Abstract: The present invention relates to a valve having a base body with a passage opening, a movable valve member for closing and opening the passage opening and an actuating mechanism for moving the valve member in order to open the passage opening. The actuating mechanism has at least two elements made from a shape memory alloy which are secured to the base body or a carrier body connected thereto, and can be alternately shortened in the event of the temperature rising above a threshold temperature and are connected to the valve member in such a way that the valve member can be moved from a position on the passage opening into a position alongside the passage opening when one element is shortened on one side and can be moved back into the position on the passage opening when the other element is shortened on one side.

Abstract: The present invention relates to a valve having a base body with a passage opening, a movable valve member for closing and opening the passage opening and an actuating mechanism for moving the valve member in order to open the passage opening. The actuating mechanism has at least two elements made from a shape memory alloy which are secured to the base body or a carrier body connected thereto, and can be alternately shortened in the event of the temperature rising above a threshold temperature and are connected to the valve member in such a way that the valve member can be moved from a position on the passage opening into a position alongside the passage opening when one element is shortened on one side and can be moved back into the position on the passage opening when the other element is shortened on one side.

Abstract: The present invention relates to a valve having a base body with a passage opening, a movable valve member for closing and opening the passage opening and an actuating mechanism for moving the valve member in order to open the passage opening. The actuating mechanism has at least two elements made from a shape memory alloy which are secured to the base body or a carrier body connected thereto, and can be alternately shortened in the event of the temperature rising above a threshold temperature and are connected to the valve member in such a way that the valve member can be moved from a position on the passage opening into a position alongside the passage opening when one element is shortened on one side and can be moved back into the position on the passage opening when the other element is shortened on one side.

Abstract: The present invention relates to a valve which comprises a base body with a passage opening, a movable valve member for closing and opening the passage opening and an actuating mechanism for moving the valve member in order to open the passage opening. The actuating mechanism comprises at least two elements made from a shape memory alloy which are secured to the base body or a carrier body connected thereto, and can be alternately shortened in the event of the temperature rising above a threshold temperature and are connected to the valve member in such a way that the valve member can be moved from a position on the passage opening into a position alongside the passage opening when one element is shortened on one side and can be moved back into the position on the passage opening when the other element is shortened on one side.

Abstract: The present invention relates to a process and device for determining the surface friction coefficients of bodies, in particular of catheters. In the invented process, the to-be-examined catheter (1) is pulled with a defined velocity through a gel-like viscoelastic substance (2) and the frictional force required therefor is measured. A defined pressure is applied to this viscoelastic substance in such a manner that a defined surface normal force acts on the catheter surface. By applying a given, defined pressure on the substance, the surface pressure on each area element of the catheter surface is precisely given and can be held constant. By holding the area to which pressure is applied constant, the entire acting normal force can also be held constant and the friction coefficient can be determined for any catheter diameter and for any catheter consistency. Determination of the friction coefficient is reproducible and only depends on the surface friction.

Abstract: Disclosed is an obstetric forceps for grasping a baby during childbirth, the forceps having blades which are approximately adapted to the shape of a baby's head, are made of a rigid material and have contact surfaces for grasping the baby's head, the contact surfaces being provided with at least one device for detecting the pressure prevailing between the contact surfaces and the baby's head.

Abstract: A sensor for non-invasive and continuous determination of the duration of arterial pulse waves is provided in which at least two spaced apart piezoelectric pressure sensors are disposed in succession in the flow direction of the artery, with the sensor being provided with pressure sensitive surfaces and being integrated in a casing. The piezoelectric pressure sensors are provided with a pressure-sensitive, strip-shaped surface, with the strips each being disposed in their longitudinal extension perpendicular to the flow direction of the artery. The casing is provided with at least two recesses adapted to the contours of the strip-shaped surfaces into which the pressure-sensitive, strip-shaped surfaces of the pressure sensors are disposed flush to the surface of the casing.