Abstract: A method of controlling a brushless motor that includes sensing a temperature and using the sensed temperature to define a current limit. A lower current limit is then defined for a lower sensed temperature. A winding of the motor is sequentially energized and de-energized, with the winding being de-energized when current in the winding exceeds the defined current limit.

Abstract: A surface cleaning appliance having a cleaner head that includes an agitator and a motor for driving the agitator. The appliance includes a switch coupling the motor to a supply voltage, a voltage sensor for measuring the magnitude of the supply voltage, a current sensor for measuring the magnitude of current through the motor, and a controller configured to output a PWM signal for controlling the switch. The controller then adjusts the duty cycle of the PWM signal in response to changes in the supply voltage and in response to changes in the current through the motor.

Abstract: A motor driving apparatus for a cleaning appliance includes a battery source and a power controller. The battery source supplies the power controller with an output having a first voltage which decreases as the battery source is discharged. The power controller modulates the output to produce a drive signal for driving a motor that has a second voltage and a variable duty cycle. The power controller increases the duty cycle of the drive signal as the first voltage decreases in order to maintain the second voltage at a substantially constant average value per unit time. By providing the above arrangement, the motor can be supplied with a constant voltage throughout the available run time of the battery. When forming part of a cleaning appliance having a motor, the above arrangement allows the motor to operate at a substantially constant speed throughout the run time of the battery.

Abstract: A surface cleaning appliance having a cleaner head that includes an agitator and a motor for driving the agitator. The appliance includes a switch coupling the motor to a supply voltage, a voltage sensor for measuring the magnitude of the supply voltage, a current sensor for measuring the magnitude of current through the motor, and a controller configured to output a PWM signal for controlling the switch. The controller then adjusts the duty cycle of the PWM signal in response to changes in the supply voltage and in response to changes in the current through the motor.

Abstract: A method of controlling a brushless motor that includes sensing a temperature and using the sensed temperature to define a current limit. A lower current limit is then defined for a lower sensed temperature. A winding of the motor is sequentially energised and de-energised, with the winding being de-energised when current in the winding exceeds the defined current limit.

Abstract: A controller for a brushless motor that includes a processor, a first timer, a second timer, a compare register, a comparator, an input, and one or more outputs. The processor starts the first timer in response to a signal at the input. The first timer then generates an interrupt after a first period. In response to the interrupt, the processor generates a first control signal at the outputs. The processor also loads the compare register and starts the second timer in response to either the input signal or the interrupt. The comparator then generates a second control signal at the outputs when the second timer and the compare register correspond. Additionally, a motor system that includes the controller.

Abstract: A controller for a brushless motor that includes a processor, a first timer, a second timer, a compare register, a comparator, an input, and one or more outputs. The processor starts the first timer in response to a signal at the input. The first timer then generates an interrupt after a first period. In response to the interrupt, the processor generates a first control signal at the outputs. The processor also loads the compare register and starts the second timer in response to either the input signal or the interrupt. The comparator then generates a second control signal at the outputs when the second timer and the compare register correspond. Additionally, a motor system that includes the controller.

Abstract: It is disclosed a method and a device for measurement of a flow in an object, especially a lumen or a vessel, comprising: generating a temporal sequence of images of the object; determining reliability maps, whereas a reliability map corresponds to an image of the object. Another exemplary embodiment is a method and a device for calculating flow parameters (13), comprising: comparing (15) of a predicted image of a flow (16) with an image of a flow (17) with respect to a reliability map (18) of an image of the flow; and adaptation (12) of the predicted flow (16) with respect to the result of the comparing (15). Furthermore, it is described a computer program having instructions recorded thereon in order to execute one of the above-mentioned methods.

Abstract: A motor driving apparatus for a cleaning appliance includes a battery source and a power controller. The battery source supplies the power controller with an output having a first voltage which decreases as the battery source is discharged. The power controller modulates the output to produce a drive signal for driving a motor that has a second voltage and a variable duty cycle. The power controller increases the duty cycle of the drive signal as the first voltage decreases in order to maintain the second voltage at a substantially constant average value per unit time. By providing the above arrangement, the motor can be supplied with a constant voltage throughout the available run time of the battery. When forming part of a cleaning appliance having a motor, the above arrangement allows the motor to operate at a substantially constant speed throughout the run time of the battery.