The invention relates to a fluid control device (7, 30) that comprises a fluid transfer chamber (17) and a first fluid conduit (13), a second fluid conduit (11) and a third fluid conduit (14) which are fluidly connected to the fluid transfer chamber (17). A control spool (15) is arranged movably inside the fluid transfer chamber (17) in a way that the first fluid conduit (13) and the third fluid conduit (14) can be selectively fluidly connected to the second fluid conduit (11) through said fluid transfer chamber (17). The control surfaces (19, 20) of the control spool (15) are arranged in the vicinity of the first fluid conduit (13) the third fluid conduit (14).

A hydraulic pump that allows a drive source to be started with a small torque includes a cylinder block having a plurality of cylinder bores and disposed so as to be rotatable. Pistons are each movably retained in an associated one of the cylinder bores. A swash plate controls the amount of movement of the pistons in accordance with the size of the tilt angle. A first pressing unit is configured for pressing the swash plate in such a direction as to reduce the tilt angle of the swash plate, and a second pressing unit is configured for pressing the swash plate to increase the tilt angle of the swash plate by the pressure supplied from the outside.