Abstract: A method for determining the particle concentration of a continuous medium in a receptacle, in which, a light beam from a light source is first directed through a particle-loaded, continuous medium, to the light-sensitive surface of a position-sensitive sensor, the light beam being so directed at the light-sensitive surface that the light scattered by the particles assuming, on the average, a different position than the unscattered light. The deviation of the midpoint of the scattered light on the light-sensitive surface from the midpoint of the unscattered light is subsequently determined, and this deviation is correlated to a specific particle concentration.

Abstract: The invention relates to a blood donation device with a receptacle for a blood donation container and a control section at which utensils required by the operator can be accommodated and/or by means of which parameters of the donation process can be varied, detected and/or retrieved. Bending of the operator to the blood donation device which is normally arranged in the region of the floor is avoided according to the invention by the fact that the control section is arranged in an elevated position with respect to the receptacle of the blood donation device.

Abstract: A magnetic gear having first and second carrier each having a plurality of magnetic poles arranged in a circle and separated by a distance, with the north and south poles arranged in alternation. Flux-carrying connecting pieces are provided on a third carrier to magnetically couple the first and second carriers. A centrifuge for centrifuging biological fluids, especially blood, having such a magnetic gear includes a first carrier in a stationary mount on a frame, while the third carrier is a rotating frame in a rotating mount on the frame. The second carrier is a separation unit mounted on the rotating frame. The centrifuge using the magnetic gear allows maintenance-free operation at a high rpm and with low noise, requiring a relatively low driving power.

Abstract: A device is described for measuring changes in parameters in transparent objects, in particular for medical applications. For universal use in various applications, the device includes a light source, an optical line sensor which detects the intensity of the light of the light source passing through the object as a function of location in at least one extension direction of the object, and a computer unit which compares the distribution of the light intensities detected by the optical line sensor as a function of location with at least one predetermined reference distribution. According to another embodiment, the light source supplies approximately parallel light, and the computer unit shapes the first derivation according to location of the distribution of the light intensities detected by the optical line sensor. The device is designed so that the different light sources can be easily replaced or combined.

Abstract: A method for determining the particle concentration of a continuous medium in a receptacle, in which, a light beam from a light source is first directed through a particle-loaded, continuous medium, to the light-sensitive surface of a position-sensitive sensor, the light beam being so directed at the light-sensitive surface that the light scattered by the particles assuming, on the average, a different position than the unscattered light. The deviation of the midpoint of the scattered light on the light-sensitive surface from the midpoint of the unscattered light is subsequently determined, and this deviation is correlated to a specific particle concentration.

Abstract: A centrifuge, especially a flow-through centrifuge free of rotating seals, for centrifuging biological fluids has a stand on which a frame (1) is rotatably mounted. A centrifuge chamber (3) is rotatably mounted on the rotating frame (1) to rotate about the axis of the latter. The centrifuge chamber (3) is driven in the same direction of rotation as the frame (1) but at twice the rotational speed. Coupling elements which are engaged by magnetic forces and are designed in the manner of a clutch disk or a gearwheel are used to transmit the torque to the centrifuge chamber or the rotating frame. Force is transmitted in a non-contact and wear-free manner. No lubrication is necessary, which also reduces the buildup of dust and dirt. In addition, there is little generation of noise.

Abstract: An ultrasonic transmitter, particularly for an air bubble detector, having a transmitting stage and an ultrasonic crystal. The transmitting stage includes a multivibrator having a time-base circuit with two stable output states. A timing element is interconnected in the feedback loop of the time-base circuit. An ultrasonic crystal is interconnected with the feedback loop of the time-base circuit so that the electrical circuit oscillates at or near a resonance frequency of the ultrasonic crystal. The ultrasonic crystal may be disconnected so that the multivibrator oscillates automatically at its own natural frequency.

Abstract: The invention relates to an unbalance detector, such as for a centrifuge. The invention preferably comprises a pressure-sensitive static sensor, preferably in the form of a piezoelectric cable, which preferably is mounted on a stationary casing part and delivers an imbalance signal when it comes in mechanical contact with the rotor which has been deflected because of an imbalance. As an alternative, the sensor can also be mounted on the rotor and deliver the unbalance signal on coming in mechanical contact with the stationary casing part. According to another embodiment of the invention, the analysis stage for the unbalance signal has a test stage or simulation stage for testing the functionality of the unbalance detector.

Abstract: A centrifuge has a drive unit, a separation chamber which can be inserted into the drive unit, and a scanning device for recognizing the position of the separation chamber which is rotated by the drive unit. The separation chamber is constructed as a disposable chamber and is provided with a marker element which is arranged in a scanning region extending annularly around the rotation axis of the chamber. The position of a phase boundary window is detected by sensing the position of the marker with a phase boundary detector portion of the scanning device whereby the chamber can be inserted into the drive unit in any position.

Abstract: A photoelectric arrangement for the determination of a substance spectrally differently absorbing light in a specimen (1) comprising two alternately switched on light sources (2,3) of different wavelengths matched to the absorption maximum or minimum of the substance, two photoelectric receivers (5,6) arranged in such a manner with respect to the specimen that the one receiver (measuring receiver 5) receives light which traverses the specimen and the other receiver (reference receiver 6) receives light of the light sources directly and an electronic control and evaluation circuit following the photoelectric receivers and controlling the light sources for the determination of the different absorption typical for the substance at the two wavelengths, wherein the control and evaluation circuit comprises a light circuit (7,8,10,11a,11b) following the reference receiver (6) for determining light amounts transmitted by the light sources and defining the switchover instant for the light sources on reaching a predete

Abstract: Failsafe logic circuits, for instance AND-, NOR-, NAND- and OR-circuits are devised at which at least one signal input is connected to a signal output via an optocoupler. Herewith dimensioning problems with respect to transistors and coupling capacitors as known from conventional failsafe logic circuits do not appear. Further on an optocoupler cannot fail in such a manner that between a photodiode and a phototransistor a galvanic coupling may arise.

Abstract: Method of separating blood, in particular for recovering thrombocytes and/or leucocytes, the whole blood coming from the donor being separated in a separation means of a centrifuge into an erythrocyte fraction, cell-poor plasma, a thrombocyte fraction and/or possibly a leucocyte fraction, the separated fractions of the blood being discharged via a flexible tubing system of discharge lines out of the separation chambers of the centrifuge and constantly predetermined amounts of separated cell-poor plasma returned to the whole blood to be separated or to the already separated erythrocytes in the separation chamber, and a separation apparatus for carrying out the method comprising a separator having one or more separating chambers connected together and a flexible tubing system which includes a supply line (1, 2) for the supply of the whole blood to be separated to the separator and discharge lines each for the separate discharge of the erythrocyte fraction (10), the cell-poor plasma (3, 5), the thrombocyte fract

Abstract: A peristaltically operating roller pump, in particular a hose pump for medical technology, comprises a pump bed (25) whose bearing wall (28) in the exit region (31) has a curvature which is in the same sense as the circular path (33a) of a roller (33) mounted on a pump rotor (1) and which has a radius of curvature which is constant with respect to the circular path (33a) or gradually increases in the direction of rotation of the roller (33). The pump rotor (1) comprises a gear connection so that a constrained radial movement of a roller is converted to a corresponding follow-up movement of the other rollers or roller. By this combination of pump bed and pump rotor pressure peaks and fluctuations of the flow rate are effectively prevented.

Abstract: A plurality of scanning regions (22) are disposed about the anticipated region of a phase boundary (32) of two media. The change in position of the phase boundary (32) is detected by a scanning means (18) with which each scanning region (22) is scanned and a signal is generated for each of the scanning regions (22). The first media is more radiation-permeable than the second media. A beam path is generated by the scanning means and is detected and evaluated by a discriminator circuit as a logic one. The second media is less radiation-permeable than the first media. The absence of a beam path corresponding to scanning regions in the second media is evaluated by the discriminator circuit as a logic zero. The number of signals per measuring cycle is compared against the actual number of scanning regions (22) to locate and control the position of the phase boundary (32).

Abstract: A roller pump (1) comprises a stator member (2) in which a pump bed (3) is formed with specific geometry. In the interior of the pump bed (3) a rotor (6) is rotatably mounted. A pump hose (10) can be inserted into the pump bed (3), said hose being curved in loop-like manner and its two ends being combined in immediate vicinity to each other in a connecting piece (11). The connecting piece (11) can be fixed in location in the stator member (2), the arrangement in the stator member (2) being uniquely defined by cooperation of a location tongue (23) and a location slot (22). Interchanging of the pressure-side and suction-side connection is thus impossible. A holding-down member (24) arranged on the rotor (6) permits automatic insertion and ejection of the pump hose (10) or hose system (9).