Abstract: A hand-guided work apparatus includes a combustion engine to drive a work tool. The combustion engine includes a crankcase (14) in which a crankshaft (16) is rotatably mounted about a rotational axis (44). A pressure sensor (27) and a temperature sensor (26) are arranged on the crankcase (14). The pressure sensor (27) and the temperature sensor (26) are arranged in a common sensor housing (31). In the typical put-down position (8) of the work apparatus, the pressure sensor (27) and the temperature sensor (26) are arranged below a plane (45) which is parallel to the horizontal storage surface (7) and contains the rotational axis (44) of the crankshaft (16). A connecting channel (25) is formed in the sensor housing (31). The connecting channel (25) connects the pressure sensor (27) to the crankcase interior (20) and the base (35) of the connecting channel (25) slopes down toward the crankcase interior (20) in the typical put-down position (8) of the work apparatus.

Abstract: It is referred to a flow control arrangement and a method for controlling the flow of a fluid. Given that the sensor device supports measurements for determining an average flow of a fluid, a sensor signal of a flow sensor of the sensor device is first linearized and subsequently processed, and supplied as actual flow to a controller for controlling an ON/OFF valve. The linearized signal values are provided at a rate not less than a maximum switching frequency of the ON/OFF valve. This allows for detecting oscillations resulting from a high frequent switching of the valve.

Abstract: The flow sensor comprises a heater arranged between two sensing thermopiles. In addition, at least one monitoring thermocouple is provided for measuring the temperature of the heater. The signal from the monitoring thermocouple can be used to improve the accuracy of the device in several ways. In particular, the signal from the monitoring thermocouple depends on changes of the Seeback constant and other inherent properties of the thermopiles in the same way as the signal from the sensing thermopiles, which allows a compensation of such effects. The signal from the monitoring thermocouple can also be used as a reference voltage to an A/D converter for converting the signals from the sensing thermopiles.

Abstract: A semiconductor wafer (10) is structured such that fine structures (3), such as membranes, bridges or tongues, with a thickness d<<D are formed, wherein D designates the thickness of the semiconductor wafer (10). Then particles of a desired material are applied. A temporal or spatial temperature gradient is generated in the semiconductor wafer (10), e.g. by progressive heating. In such a heating process the fine structures heat up more quickly and become hotter than the remaining wafer because they have a smaller heat capacity per area and cannot carry off heat as quickly. In this manner, the fine structures can be heated to a temperature that allows a sintering of the particles. For coating the semiconductor wafer (10) is brought into a reactor (11). A precursor compound of a metal is provided and fed to the reactor (11), where a reaction takes place during which the metal is transformed to a final compound and is deposited in the form of particles on the semiconductor wafer (10).

Abstract: A semiconductor wafer (10) is structured such that fine structures (3), such as membranes, bridges or tongues, with a thickness d<<D are formed, wherein D designates the thickness of the semiconductor wafer (10). Then particles of a desired material are applied. A temporal or spatial temperature gradient is generated in the semiconductor wafer (10), e.g. by progressive heating. In such a heating process the fine structures heat up more quickly and become hotter than the remaining wafer because they have a smaller heat capacity per area and cannot carry off heat as quickly. In this manner, the fine structures can be heated to a temperature that allows a sintering of the particles. For coating the semiconductor wafer (10) is brought into a reactor (11). A precursor compound of a metal is provided and fed to the reactor (11), where a reaction takes place during which the metal is transformed to a final compound and is deposited in the form of particles on the semiconductor wafer (10).

Abstract: A method and device are disclosed for calibrating sensors, which sensors are arranged on semiconductor chips and are e.g. to be used for detecting a substance in a fluid. The sensors are calibrated while they are still assembled on a semiconductor wafer by exposing the wafer to a calibration fluid containing a known amount of the substance to be measured. Hence, rather than first cutting the wafer, the sensors are calibrated at an early stage. For this purpose, they are placed on a chuck below a lid. The calibration fluid with known parameters is introduced between the wafer and the lid. This allows to test and calibrate a large number of sensors quickly.

Abstract: To process a plurality of sensor devices, such as humidity sensors or gas sensors, the sensor devices are run through a testing station and a turret handler. In order to increase throughput of the testing station, several test cycles are operated simultaneously in a phase-shifted manner. The sensor devices are e.g. sequentially fed onto trays of the test station, on which they are assembled in batches. Each batch is subjected to a test cycle. After the test cycle, the sensor devices of a batch are sequentially fed back to the turret handler.

Abstract: The flow sensor or other type of sensor comprises a package having a cylindrical section arranged between an anchor section and a head section. The diameter of the anchor section is typically larger than the diameter of the cylindrical section, which in turn is typically larger than the diameter of the head section. A sensor chip is embedded partially into the package, with a sensitive area being exposed to the surroundings. The sensor can e.g. be inserted into a bore having a diameter matching the one of the cylindrical section.

Abstract: The humidity detector comprises a housing adapted to hold a humidity sensor towards the windscreen of a vehicle or any other type of window. A flexible printed circuit board is arranged between the humidity sensor and the windscreen and provides a connection between the humidity sensor and further circuitry of the detector. The humidity sensor is located under a cap, which is engaged by a glider member. A spring pushes the glider member towards the windscreen.

Abstract: A flow detector has a housing (1) with tongues (8), which allow to anchor it to a support to withstand pulling forces. The housing further comprises pegs (41) provided to mate with openings or recesses in the same support, which allow to secure it against lateral forces. The tongues (8) and pegs (41) are mounted to a hull (7) of a housing (1) of the detector, which carries on its opposite side an inlet (4a) and an outlet (4b) for the fluid to be measured. Connectors (5) are provided on the same side as the tongues (8) and the pegs (41) for connecting the detector to an external system. This design is robust and allows to mount the detector to the support in quick and secure manner.

Abstract: A system for storing ammonia comprises gas detector that is able to detect gases other than ammonia. The system further comprises thermally activatable ammonia stores, which can be activated to release ammonia upon heating. When the ammonia stores are not heated, the system is below ambient pressure and any leak will cause external gas to enter the system. Therefore, the gas detector is used to detect the presence of such external gas, which allows to detect leaks. The gas detector may be embodied as a thermal detector using a single heater and two temperature sensors for detecting a gas flow as well as external gas.

Abstract: A flow sensor is equipped with a non-volatile memory for storing various information, such as a count of thermal and/or chemical treatments for sterilization that the sensor has been subjected to, a serial number, an expiry date, or notifications. When connecting the flow sensor to a control unit, this data is read out and processed appropriately. For example, after each treatment, the count of thermal treatments stored in memory is increased, or the expiry date is checked against the current date.

Abstract: A pressure sensor is manufactured by joining two wafers, the first wafer comprising CMOS circuitry and the second being an SOI wafer. A recess is formed in the top material layer of the first wafer, which is covered by the silicon layer of the second wafer to form a cavity. Part or all of the substrate of the second wafer is removed to forming a membrane from the silicon layer. Alternatively, the cavity can be formed in the second wafer. The second wafer is electrically connected to the circuitry on the first wafer. This design allows to use standard CMOS processes for integrating circuitry on the first wafer.

Abstract: The flow of a fluid of unknown composition is measured by leading the fluid over a first temperature sensor, a heater and a second temperature sensor. The temperature difference DTP between the temperature sensors is measured, as well as the temperature T of at least one of them. In addition, calibration data is used to store the temperature Tref of a known reference fluid. The offset T?Tref at a given temperature difference DTP is a direct measure of the composition of the fluid and allows to retrieve any parameter depending on the same.

Abstract: A differential pressure sensor comprises a membrane arranged over a cavity on a semiconductor substrate. A lid layer is arranged at the top side of the device and comprises an access opening for providing access to the top side of the membrane. A channel extends laterally from the cavity and intersects with a bore. The bore is formed by laser drilling from the bottom side of the substrate and provides access to the bottom side of the membrane. The bore extends all through the substrate and optionally into the lid layer.

Abstract: A thermal flow sensor is equipped with a self-test unit that monitors the device and generates a fault signal in the presence of a malfunction. The self-test unit can e.g. monitor the integrity of a membrane carrying the heater and temperature sensors, or it can monitor various operational parameters of the device, thereby increasing the safety of the device.

Abstract: A flow detector has a housing (1) with tongues (8), which allow to anchor it to a support to withstand pulling forces. The housing further comprises pegs (41) provided to mate with openings or recesses in the same support, which allow to secure it against lateral forces. The tongues (8) and pegs (41) are mounted to a hull (7) of a housing (1) of the detector, which carries on its opposite side an inlet (4a) and an outlet (4b) for the fluid to be measured. Connectors (5) are provided on the same side as the tongues (8) and the pegs (41) for connecting the detector to an external system. This design is robust and allows to mount the detector to the support in quick and secure manner.

Abstract: A semiconductor wafer (10) is structured such that fine structures (3), such as membranes, bridges or tongues, with a thickness d<<D are formed, wherein D designates the thickness of the semiconductor wafer (10). Then particles of a desired material are applied. A temporal or spatial temperature gradient is generated in the semiconductor wafer (10), e.g. by progressive heating. In such a heating process the fine structures heat up more quickly and become hotter than the remaining wafer because they have a smaller heat capacity per area and cannot carry off heat as quickly. In this manner, the fine structures can be heated to a temperature that allows a sintering of the particles. For coating the semiconductor wafer (10) is brought into a reactor (11). A precursor compound of a metal is provided and fed to the reactor (11), where a reaction takes place during which the metal is transformed to a final compound and is deposited in the form of particles on the semiconductor wafer (10).

Abstract: The flow sensor comprises a heater arranged between two sensing thermopiles. In addition, at least one monitoring thermocouple is provided for measuring the temperature of the heater. The signal from the monitoring thermocouple is used as a reference voltage for an A/D converter, which converts the signals from the sensing thermopiles. This allows to increase the resolution of the converter at higher flows, which results in more accurate measurements.

Abstract: A thermal flow sensor is equipped with a self-test unit that monitors the device and generates a fault signal in the presence of a malfunction. The self-test unit can e.g. monitor the integrity of a membrane carrying the heater and temperature sensors, or it can monitor various operational parameters of the device, thereby increasing the safety of the device.