Abstract: In an internal combustion engine (1) comprising an electroconductive cylinder head (3), a head cover (5) attached to the cylinder head, a fuel pump (11) attached to the cylinder head and including an electroconductive pump case electrically connected to the cylinder head, and an engine cover (30) positioned so as to oppose the head cover and the fuel pump, the engine cover includes a sound insulating material (31) in contact with the pump case.

Abstract: In an internal combustion engine (1) comprising an electroconductive cylinder head (3), a head cover (5) attached to the cylinder head, a fuel pump (11) attached to the cylinder head and including an electroconductive pump case electrically connected to the cylinder head, and an engine cover (30) positioned so as to oppose the head cover and the fuel pump, the engine cover includes a sound insulating material (31) in contact with the pump case.

Abstract: If a motor breaks down, an appropriate measure is taken according to the type pf the breakdown. If the breakdown is judged to be due to abnormal energization of the motor by electrical abnormality judgment means, a drive source for a hybrid compressor is secured while preventing an engine for traveling from stopping by compressor operation continuation means. If it is judged that the driven state of the motor is abnormal, the hybrid compressor is disconnected from the engine to protect the engine from mechanical abnormality of the hybrid compressor.

Abstract: A hybrid compressor achieving simplification in the structure and capable of driving the compression unit with ease is provided. An electromagnetic clutch unit (40) is provided at a rotating shaft (11) projecting out on one side of a compression unit (10) and an electric motor unit (70) is provided at the rotating shaft (11) projecting out on the other side of the compression unit (10), so that an electromagnetic clutch unit (40) in the prior art can be utilized directly. At the same time, since the electric motor unit (70) is provided at the rotating shaft (11) projecting out the other side of the compression unit (10), the electromagnetic clutch unit and the electric motor unit are set at the same rotating shaft (11) and the compression unit (10) and the electric motor unit (70) are positioned next to each other to reduce the torsional torque generated at the rotating shaft (11).

Abstract: In order to achieve a smooth shift between two drive sources, an electromagnetic clutch is engaged, when the rotation rate of the compression unit and the engine rotation rate match, to switch from motor drive to engine drive during engine startup or engine acceleration. The motor is driven before the electromagnetic clutch is cut off to switch from engine rive to motor drive during engine stop or engine deceleration.