Abstract: To provide a pump device capable of limiting discharge of a fluid when the operation is stopped. A pump device (3) includes a casing (10), a movable member (30), a suction valve (41), a discharge valve (42), and a valve mechanism (50). The casing (10) includes a suction port (101), a discharge port (102), and a pump chamber (100). The movable member (30) is movable within the casing (10) and alternately performs suction and discharge of a fluid into and from the pump chamber (100). The discharge valve (42) is attached between the pump chamber (100) and the discharge port (102) and permits the fluid having a first pressure or higher to flow. The valve mechanism (50) is attached to the casing (10) and limits a flow of the fluid having a second pressure or lower.

Abstract: The pump device has a driving member with one end connected to a diaphragm and another end connected to a driving mechanism. The driving mechanism side end repeats reciprocating motion along first axial direction and oscillation in second axial direction. The diaphragm side end performs the reciprocating motion in the first axial direction, and a problem is that the diaphragm easily deteriorates to be cut in a direction in which the diaphragm can be easily stretched, for example, in the second axial direction for performing oscillation. By embedding the base fabric having the fiber which extends in the second axial direction into the diaphragm, the strength in the second axial direction and the durability can be improved. By providing the index part to indicate the second axial direction, the extending direction of the fiber of the base fabric embedded within the diaphragm becomes distinguishable.