Abstract: A method of inspecting district heating pipes consists in introducing into the pipe a vehicle including an uninflated balloon and a pulley in which a cable is inserted. The vehicle is immobilized in the pipe by inflating the balloon. A sensor is moved in the pipe by fixing it to one end of the cable and pulling on the other end of the cable to move the sensor toward the immobilized vehicle in order to inspect the pipe. The vehicle includes a parachute and is propelled in the pipe by introducing into the pipe a fluid under pressure that acts on the parachute. The balloon is deflated when the sensor reaches the vehicle immobilized in the pipe. The vehicle and the sensor are withdrawn from the pipe by pulling on the end of the cable so that the inspection is carried out during the return travel of the vehicle and the sensor. With this method, the inspection can be carried out with access from only one end of the pipe.

Abstract: A sensor for detecting defects in a component includes an electric coil fed with a varying electrical current to create a varying magnetic field penetrating at least partly into the component under test, and a defect detector including a magnetoresistor. The above components are accommodated in a protective housing having a detection face disposed near and parallel to a surface of the component under test. The coil has its axis &Dgr; perpendicular to the detection face and the magnetoresistor is in the vicinity of the detection face. The magnetoresistor is a giant magnetoresistor and is disposed so that its sensitivity axis &Dgr;1 sensitive to variations in a magnetic field is parallel to the detection face of the housing.

Abstract: A method of inspecting district heating pipes consists in introducing into the pipe a vehicle including an uninflated balloon and a pulley in which a cable is inserted. The vehicle is immobilized in the pipe by inflating the balloon. A sensor is moved in the pipe by fixing it to one end of the cable and pulling on the other end of the cable to move the sensor toward the immobilized vehicle in order to inspect the pipe. The vehicle includes a parachute and is propelled in the pipe by introducing into the pipe a fluid under pressure that acts on the parachute. The balloon is deflated when the sensor reaches the vehicle immobilized in the pipe. The vehicle and the sensor are withdrawn from the pipe by pulling on the end of the cable so that the inspection is carried out during the return travel of the vehicle and the sensor. With this method, the inspection can be carried out with access from only one end of the pipe.

Abstract: A sensor for detecting defects in a component includes an electric coil fed with a varying electrical current to create a varying magnetic field penetrating at least partly into the component under test, and a defect detector including a magnetoresistor. The above components are accommodated in a protective housing having a detection face disposed near and parallel to a surface of the component under test. The coil has its axis &Dgr; perpendicular to the detection face and the magnetoresistor is in the vicinity of the detection face. The magnetoresistor is a giant magnetoresistor and is disposed so that its sensitivity axis &Dgr;1 sensitive to variations in a magnetic field is parallel to the detection face of the housing.

Abstract: A device for inspecting a part by eddy currents, the device comprising at least one measurement bridge having an active coil which is connected between a first terminal and a second terminal, and a reference circuit which is connected between said second terminal and a third terminal, said first and third terminals being for connection to an AC voltage generator so that an alternating magnetic field is generated by the active coil in the part to be inspected in order to enable any variation in the impedance of the active coil on passing over a defect in a part under inspection to be detected by analyzing an output voltage of the device, wherein the reference circuit is a reference coil identical to the active coil, wherein the first terminal and the third terminal are for receiving voltages applied by the AC voltage generator which are equal in value and of opposite signs relative to a neutral phase of said generator, the output voltage being the voltage read between said second terminal and said neutral phas

Abstract: The present invention relates to a redundant process control system including at least one control unit (PLC1) which produces an output signal (S1) resulting from a control function being applied to a set of input signals (E1). In addition, the system includes at least one test member (TES1) that is different from said control unit, which test member produces a test signal resulting from said control function being applied to said set of input signals (E1) and generates an alarm (AL1) whenever there is a difference between said test signal and the corresponding output signal (S1).

Abstract: A device for displacing a member in a graduated and motor-driven manner inside a tube that is external to the device, the member being displaced from one end of the tube, the displacement being evaluated by at least one position encoder delivering information on the position of the member placed at one end of a tubular element which is mounted to move in translation on a support body for supporting the device. The tubular element is in the form of a member-carrying worm which is provided with longitudinal toothed racks on its periphery. The worm is displaced in translation relative to the body which carries it under the action of a first toothed belt which is mounted on the support body, which is driven by a motor fixed to the body, and which is meshed with one of the racks. Another of the racks meshes with a second toothed belt which entrains a position encoder fixed to the body.

Abstract: A track-guided transport system with power and data transmission and used for conveying goods. The transport system is provided with a transport element having drive and track-guide elements; storage, input and output units for goods; and a data processing and transmission unit. The transport element is provided with a transmission head as a secondary element for transferring power from a primary circuit laid along the track, the transmission head is mounted on the vehicle comprising a ferrite core and a secondary winding surrounding the core and magnetically is coupled to the primary circuit. An adjustable and controllable drive unit may be provided for forward motion; and a device may be provided for the forward motion for low-friction compensation of gravity and to ensure low-friction sliding along a track, as well as track-guide elements.

Abstract: An earth-leakage monitoring method for a power distribution system, and in particular a DC 4-rail traction system, incorporating a pair of current-conductors (current rails) and an earth reference (a pair of running rails or an earthing system), comprises measuring the conductor-to-earth voltage for each conductor; forming a ratio of these voltages; connecting a known resistance between one conductor and earth; re-measuring the two conductor-to-earth voltages; forming a new voltage ratio, and calculating the value of leakage resistance existing between each conductor and earth using the known resistance value and the two voltage ratios.

Abstract: A transformer has its primary windings connected in series with the pumping motor and has secondary windings powering in cascade a rectifier and a voltage limiter regulating the voltage supplied to the auxiliary equipment by diverting excess current supplied by said secondary windings.

Abstract: The subject matter of the invention is a process for controlling a multiplicity of spray tools for the surface coating of vehicles or parts thereof. With stored program control, the settings for the multiplicity of spray tool which determine the paint flow through each tool are issued centrally to the control elements associated with the spray tools. The trajectory points for the tools, which are stored with coarse spacing or obtained by coarse interpolation from already stored trajectory points, are applied as reference values to the attitude controllers serving each spray tool; from the said position controllers, additional trajectory points are determined by fine interpolation between the transmitted trajectory points and processed in the position controller by means of actual position values.

Abstract: A method is described for ordering a plurality of messages from a plurality of sources wherein, in order for all the application processes to receive the messages in the same order, a single relay process common to all the sources is selected from the application processes, the other application processes constituting slave processes. All messages broadcast by the sources are rebroadcast from the relay process to all the application processes, including the relay process. The relay process processes data from all messages that it rebroadcasts. The slave process processes only data from messages received via the relay process, data from messages received directly from the sources not being processed. Applications include data processing systems, in particular where part of the software is replicated.

Abstract: A method of scheduling tasks subject to timing and succession constraints essentially comprises grouping the tasks in layers according to succession constraints and scheduling the tasks layer by layer in increasing layer order up to the last layer, if possible, and then deciding that the resulting scheduling succeeds. If the scheduling achieved in a layer other than the first layer does not satisfy one or more constraints applying to a task belonging to the current layer, the method reschedules a layer containing a predecessor task corresponding to an unsatisfied constraint, schedules or reschedules all the other layers higher than the layer of the predecessor task, up to the last layer, if possible, and then decides that the resulting scheduling succeeds. Applications include scheduling of transmission of information on an industrial data bus.

Abstract: A method for automatically coating objects with a spraying device which includes at least one atomizer that is moved along paths determined by programs. For respective objects or segments of objects, which essentially differ with respect to the dimensions, a program is provided which is modified as a function of the length of the respective object or segment, which length is allocated to a direction of a Cartesian coordinate system, for predetermining the path of the atomizer in the direction of the length of the object. By means of dimension data that are inserted into the program, the paths to be followed by the atomizer are constantly adapted along the predetermined path in at least one direction that extends at a right angle to this direction.

Abstract: An electric machine control system includes a torque smoothing device including a torque monitoring device connected to the electric machine and supplying torque signals. A smoothing processor receives the torque signals and receives at least one torque reference signal and produces torque smoothing signals. A smoothing generator receives the smoothing signals and supplies smoothing electric power to the machine to make its torque conform to the torque reference.

Abstract: A window manager for a windowing system includes a window server to command the display on screen of first windows reserved by client programs of the system. The window manager manages the disposition and the circulation of first windows within a second window reserved by the system. The server holds in memory a tree structure of windowing data on the basis of which the window server communicates with the screen window manager and with the client programs. This structure has a root defining the second window and nodes defining corresponding first windows. The window manager manages in the root a first list of identifiers of first windows and detects in each node the presence or the absence of control data. If control data is present in a node defining a particular first window, the window manager manages the disposition and the circulation of the first windows on the basis of second window data under the control of a client program.

Abstract: To protect a switching device having a possible open-circuit failure condition, an arrangement is featured in which a thyristor is connected in parallel with the main current-carrying terminals of the switching device to be protected. The thyristor is connected so that the forward current direction of the thyristor is the same as the normal current direction through the main terminals of the switching device. The arrangement provides for the thyristor to present an irreversible effective short-circuit when its normal parameter ratings are exceeded. The protection arrangement is particularly suitable for insulated-gate bipolar transistors (IGBT's) and preferably employs a pressure-packaged asymmetrical thyristor (ASCR) as the protection thyristor. The ASCR should be selected to withstand the normal (snubber-limited) dV/dt of the voltage across the switching device.

Abstract: The invention concerns a branch connector device for a shielded cable connecting a plurality of stations of a land network. The device comprises:a junction box (Bi) comprising a housing, an electromagnetic shield (EBi) and two entries for two respective sections (Ci, C'i) of the shielded cable;a connector (Mi) comprising a plurality of contacts and an electromagnetic shield.According to the invention the housing of the junction box forms the housing of the connector; the shield (EBi) of the junction box also forms the shield of the connector; and the conductors of each section of the cable are connected directly to the contacts of the connector. Applicable to industrial data processing.

Abstract: A process for introducing or displaying the adjustment parameters of a device for coating objects, particularly vehicles and vehicle bodies. The parameters are introduced on or off-line by a personal computer and displayed on the monitor graphically and alphanumerically in a manner which provides a survey of a series of parameters in mutual relationship.

Abstract: A power converter device for supplying direct current to an electric arc furnace comprises at least one transformer with its primary fed with a three-phase alternating current and delivering to at least one secondary a three-phase current applied to a rectifier system outputting to the load a rectified voltage and current. The rectifier system comprises controlled semiconductors for each secondary and a freewheel circuit. The controlled semiconductors are triggered with essentially variable firing angles, modified to increase the duration of conduction in the freewheel circuit whilst reducing the duration of conduction in the triggered semiconductors, and vice versa, so as to deliver to the load a substantially constant active power or reactive power despite variations in the impedance of the load.