A valve apparatus of a valve system includes a long-sized elastic member a base end portion of which is fixed and a front end portion of which is brought into contact with a valve element and a movable member capable of moving in B1 and B2 directions actually linearly along a longitudinal direction B of the elastic member between both end portions of the elastic member and having a fulcrum portion for flexing the elastic member in C direction between the both end portions of the elastic member. The movable member is constituted by a slider linearly moved in accordance with a mover of a linear step motor element or rotation of a rotor of a rotary type step motor element.

A pressure-variable valve device which is adapted to be embedded in the human body and which is capable of changing a difference in pressure between an inlet-side and an outlet-side duct, the valve device including a rotating member capable of rotating around a central axis in directions to vary a set pressure for a valve, and a rotation control mechanism far controlling the rotation of the rotating member wherein the rotation control mechanism includes permanent magnet structure supported by the valve-device main body as to be capable of making a linear reciprocal translation in directions, and displacement transmission mechanisms, for rotating the rotating member in the direction corresponding to the direction of the translation of the permanent magnet structures. A set-pressure adjusting device includes a magnetic field generating mechanism which generates a magnetic field in which the permanent magnet structures cause the rotating member to rotate in the same direction.

A variable pressure valve apparatus has a case having a fluid inlet port and a fluid discharge port, a valve element for closing the fluid inlet port, a spring member disposed in the case for biasing the valve element to close the fluid inlet port, and a cam wheel for undergoing rotation to deform the spring member and thereby vary a biasing force applied to the valve element by the spring member. A feed ratchet is disposed in the case for undergoing movement to rotate the cam wheel. A shape memory alloy or a piezoelectric element undergoes extension movement to move the feed ratchet to thereby rotate the cam wheel to deform the spring member.

A pressure-variable valve device which is adapted to be embedded in the human body and which is capable of changing a difference in pressure between an inlet-side and an outlet-side duct, the valve device including a rotating member capable of rotating around a central axis in directions to vary a set pressure for a valve, and a rotation control mechanism for controlling the rotation of the rotating member, wherein the rotation control mechanism includes permanent magnet structures supported by the valve-device main body so as to be capable of making a linear reciprocal translation in directions, and displacement transmission mechanisms, for rotating the rotating member in the direction corresponding to the direction of the translation of the permanent magnet structures. A set-pressure adjusting device includes a magnetic field generating mechanism which generates a magnetic field in which the permanent magnet structures cause the rotating member to rotate in the same direction.

An adjustable hydrocephalus valve comprising a mechanical brake. The brake can be decoupled by pressing the valve housing percutaneously and allows in this state to adjust the opening characteristics of the valve by rotating externally disposed magnets. In order to detect the adjusted pressure or in order to adjust the pressure, specific adjustment or measuring pin principles are presented which simplify and at the same time improve the respective functions of measuring and adjusting.