Abstract: A hand-guided motorized working apparatus and an operating device for the apparatus are provided. The operating device has a handle shank configured to be hand-gripped, an operating element receiving region adjoining the handle shank, and an operating unit which acts on the apparatus operation and includes an operating element which is held movably on the operating element receiving region for actuation by a finger of a hand gripping the handle shank, and has a finger rest region extending along an outer side of the operating element receiving region.

Abstract: An arrangement of a housing and a guide tube is provided wherein one end of the guide tube is held in the housing. The position of the guide tube is adjustable relative to the housing in the direction of the longitudinal center axis of the guide tube. A rotation stop stops swiveling of the guide tube relative to the housing and includes a guide part. The guide part is mounted in one of the guide tube and housing. A longitudinal wall runs in the direction of the axis on the other one of the guide tube and housing. The longitudinal wall interacts with the guide part during swiveling of the guide tube about its axis. The guide part is tiltable relative to the guide tube about a tilt axis. The tilt axis runs along the guide tube and at a distance (a, b) from the axis of the guide tube.

Abstract: A hand-guided garden, forestry and/or construction working apparatus has an inactive state, an active state and a variable setting, as well as an apparatus operator control element which can be activated by a user. In the inactive state, the garden, forestry and/or construction working apparatus is designed to be transferred into the active state triggered by activation of the apparatus operator control element, and in the active state the garden, forestry and/or construction working apparatus is designed to change the setting and not to be transferred into the inactive state triggered by activation of the apparatus operator control element.

Abstract: A hand-guided motorized working apparatus and an operating device for the apparatus are provided. The operating device has a handle shank configured to be hand-gripped, an operating element receiving region adjoining the handle shank, and an operating unit which acts on the apparatus operation and includes an operating element which is held movably on the operating element receiving region for actuation by a finger of a hand gripping the handle shank, and has a finger rest region extending along an outer side of the operating element receiving region.

Abstract: An arrangement of a housing and a guide tube is provided wherein one end of the guide tube is held in the housing. The position of the guide tube is adjustable relative to the housing in the direction of the longitudinal center axis of the guide tube. A rotation stop stops swiveling of the guide tube relative to the housing and includes a guide part. The guide part is mounted in one of the guide tube and housing. A longitudinal wall runs in the direction of the axis on the other one of the guide tube and housing. The longitudinal wall interacts with the guide part during swiveling of the guide tube about its axis. The guide part is tiltable relative to the guide tube about a tilt axis. The tilt axis runs along the guide tube and at a distance (a, b) from the axis of the guide tube.

Abstract: A handheld work apparatus has an electric drive motor (24) and a power supply unit for the drive motor (24). The power supply unit is arranged in a receptacle (7) of a housing (2) of the work apparatus. The work apparatus has an electronic control (17) and a blower wheel (29) for conveying cooling air. The blower wheel (29) is driven by a drive motor (24). The housing (2) has at least one air inlet opening (10) for cooling air via which the blower wheel (29) draws in a first cooling air flow (22) during operation. A second cooling air flow (23) is drawn into the housing (2) via the receptacle (7).

Abstract: A handheld work apparatus has an electric drive motor (24) and a power supply unit for the drive motor (24). The power supply unit is arranged in a receptacle (7) of a housing (2) of the work apparatus. The work apparatus has an electronic control (17) and a blower wheel (29) for conveying cooling air. The blower wheel (29) is driven by a drive motor (24). The housing (2) has at least one air inlet opening (10) for cooling air via which the blower wheel (29) draws in a first cooling air flow (22) during operation. A second cooling air flow (23) is drawn into the housing (2) via the receptacle (7).

Abstract: In a method for monitoring the functionality of a temperature sensor that can deliver an electrical signal as a function of the measured temperature and is disposed, in particular, in the cooling water circuit of an internal combustion engine, the persistence of the temperature sensor in the high signal range is made possible by a method encompassing the following steps: Characterizing the sensor as possibly faulty if the sensor indicates, upon engine shutdown, at least a maximum value of the cooling fluid temperature; determining a first gradient of the cooling fluid temperature, measured by the possibly faulty sensor, up to a first point in time after engine shutdown, and characterizing the sensor as fault-free if the gradient exceeds a minimum value; determining a second gradient of the cooling fluid temperature, measured by the possibly faulty sensor, between the point in time and a point in time after engine shutdown, and characterizing the sensor as fault-free if the second gradient exceeds a minimum va

Abstract: A method for monitoring motor vehicle systems that include mechanical components and at least one control device detects, in a first step, input signals and output signals as quantitative signals that characterize the operating behavior, assigns discrete qualitative values to value intervals of the input signals and output signals, which are established using a particular sequence of threshold values. A change to one of the qualitative values is recognized as an event, and consecutive events are stored as an event sequence. The event sequence is compared with a model of the normal behavior of the motor vehicle system, in particular a model composed of all event sequences of the proper operation of the motor vehicle system. If there is a match, it is assumed that the motor vehicle system is operating properly. If there is no match, erroneous operation is assumed.

Abstract: In a method for monitoring the functionality of a temperature sensor that can deliver an electrical signal as a function of the measured temperature and is disposed, in particular, in the cooling water circuit of an internal combustion engine, the persistence of the temperature sensor in the high signal range is made possible by a method encompassing the following steps: Characterizing the sensor as possibly faulty if the sensor indicates, upon engine shutdown, at least a maximum value of the cooling fluid temperature; determining a first gradient of the cooling fluid temperature, measured by the possibly faulty sensor, up to a first point in time after engine shutdown, and characterizing the sensor as fault-free if the gradient exceeds a minimum value; determining a second gradient of the cooling fluid temperature, measured by the possibly faulty sensor, between the point in time and a point in time after engine shutdown, and characterizing the sensor as fault-free if the second gradient exceeds a minimum va

Abstract: With devices and methods for reducing the contamination of a sensor, a sensor or sensor element—preferably a hot film air-mass meter—is deactivated when a software function integrated in the electronic control unit detects a possible contamination or a media carry-in. The sensor is deactivated using a high-side switch in the voltage supply or a low-side switch in the ground connection, wherein the media carry-in detection and the switch control are carried out by the control unit or an evaluation unit in the sensor. After the sensor is deactivated, a substitute signal is optionally generated that replaces the missing output signal of the sensor.

Abstract: The invention relates to devices and methods for reducing the contamination of a sensor with which a sensor or sensor element—preferably a hot film air-mass meter—is deactivated when a software function integrated in the electronic control unit detects a possible contamination or a media carry-in. The sensor is deactivated using a high-side switch in the voltage supply or a low-side switch in the ground connection, wherein the media carry-in detection and the switch control are carried out by the control unit or an evaluation unit in the sensor. After the sensor is deactivated, a substitute signal is optionally generated that replaces the missing output signal of the sensor.

Abstract: A method for monitoring a microprocessor and a circuit arrangement having a microprocessor are described. A microprocessor is monitored using an assigned watchdog. The watchdog monitors whether reset pulses are received within a time interval of predetermined duration. If the reset pulse is received, the time interval is reset and restarted. If reset pulses are not received, a reset of the microprocessor is initiated. In suitable operating phases of the microprocessor, a check function of the watchdog is activated. During the execution of the check function, first a reset of the watchdog is executed and then a sequence of waiting loops, whose duration is greater than the duration of the time interval of the watchdog, is executed.

Abstract: A method for checking at least three sensors which detect a measured quantity in the area of an internal combustion engine. A measure of the sensor signal of the particular sensor to be checked is compared to a reference signal which is obtained from at least one part of the sensor signals of the sensors to be checked. A sensor is recognized as defective on the basis of a comparison of the measure for the sensor signal with the reference signal. The reference signal is formed, for example, from a mean value of a measure of the sensor signals of at least one part of the sensors to be checked, the individual sensor signals being weighted using correction factors in forming the mean value. The sensors are temperature sensors or pressure sensors, for example, which may be situated in an intake area of the internal combustion engine, on the internal combustion engine itself, in an exhaust area, and/or in an exhaust gas treatment system.

Abstract: Provided are a method and device for operating an internal combustion engine having exhaust-gas recirculation, the method and device allowing a diagnosis of an exhaust-gas recirculation cooler during normal operation of the internal combustion engine. In this context, a variable characteristic of the functioning of the exhaust-gas recirculation cooler is monitored. The variable characteristic of the functioning of the cooling device is ascertained as a function of a measured value. The variable characteristic of the functioning of the exhaust-gas recirculation cooler is specified on the basis of an intact exhaust-gas recirculation cooler. The ascertained value of the variable characteristic of the functioning of the exhaust-gas recirculation cooler is compared to the predefined value. An error is detected when the ascertained value of the variable characteristic of the function of cooling device deviates from the specified value.

Abstract: A method and device for determining a vectorial vehicle velocity by estimating a mean value for the vehicle velocity by using a position-finding device to obtain a first value, and to then compare this first value with a second value estimated using inertial sensors.

Abstract: A method for checking at least three sensors which detect a measured quantity in the area of an internal combustion engine. A measure of the sensor signal of the particular sensor to be checked is compared to a reference signal which is obtained from at least one part of the sensor signals of the sensors to be checked. A sensor is recognized as defective on the basis of a comparison of the measure for the sensor signal with the reference signal. The reference signal is formed, for example, from a mean value of a measure of the sensor signals of at least one part of the sensors to be checked, the individual sensor signals being weighted using correction factors in forming the mean value. The sensors are temperature sensors or pressure sensors, for example, which may be situated in an intake area of the internal combustion engine, on the internal combustion engine itself, in an exhaust area, and/or in an exhaust gas treatment system.

Abstract: Provided are a method and device for operating an internal combustion engine having exhaust-gas recirculation, the method and device allowing a diagnosis of an exhaust-gas recirculation cooler during normal operation of the internal combustion engine. In this context, a variable characteristic of the functioning of the exhaust-gas recirculation cooler is monitored. The variable characteristic of the functioning of the cooling device is ascertained as a function of a measured value. The variable characteristic of the functioning of the exhaust-gas recirculation cooler is specified on the basis of an intact exhaust-gas recirculation cooler. The ascertained value of the variable characteristic of the functioning of the exhaust-gas recirculation cooler is compared to the predefined value. An error is detected when the ascertained value of the variable characteristic of the function of cooling device deviates from the specified value.

Abstract: The invention is directed to a method and an arrangement for operating an internal combustion engine assembly (1) which make possible a monitoring and, if required, correction of a quantity of an air system of the engine assembly (1). A physical quantity of the air system is computed from several input quantities with the aid of a physical model (5) of the air system of the internal combustion engine assembly (1). The at least one physical quantity is not an input quantity of the physical model (5). The at least one physical quantity, which is computed by means of the physical model (5), is compared to a measured value for the at least one physical quantity. One of the input quantities or a model internal quantity of the physical model (5) is monitored in dependence upon a deviation between the computed value and the measured value for the at least one physical quantity.

Abstract: A method for monitoring motor vehicle systems that include mechanical components and at least one control device detects, in a first step, input signals and output signals as quantitative signals that characterize the operating behavior, assigns discrete qualitative values to value intervals of the input signals and output signals, which are established using a particular sequence of threshold values. A change to one of the qualitative values is recognized as an event, and consecutive events are stored as an event sequence. The event sequence is compared with a model of the normal behavior of the motor vehicle system, in particular a model composed of all event sequences of the proper operation of the motor vehicle system. If there is a match, it is assumed that the motor vehicle system is operating properly. If there is no match, erroneous operation is assumed.