Abstract: A hydraulic elevator power unit has an oiltight type detector for detecting the number of revolutions of an electric motor. A leak oil hole formed in a lower end portion of the detector is connected to a leak oil tank. The operating oil entering the detector is discharged through the leak oil hole, thereby preventing the detecting portion from being immersed in the operating oil.

Abstract: A hydraulic elevator for ascending and descending operation of a car by feeding or discharging a hydraulic fluid through a flow rate control device between a hydraulic pump connected to a reversible motor and a hydraulic cylinder. The elevator includes a one-way clutch connected between the motor and the hydraulic pump so as to transmit the normal driving force of the motor to the hydraulic pump in the ascending operation of the car and to apply regenerative braking force to the hydraulic pump in the descending operation of the car when the revolution speed of the hydraulic pump is increased over the synchronous speed of the reverse rotation of the motor.