Abstract: A roller pump includes a stator with a pump bed formed therein, and a rotor for acting on a hose inserted into the pump bed in arcuate form. The ends of the hose are guided out of the pump bed in a crossed configuration.

Abstract: The invention relates to a roller pump consisting of a stator with a pump bed formed therein and a rotor for acting on a hose inserted into the pump bed in arcuate form. In accordance with the invention, the flow paths associated with the ends of the tube guided out of the pump bed cross.

Abstract: A method and a device for determining the effective delivery rate of a peristaltic pump with which a liquid is delivered inside an elastic hose pipe or for adjusting the speed of a peristaltic pump in order to match the effective delivery rate of the pump to the desired delivery rate may be characterized in that the effective delivery rate is calculated based on the nominal speed of the pump and the pressure inside the hose pipe upstream of the pump depending on the running time of the pump. The stroke volume of the pump may be multiplied by the nominal speed of the pump and the product from the stroke volume and the speed of the pump may be corrected by a correction function, thereby determining the effective delivery rate of the pump.

Abstract: The invention relates to a method and a device for monitoring a flow of liquid for the presence of air bubbles, in particular the blood flowing in an extracorporeal blood circuit of an extracorporeal blood treatment device. The air bubbles are detected by an ultrasound measurement and the ultrasound signals received in a continuous sequence of time intervals are each compared to a predetermined reference level. When the amplitude of the ultrasound signal, or a parameter correlating to the amplitude of the ultrasound signal, is less than the predetermined reference level, the presence of a defined volume of air is determined. When the number of times the ultrasound signal is less that the predetermined reference value if is greater than the set limit value, it is determined that a critical volume of air is present in the patient's blood and the dialysis is stopped.

Abstract: The invention relates to a roller pump consisting of a stator with a pump bed formed therein and a rotor for acting on a hose inserted into the pump bed in arcuate form. In accordance with the invention, the ends of the tube guided out of the pump bed cross.

Abstract: The invention relates to a roller pump consisting of a stator with a pump bed formed therein and a rotor for acting on a hose inserted into the pump bed in arcuate form. In accordance with the invention, the ends of the tube guided out of the pump bed cross.

Abstract: The invention relates to a method for monitoring the supply of substitution liquid during an extracorporeal blood treatment and to an extracorporeal blood treatment unit equipped with a device for monitoring the supply of substitution liquid. The monitoring of the supply of substitution liquid is based on the measurement of pressure waves, which are generated by the substitution liquid pump, in the extracorporeal blood circulation system. A disturbance in the supply of substitution liquid is inferred when the amplitude of the pressure waves exceeds a predetermined limit value. The amplitude of the pressure waves is preferably monitored in the venous blood line.

Abstract: A roller pump includes a stator with a pump bed formed therein, and a rotor for acting on a hose inserted into the pump bed in arcuate form. The ends of the hose are guided out of the pump bed in a crossed configuration.

Abstract: A method and a device for determining the effective delivery rate of a peristaltic pump with which a liquid is delivered inside an elastic hose pipe or for adjusting the speed of a peristaltic pump in order to match the effective delivery rate of the pump to the desired delivery rate may be characterized in that the effective delivery rate is calculated based on the nominal speed of the pump and the pressure inside the hose pipe upstream of the pump depending on the running time of the pump. The stroke volume of the pump may be multiplied by the nominal speed of the pump and the product from the stroke volume and the speed of the pump may be corrected by a correction function, thereby determining the effective delivery rate of the pump.

Abstract: The invention relates to a method and a device for monitoring a flow of liquid for the presence of air bubbles, in particular the blood flowing in an extracorporeal blood circuit of an extracorporeal blood treatment device. The air bubbles are detected by an ultrasound measurement and the ultrasound signals received in a continuous sequence of time intervals are each compared to a predetermined reference level. When the amplitude of the ultrasound signal, or a parameter correlating to the amplitude of the ultrasound signal, is less than the predetermined reference level, the presence of a defined volume of air is determined. When the number of times the ultrasound signal is less that the predetermined reference value if is greater than the set limit value, it is determined that a critical volume of air is present in the patient's blood and the dialysis is stopped.

Abstract: The invention relates to a roller pump consisting of a stator with a pump bed formed therein and a rotor for acting on a hose inserted into the pump bed in arcuate form. In accordance with the invention, the ends of the tube guided out of the pump bed cross.

Abstract: The invention relates to a method for monitoring the supply of substitution liquid during an extracorporeal blood treatment and to an extracorporeal blood treatment unit equipped with a device for monitoring the supply of substitution liquid. The monitoring of the supply of substitution liquid is based on the measurement of pressure waves, which are generated by the substitution liquid pump, in the extracorporeal blood circulation system. A disturbance in the supply of substitution liquid is inferred when the amplitude of the pressure waves exceeds a predetermined limit value. The amplitude of the pressure waves is preferably monitored in the venous blood line.

Abstract: A device for removing gases from fluids, in particular from a dialyzing fluid, includes a container, which in the position of normal use is provided with a bottom first orifice and a bottom second orifice. Disposed inside the container is a partition wall which divides the container into a first chamber having the first orifice and a second chamber having the second orifice. The partition wall extends from the container bottom up to near the container cover, forming a gap-shaped interstitial space between the first and second chamber, and the container cover. Provision is made in the container cover for a venting orifice that is sealed by a hydrophobic filter. In one preferred embodiment, the first and second chamber form a tube-in-tube arrangement. The device according to the invention allows for a high separation rate to be achieved with a compact and simple design.

Abstract: A method and device for accurately determining the volume of and replacing ultrafiltrate in hemodiafiltration using an ultrafiltrate balance chamber that is subdivided by a movable partition into two balance chamber halves. The two balance-chamber halves being alternately filled, one with ultrafiltrate and the other with substituate, such that the volume of ultrafiltrate is balanced against the volume of substituate. The filling of one chamber with ultrafiltrate or substituate displaces an equal volume of substituate or ultrafiltrate from the other chamber half and diverts the displaced ultrafiltrate or substituate from the balance chamber. The filling volume of the ultrafiltrate balance chamber is used to determine the ultrafiltrate volume or the volume of substituate.

Abstract: A method for testing filters arranged in the dialysis solution system of an extracorporeal blood treatment apparatus is described, in which the filter membrane being tested is fully wetted with an aqueous solution, in which the branch of the dialysis solution system housing one of the two chambers of the filter being tested is closed off from the remaining branches, in which gas is conducted into the closed-off branch until a predetermined excess pressure has formed in the one chamber of the filter being tested. Simultaneously, the aqueous solution previously conducted into the chamber to fully wet the filter membrane is expelled. The excess pressure in the one chamber of the filter is monitored, in which the pressure drop per unit time is compared with a given reference value which is characteristic of a fully intact filter membrane. If the reference value is exceeded, this provides and indication of a leak in the filter membrane.

Abstract: Apparatus for measuring the pressure of a fluid includes a first pressure transmission element in form of a membrane in contact with a pressure sensor, and a second pressure transmission element in form of a membrane which is acted upon by a fluid whose pressure is to be determined. The first membrane has a peripheral area which is pressed against the second membrane in such a manner that the space between the first and second membranes is sealed off from outside and is of a size as small as possible. Both membranes thus move in synchronism in dependence of the fluid pressure so that positive as well as negative pressures can be measured.