Abstract: A method of message transmission between users in a distributed system with token passing includes a special token procedure in order to achieve consistent message transmission, even in the case of a fault. The special token procedure is based on a coincidence of monitoring and information states of the users. In the case of an error, a logical resumption, which is derived from a consecutive sequence number, is carried out without adversely affecting data consistency. The method can be implemented in different versions, that is with information passing of user data in the form of a ring or the transmission of user data in physical multicast and the passing of associated check information in the form of a ring. The method can be used in supervisory control installations.

Abstract: A method for fault-tolerant communication under strictly real-time conditions in a local network uses a double bus architecture for reporting faults and for tolerating global bus faults. An active fault detection and notification mechanism is provided in order to safeguard consistency in the case of a fault and in order to comply with time limits regarding transmission of data. During fault-free operation, all of the process data are transmitted in one of the redundant bus systems and status information is transmitted in the other bus system. In the case of a fault, each bus is used as a watchdog bus in order to notify the network subscribers of faults occurring in the respective other bus system. The method can be used in process-oriented control and automation systems which have stringent requirements regarding reliability and real-time behavior.

Abstract: A filter for the filtration of extraction beverages includes a disk having a plurality of apertures through which the beverage extracted from the material to be extracted passes form the afflux side to the efflux side. Each aperture is formed by cut edges in the disk and by bending a cut edge away from the surface of the disk to form a roof-shaped dome. The filter is formed by a single punching, bending and embossing operation without scrap slug being produced.

Abstract: The invention concerns a sampling device for a mobile analysis unit, in particular a mass spectrometer (13), used for the purpose of monitoring chemical substances on ground surfaces. It possesses at least one sampling wheel which revolves around an axle and which consists of a silicone tire (5) for picking up molecules of substances to be monitored and a wheel rim (6) upon which the silicone tire is fitted. The wheel rim (6) is made of metal such as stainless steel or aluminum. This means that on the one hand contamination of the silicone tire (5) by vapors from the wheel rims (6), in the course of long-term storage of the sampling wheels in airtight, closed storage containers, is prevented. On the other hand, the invention facilitates an advantageous construction of the wheel rim (6), involving the mounting of two, thin-walled rim halves (9) with rivet holes.

Abstract: In a rotary printing machine with directly driven cylinders and at least one directly driven folding unit (12), those drives of the cylinders and their drive controllers which can be assigned to a paper web are combined to form printing-station groups (2). The printing-station groups (2a-d) are connected to one another, to the folding unit (12) and to the operating and data-processing unit (1) via a data bus (3). Within the printing-station group (2), the individual drives of the cylinders and their drive controllers are connected via a high-speed bus system. The printing-station groups (2a-d) acquire their position reference directly from the folding unit (12). The master control system (1) is now responsible only for the presetting of desired values and desired-value deviations and the processing of actual values.

Abstract: A sampling device for inspection vehicles equipped with an environmental inspection system, the system comprising an analyzer having a receiving head (21), to which the substances to be examined are supplied by means of a movable collecting body (4) having a ground-engageable contact surface. The collecting body is formed by a rope-like material (4) which is wound up on a supply drum (2) and passed between two rollers (10, 11) arranged at a certain distance therefrom. By displacing the material (4) in its longitudinal direction, the material can be moved into a first position in which an end section (41) of the material hangs down and contacts the ground (42), and a second position in which the end section (41), which had been in contact with the ground (42), is positioned opposite the receiving head (21). Consumed end portions (41) can be cut off by means of a separating device.

Abstract: A buckling protection control system for articulated vehicles, especially for articulated buses is disclosed. Double acting piston cylinder units are interposed between vehicular sections at the hinged connection therebetween to forceably dampen and control the relative angular movement of the vehicular sections during driving of the vehicle. In addition to controlling the buckling movements during proper driver operation of the vehicle, the control system of the invention includes an arrangement for responding to situations where a driver, as a result of a panic reaction, sharply or rapidly steers the vehicle. For this purpose, the invention includes a computer control system which determines a maximum buckling angle value K-max(V) which is dependent on the vehicle velocity V. Irrespective of other driving conditions, the buckling angle is prevented from exceeding this maximum buckling angle K-max(V).

Abstract: The two dimensional processing path along which the electron beam of a welder is to be deflected during a processing cycle is approximated by a sequence of points separated by predetermined distances from one another. The deflection signals for the beam are derived from analog signals having levels corresponding to the points, and interpolation there between. The rate of interpolation depends on the distance between the points and time intervals specified so as to create preselected beam velocities. Since a weld is improved when there is micromotion of the beam around the processing, a modulation path generator is also provided. Since the coordinates furnished by this modulation path generator are in a fixed coordinate system and the micromotion of the beam is relative to the processing path, a coordinate rotation is carried out before the modulation signals are superimposed upon the processing path deflection signals.

Abstract: A welder utilizes a focussed electron beam which is deflected along the processing path required to weld two pieces together and is also oscillated about the processing path in accordance with a modulation curve. The modulation curve is approximated by a sequence of points. The coordinates of the points in a predetermined coordinate system are read out sequentially from a digital storage and converted to analog signals. The analog signals are subjected to low pass filtering and then applied to the deflection system for the electron beam. The cut-off frequency of the low pass filter is a predetermined multiple of the readout frequency of the digital data. When the velocity of the beam along the modulation curve changes, the cut-off frequency and the readout frequency are adjusted simultaneously. Additionally, the position of the focus and/or the intensity of the electron beam can be varied as the beam traces out the modulation curve.

Abstract: An anti-buckling control system is disclosed for articulated vehicles, especially articulated busses. Two double acting piston-cylinder units are interposed in the pivot connection between the forward and following vehicular units for applying resistance forces against hinged or buckling movement of the vehicular units with respect to one another. A computerized control unit is provided for controlling the hydraulic circuit for the piston-cylinder units so that they apply resistance forces tending to direct the buckling angle towards desired values determined in dependence upon the forward vehicular unit steering angle, the instantaneous buckling angle, and the vehicle velocity. The piston-cylinder units are disposed with their ends at one vehicle side closely adjacent one another and with their ends at the other vehicle side spaced from one another to form a V-shaped configuration.

Abstract: A multiple piston pump with a constant discharge capacity for liquid chromatographs comprises at least three piston-cylinder units (1,2,3), whereof the pistons (7) are driven through a non-linear drive by a motor (23) with a mutual phase displacement of 360.degree./n, when n represents the number of piston-cylinder units. A regulating system varies the speed of the motor (23) during each period or cycle of the piston movement in such a manner as to compensate for the non-linear drive so that the pressure of the liquid conveyed during each period or cycle remains at least approximately constant. The motor (23) can be constructed as a stepping motor, which is supplied with current pulses whereof the frequency determines the speed of the motor.

Abstract: A mixing chamber for liquids, which are supplied to the mixing chamber in measured quantities one after the other alternating over a period of time, in particular for liquid chromatographs is divided by a fine-pored filter plate (109) into two areas (105, 106). The inlet pipe (111) is connected to one area and the outlet pipe (112) is connected to the other of these areas. The two areas (105, 106) each widen out in a conical shape from the opening of the connected pipe (111) towards the filter plate (109). The filter plate (109) preferably consists of a steel or glass frit with a pore size in the range of 2 to 50 .mu.m.

Abstract: A spin resonance spectrometer having a sample vessel 83 for containing substances to be examined. Pipes 92, 93 for the supply and discharge of test substances and possibly rinsing media are connected to the sample vessel, the pipe serving for supplying substances being connected to the sample vessel 83 such that the direction of movement of the substance supplied, on entering the sample vessel 83, has a component directed tangentially with respect to the sample vessel. As a result the supplied substance rotates in the sample vessel. The supply pipe 92, 93 may open substantially tangentially into the sample vessel 83, or a connecting member 184 comprising at least approximately helical channels may be located between the pipe 192 and the sample vessel 183.