Abstract: A flow means with a housing and a fan to generate a fluid flow within a pipe or hose line of an intake monitoring system. The fan can be connected to the pipe or hose line via connecting pieces and can be driven to rotateaxis . The invention creates a flow means (100) which enables the direction of flow to be reversed. Respective blocking means are assigned to the connecting pieces and can be moved from an intake position (PS), in which an intake region of the fan is connected to the respective connecting piece into an exhaust position (PB), in which an exhaust region of the fan is connected to the respective connecting piece so the flow within the pipe or hose line is in a first direction of flow (S1) or in a second direction of flow (S2) as a function of the position (PS, PB) of the blocking means.

Abstract: A device for determining flow parameters, particularly the temperature and flow speed and changes therein, in a fluid flow for monitoring and a fire recognition or oxygen measuring device provided with such a device are provided. A slow or sudden blockage, crack or break in a pipe system of an aspirative fire recognition device is recognized by a measurement technique, whereby an air flow sensor, operated with a constant excess temperature, is combined with a regulation algorithm, running in a microprocessor, for monitoring pipe system fluid flow or flow resistance. The required resistance of the air flow sensor can thus be calculated by an exact sensor calibration curve and a precise control loop formed. The measured values recorded by the air flow sensor are extremely reliable, such that changes in condition for the flow parameters provide information about the state of the pipe system or the intake system.

Abstract: The invention relates to a device for the determination of flow parameters of a fluid, in particular, the temperature and flow speed and changes therein, in a fluid flow for monitoring, a method for operating such a device, a determination method itself and a fire recognition or oxygen measuring device provided with such a device. The aim of the invention is the recognition of a slow or sudden blockage, crack or break in a pipe system (13) of an aspirative fire recognition device by means of a measurement technique, whereby an air flow sensor (1), operated with a constant excess temperature, is combined with a regulation algorithm, running in a microprocessor (4), for monitoring the fluid flow or the flow resistance in the pipe system (13). The required resistance of the air flow sensor (1) can thus be calculated according to an exact sensor calibration curve and a precise control loop (3) formed.