Fresenius Ag

Ulrich Faeser

Dieter Mahn

Hans-Dietrich Polaschegg

The invention relates to an apparatus for injecting fluid in which as delivery conduit portion a simple hose segment having the same diameter throughout is used which is subjected to the action of a total of three pump rams, thereby forming delivery chambers (9-11) by compression of the hose segment, one of the pump rams (14) performing in the completely closed state the function of an outlet valve whilst having a delivery function until complete closure of the corresponding hose cross-section. As a result, in a very simple technical manner a considerable uniformization of the delivery flow is achieved.

Apparatus for injecting fluids

The invention relates to an infusion syringe pump which by means of a motor-gear unit drives a linearly movable drive member which is in engagement with the syringe plunger of an infusion syringe. According to the invention a position-defining element is connected only to the linearly movable drive member which actuates the syringe plunger of the infusion syringe. The position-defining element is functionally coupled to an absolute displacement pickup which is preferably constructed as linear potentiometer. By the control means according to the invention the absolute position of the syringe plunger can be determined.

Infusion syringe pump

The tapped voltage representing the displacement and duration of a potentiometer in a joystick-type actuating element is applied to an analog to digital converter and the converted digital value is fed to preset inputs of a presettable digital counter which is set at its counting inputs by a clock generator. The overflow output of the presettable counter is connected to a load input of the presettable counter and to an up/down counter which controls a display or the like via decoding and driver circuits. A subtracting circuit is provided to subtract a preselected value from the converted digital value in order to provide a dead zone for a preselected range of the potentiometer.

Device for inputting numerical or alphanumerical data, respectively into

In an apparatus whose output power is monitored and controlled to avoid safety-endangering effects, such as medical equipment, a monitored control arrangement is provided which includes (1) a control circuit for controlling output power at a desired level as part of the test wherein the control circuit consists of circuit elements with known failure rates, (2) a monitoring circuit connected to the control circuit to monitor output power and, if output power exceeds a critical level, to disconnect the control circuit to limit the output power (the monitoring circuit should also include circuit elements having known failure behavior) and (3) a test circuit electrically connected to the monitoring circuit and to the control circuit whose function is to disable the control circuit and to control the output power while performing an initial test on the monitoring circuit, and also to enable the control circuit and release control over the output power after performing the initial test, the test circuit including a microcomputer.

Monitored control arrangement

Spray pump with a motor driven drive rod

A peristaltic pump, more specially for enteral nutrition or feeding has an electric motor and a wheel, on which rollers are supported, with axis crossing the axis of the electric motor so that the main dimension of the wheel in its radial direction and the main dimension of the electric motor in its axial direction are parallel to each other or in line with each other so that a specially flat mechanical design of the pump is produced. The shaft of the electric motor has a pinion for meshing with teeth in a radial plane on the outer edge of the wheel and driving it, this producing a high step-down ratio of 1:500 or even more. The wheel with the rollers may have a generally large diameter so that it may be run at a low speed quietly. With such a diameter of the support wheel and when the pump has a flat rectangular housing, empty corners will be present in the housing on the two sides of the electric motor, into which batteries or the like may be placed. The motor may, because of the great step-down ratio, be run at a high speed so that a mass produced motor may be used for the pump. The peristaltic pump with such a flat rectangular housing may be comfortably kept under the user's clothing without making itself seen.

Growing community of inventors

Kronberg, Germany

Ulrich Faeser