Abstract: The invention relates to a nestable trolley with a basket for holding goods, the rear side of which is formed by a flap (1) which is pivotable into the interior of the basket, the flap (1), for accommodating a child, having a supporting wall (2) having leg openings (6), and also a rear wall (3) and a seating plate (4), with further a cover (5) of changeable position being provided which hides the leg openings (6), so that an additional goods deposition area can be formed. The invention is distinguished in that the cover (5) is formed from a transparent material, or in that the cover (5) has openings (5.1).

Abstract: A method and an apparatus for the user-specific configuration of a communications port includes provisioning a default profile that references a predetermined user, assigning the default profile to a user-specific configuration profile that is assigned to the predetermined user, and configuring the communications port using the user-specific configuration profile.

Abstract: A charged particle device is provided comprising a charged particle source configured to direct charged particles in the direction of a specimen under examination and an imaging device configured to convert charged particles to an image representing the specimen. The imaging device comprises a detector defining a pixel array. The detector is configured to generate electric charges for individual pixels of the pixel array such that the electric charges collectively define the image. The imaging device is configured such that a portion of the pixel array can be transitioned between a partially masked state and a substantially unmasked state.

Abstract: A charged particle device is provided comprising a charged particle source configured to direct charged particles in the direction of a specimen under examination and an imaging device configured to convert charged particles to an image representing the specimen. The imaging device comprises a detector defining a pixel array. The detector is configured to generate electric charges for individual pixels of the pixel array such that the electric charges collectively define the image. The imaging device is configured such that a portion of the pixel array can be transitioned between a partially masked state and a substantially unmasked state.

Abstract: A device comprising a television camera mounted inside the projection chamber of a transmission electron microscope with the imaging surface perpendicular to the optical axis of the microscope. The electron image is converted to a light image by high efficiency YAG transmission scintillator and transferred by a low loss fiber optic plate to a CCD imaging device. The camera is moved by a pneumatic piston between the operating position where it intercepts the electron beam and a position where the electron beam can pass unobstructed to the main microscope viewing screen.

Abstract: A device interposed between an electron microscope specimen holder and a microscope translation stage constructed of a special combination of materials arranged in such a manner that little or no specimen drift occurs when the temperature of the complete assembly is changed. In the first and more common arrangement, the device is placed in the nose of the standard microscope specimen holder and consists of a silica rod inside a metal tube, the material of the tube having a larger coefficient of thermal expansion than the material of the specimen rod. In the second, and less common arrangement the device is placed on the opposite side of the specimen away from the nose of the holder and consists of one tube, the material of which must have a larger coefficient of thermal expansion than the material of the specimen holder.

Abstract: An apparatus is proposed for regulating the idling rpm of internal combustion engines with externally supplied ignition. The apparatus includes a comparison circuit for set-point and actual rpm, and the idling rpm set-point value can be influenced in accordance with the actual rpm, time, operating voltage, temperature, and other variables as needed. The actual regulation is effected by means of a PID-regulator, whose individual characteristics may be established for processing data as desired, preferably in accordance with the rpm deviation. A limitation regulator furthermore serves to establish the respective maximum and/or minimum limitation of the adjustment member in accordance with operating characteristics.

Abstract: A fuel metering system having a .lambda. regulation device in which the delay periods known per se from the prior art are variable upon the switchover of the integration direction of an integrator included in the .lambda. regulation system. This variation produces a shortening of the delay period, as a result of which it is possible to prevent an excessive enrichment of the mixture. The invention relates to a controllable reduction of the individual delay signal as well as a control of the total duration of control exerted on the delay signals as they appear. The invention is independent of whether it is realized by either analog or digital circuit technology.

Abstract: An apparatus for the temperature control of a resistor used for measurement purposes, in particular, in combination with air flow rate measurement purposes, in particular, in combination with air flow rate measuring devices in internal combustion engines for a vehicle wherein the temperature of the resistor with current flowing through it is regulated during the measurement phase and in particular, operational states of the system provided with the apparatus and/or at particular times, the flow of current through the resistor is increased for the purpose of burning off dirt particles, which would falsify the measurement result, from the surface of the resistor which is formed, for example, as a hot wire. The apparatus includes a memory for picking up a signal such as whether a particular engine temperature is present at the beginning of one operational cycle or not and when this temperature is present, a red-hot heating procedure is omitted when the engine is subsequently turned off.

Abstract: A flow rate meter for measuring the flow rate of a fluid medium, especially that of the air aspirated by an internal combustion engine. A hot wire or film is placed in the air stream and is made part of an electrical circuit powered by the output of a differential amplifier. The voltage drop across the resistor is monitored at the input of the differential amplifier where it is compared with fixed or compensated values. In order to reduce the effect that airborne particles, which are deposited on the hot wire or film, have on the measuring characteristics of the apparatus, the wire or film are shaped so that their leading edge constitutes an area much smaller than the surfaces which are substantially parallel to the stream lines.

Abstract: The fuel-air mixture preparation system of an internal combustion engine is engaged by signals from a plurality of oxygen sensors located in the exhaust system of the engine. More than one sensor is provided to improve the quality of the output signals in unfavorable engine operation. The individual sensors are provided with comparators which make a comparison between the sensor output and a set-point signal. The output signals from the comparators are fed to a logically controlled coupling circuit which presents them in cyclic alternation to an integrating control circuit which provides a control signal to the final control element in the fuel mixture preparation system for changing the fuel-air ratio. The coupling circuit may also provide a signal based on the logical states of the individual sensor signals.

Abstract: A control circuit of a fuel management control system for internal combustion engines monitors the operation of an exhaust line sensor. When the oxygen sensor is perceived to be inoperative, for example, due to low ambient temperature, the previously closed loop control process governing the fuel management control signals is interrupted and a direct forward control process is substituted therefor. The reference voltage is changed during this time for eventual adaptation to the changeover to closed loop feedback control after the oxygen sensor again becomes operational.

Abstract: The fuel mixture preparation system of an internal combustion engine, especially a continuous fuel injection system, is engaged during intended engine accelerations by a pressure sensor in the induction manifold which responds to increasing manifold pressure to close a switch. The switch closure affects a pressure control valve that changes the control pressure in the fuel injection system and thereby causes temporary fuel enrichment until the differential pressure in the pressure sensor has returned to equilibrium. The signal from the pressure sensor may be extended arbitrarily by interposition of an electronic timing circuit which is constructed as an integrating circuit so that its output signal, when processed by a comparator, will produce a proportionally extended actuation signal for the control valve.

Abstract: A flow rate meter for measuring the flow rate of a fluid medium, especially that of the air aspirated by an internal combustion engine. A hot wire or film is placed in the air stream and is made part of an electrical circuit powered by the output of a differential amplifier. The voltage drop across the resistor is monitored at the input of the differential amplifier where it is compared with fixed or compensated values. In order to reduce the effect that airborne particles, which are deposited on the hot wire or film, have on the measuring characteristics of the apparatus, the wire or film are shaped so that their leading edge constitutes an area much smaller than the surfaces which are substantially parallel to the stream lines.

Abstract: A flow rate measuring device, especially for measuring the flow rate of incoming fresh air in the induction tube of an internal combustion engine in which a temperature-dependent sensor, e.g. a resistor, is exposed to the air flow while the current through the sensor is controlled and monitored to obtain a signal related to the air flow rate. In order to prevent damage to the sensor from high-temperature flame fronts due to backfiring and also from inadvertent mechanical contact with tools, etc., there is provided at least one protective element downstream of the sensor and possibly another element upstream. The protective element is a plate-like barrier permitting essentially unimpeded air flow. The pattern of the element may be a grid or sieve, a honeycomb pattern or a plurality of parallel tubes.

Abstract: Circuitry is described for use with a fuel mixture control system of an internal combustion engine in which an oxygen sensor is located in the exhaust system and generates a generally bi-valued signal which is compared with a set-point voltage to indicate rich or lean mixtures. In order to permit control loop operation even when the sensor signal changes due to decreasing temperatures, the set point voltage is adjusted to remain between the two values of the sensor signal. This adjustment is effective only when the lower sensor signal exceeds a given limit.

Abstract: A circuit to be used in association with a fuel mixture control system which includes an oxygen sensor in the exhaust system to determine the relative richness of the combustible mixture. When the engine operates at low speeds, its control response time becomes large due to decreased engine throughput. In order to prevent control oscillations from occcurring under these conditions, the time constant of integration of the oxygen sensor control loop is changed to accommodate to the longer engine response time. For this purpose, the zero crossings of the oxygen sensor signal are compared with the unstable time constant of a multivibrator and a transistor which normally shunts a timing resistor is blocked, thereby increasing the time constant of the control integrator.

Abstract: A fuel injection system for an internal combustion engine includes electromagnetic injection valves controlled by a fuel control unit which receives signals from a camshaft actuated switch, a position-dependent throttle transducer and an oxygen sensor. When the oxygen sensor changes output levels, the transmission of this information is delayed, by the action of a switching transistor controlled by a monostable multivibrator, for a period of time equal to the internal time constant of the multivibrator.

Abstract: The maximum speed of an internal combustion engine is limited by a device which compares the period of rpm-synchronous pulses with the time constant of a reference multivibrator. If the engine rpm is so high that a pulse terminates prior to expiration of the reference time period, a gate is activated and acts through further multivibrator circuits to interrupt the fuel delivery to the engine, e.g., the fuel injection control pulses are suppressed. If the maximum rpm is exceeded only intermittently, the device restores normal fuel injection control pulses after a predetermined number of pulses has been suppressed. If the maximum rpm is exceeded continuously, the device restores normal fuel control somewhat later than the time at which the engine speed drops to below maximum rpm.

Abstract: A fuel injection system for an internal combustion engine includes electromagnetic injection valves controlled by a fuel control unit which receives signals from a camshaft actuated switch, a position-dependent throttle transducer and an oxygen sensor. When the oxygen sensor changes output levels, the transmission of this information is delayed, by the action of a switching transistor controlled by a monostable multivibrator, for a period of time equal to the internal time constant of the multivibrator.