Abstract: In a photoelectric conversion/connection device (100) including an optical element (320), a mounting board (310) on which the optical element is mounted, and an optical connector (400) which is connected to the mounting board so as to be optically connected to the optical element, the optical connector (400) is arranged on a surface (310a) opposite to a mounting surface (310b) of the mounting board (310) and the optical element (320) is exposed. The photoelectric conversion/connection device (100) includes a motherboard (210) having a main surface (210a) and an electric connector (220) to be mounted on the main surface of the motherboard. The electric connector (220) is detachably connected to the mounting board (310).

Abstract: In a photoelectric conversion/connection device (100) including an optical element (320), a mounting board (310) on which the optical element is mounted, and an optical connector (400) which is connected to the mounting board so as to be optically connected to the optical element, the optical connector (400) is arranged on a surface (310a) opposite to a mounting surface (310b) of the mounting board (310) and the optical element (320) is exposed. The photoelectric conversion/connection device (100) includes a motherboard (210) having a main surface (210a) and an electric connector (220) to be mounted on the main surface of the motherboard. The electric connector (220) is detachably connected to the mounting board (310).

Abstract: A hydraulic drive system comprises a check valve cb1 for detecting a pressure on the outlet side of a pressure compensating device VB1, a maximum load pressure detecting line SL1 for selecting higher one of the pressure detected by the check valve cb1 and a load pressure of an actuator associated with a hydraulic pump P1 and supplying it as a signal pressure, a check valve cb2 for detecting a pressure on the outlet side of a pressure compensating device VB2, a maximum load pressure detecting line SL2 for selecting higher one of the pressure detected by the check valve cb2 and a load pressure of an actuator associated with a hydraulic pump P2 and supplying it as a signal pressure independently of the maximum load pressure detecting line SL1, and a passage 300 for joining hydraulic fluids supplied from the hydraulic pumps P1, P2 and passing through variable restrictors RB1, RB2 with each other and supplying it to an actuator B. Mutual independence between the two hydraulic pumps P1, P2 can be thereby ensured.