PURPOSE: To make braking time constant regardless of the revolution speed of a movable part and also make the value of the braking angle primarily proportional to the revolution speed by braking the rotary mechanism connected to a fluid pump while cutting off the fluid circuit in circulation.
CONSTITUTION: In a normal state, a solenoid valve 4 is kept excited, and oil is circulated in a fluid circuit 10A by means of a fluid pump 1 according to the rotation of a movable part 40. On the other hand, in an abnormal state, when the solenoid valve 4 is made to be non-excited, the fluid circuit 10A is closed, oil is prevented from flowing, but the fluid pump 1 continues to rotate until the stop of the movable part 40. Due to this rotation, oil is sent to the part of the fixed volume between the outlet of the fluid pump and the solenoid valve, generating pressure, as a result, braking torque is suddenly generated in the direction opposite to the rotation of a pump shaft. At this moment, braking torque increases with the increase in the revolution speed and decreases with the decrease in the resolution speed. Therefore, braking time becomes constant regardless of the revolution speed, and the values of the braking angle becomes proportional to the revolution speed.
KUMEGAWA SOICHI
FUJII MINORU
IINO KOSHIRO
TAKAHASHI HISAO
KUMEGAWA SOICHI
NIPPON SIGNAL CO LTD