A surface mount chip package comprises a package housing made of a prescribed resin, which is formed to cover a semiconductor chip while avoiding a plurality of conductors extending from the semiconductor chip. The controller changes the rotation speed of the engine 2 to reduce fuel consumption according to power generated by the engine 2, and changes displacement of the hydraulic pump 1 based on the rotation speed of the engine 2, the dial position of the engine control dial 4 and the amount of operation on the operating lever 5. A height of the accommodating surface portion is an approximately the same height as that of another socket which is disposed next to the socket.