boiling before the valve body is opened completely.

Abstract: The present invention is to provide an electro hydrostatic actuator excellent in a snubbing characteristic including a cylinder type actuator main body 1, a piston 2 having a piston rod, the piston slidingly moving in a cylinder of the actuator main body, a motor 18, a pump 19 for supplying fluid according to the rotation of the motor, a mechanism for adjusting a running amount of the fluid into and from the cylinder according to the motion of the piston, and a reservoir 8 for adjusting the supply of the fluid corresponding to a volume difference generated according to the motion of the piston, and a controller 17 which controls the number of revolutions of the motor according to the calculated load torque, and a snubbing control method used for this. An electro hydrostatic actuator of realizing a snubbing mechanism capable of increasing energy efficiency, when used for a landing gear retraction/extension device of an airplane, can be provided.