Abstract: A valve without position indicating switches. Positions of the valve are detected from current magnitude measurements and current profile analytics. The current profile may be learned initially and relearned and adapted at each operation. The valve may be opened and closed by a driver that is actuated by an electrical current to control the opening and closing of the valve. The current may be regulated by a controller to open and close the valve appropriately.

Abstract: A device dewaters a wet-laid non-woven web formed from a fibrous suspension. The device has a multiplicity of dewatering strips which are disposed so as to be mutually spaced apart. Mutually neighboring dewatering strips conjointly delimit a dewatering gap for discharging liquid from the fibrous suspensions. The device further has at least three format slides which along the longitudinal direction of the respective dewatering gap are disposed or disposable so as to be distributed relative to one another and which partially obscure the dewatering gap in such a manner that any discharging of the liquid by way of the obscured part of the dewatering gap is prevented.

Abstract: A circuit that indicates a warning of low battery life so that an instrument supported by a battery, may have the battery replaced before the battery dies. A switch and series resistor may be connected between the battery and a capacitor. The switch may turn on when the voltage on the capacitor is below a first predetermined voltage limit, and the switch may be turned off when the voltage at the capacitor is above a second predetermined voltage limit. When the switch is on, a voltage on the resistor can be measured and current consumption can be calculated with measured voltage, resistor value and duty cycle of the switch. When the battery is discharged, its internal resistance and then its duty cycle may increase. When the duty cycle hits 100 percent, the battery may be nearly dead but with enough life for the circuit to issue the low battery warning.

Abstract: A circuit that indicates a warning of low battery life so that an instrument supported by a battery, may have the battery replaced before the battery dies. A switch and series resistor may be connected between the battery and a capacitor. The switch may turn on when the voltage on the capacitor is below a first predetermined voltage limit, and the switch may be turned off when the voltage at the capacitor is above a second predetermined voltage limit. When the switch is on, a voltage on the resistor can be measured and current consumption can be calculated with measured voltage, resistor value and duty cycle of the switch. When the battery is discharged, its internal resistance and then its duty cycle may increase. When the duty cycle hits 100 percent, the battery may be nearly dead but with enough life for the circuit to issue the low battery warning.

Abstract: A device dewaters a wet-laid non-woven web formed from a fibrous suspension. The device has a multiplicity of dewatering strips which are disposed so as to be mutually spaced apart. Mutually neighboring dewatering strips conjointly delimit a dewatering gap for discharging liquid from the fibrous suspensions. The device further has at least three format slides which along the longitudinal direction of the respective dewatering gap are disposed or disposable so as to be distributed relative to one another and which partially obscure the dewatering gap in such a manner that any discharging of the liquid by way of the obscured part of the dewatering gap is prevented.

Abstract: A method of manufacturing a wet-laid nonwoven web includes the following steps: feeding a pulp suspension onto a forming screen for depositing a fibrous web thereon, wherein the pulp suspension has industrially produced, inorganic fibers or fibers of synthetically produced polymers and the pulp suspension is substantially free from binders, such as chemical binders, and hydraulic consolidation of the fibrous web to generate the nonwoven web through water jet needling of the fibrous web.

Abstract: Defining a human resource system is disclosed. Metadata models are defined. Processes are defined. The human resources system is stored including metadata models and processes, wherein the stored metadata models and processes are interpreted using an interpretive engine, wherein the interpretive engine is configured to process the metadata model and process definitions without compilation of any code, and wherein defining metadata models and defining processes when interpreted by the interpretive engine is sufficient to define a fully functional human resource system.

Abstract: A power converter circuit includes a transformer and a main switch controller by a primary side controller. A sensing circuit is implemented that senses the voltage at an auxiliary winding of the transformer while the main switch is ON. The auxiliary winding is another winding on the primary side of the transformer, magnetically coupled to the secondary winding and electrically isolated from the primary winding. When the voltage across the auxiliary winding reaches a predefined threshold voltage level, the main switch is switched OFF. The threshold voltage level is set at a value that minimizes an amount of energy transferred per pulse to the secondary side of the circuit while maintaining a minimum amount of energy transfer to enable output voltage sensing at the auxiliary winding.

Abstract: A controller for a power converter and method of operating the same. In one embodiment, the controller includes a peak detector, coupled to a circuit element of the power converter, configured to produce a signal corresponding to a peak current through a circuit element. The controller also includes an adjustable reference circuit responsive to a difference between the signal and a reference signal corresponding to a desired peak current to produce a corrected signal corresponding to the peak current.

Abstract: A pulse scheme is used for load change detection in a switching mode power supply with low no-load power consumption. The pulse scheme includes a measurement pulse for determining a load condition or a no-load condition at the output. Generation of the measurement pulse results in sufficient energy transfer to the secondary side to accurately measure the output voltage via a reflected voltage on the primary side. Once in no-load operation mode, a reference pulse having a lower energy transfer than the measurement pulse is used to determine a baseline reflected voltage value that corresponds to a no-load condition. Successive detection pulses are then generated and corresponding reflected voltage measured and compared to the baseline reflected voltage. A change in the reflected value that exceeds a threshold value is indicative of a change in the no-load condition.

Abstract: A startup circuit with reduced power dissipation, method of operating the same and a power converter employing the startup circuit. In one embodiment, the startup circuit for a controller includes a charge accumulation circuit having a resistor series-coupled to a capacitor and a first Schmitt trigger having an input coupled to the capacitor. The startup circuit also includes a second Schmitt trigger having an input coupled to an output of the first Schmitt trigger and configured to provide a bias voltage for the controller via the capacitor when an input voltage thereto exceeds a trip voltage.

Abstract: A control system for a power converter with reduced power dissipation and method of operating the same. In one embodiment, the control system includes a first controller coupled to a primary winding of a transformer and configured to control a duty cycle of a power switch to regulate an output characteristic of the power converter. The control system also includes a second controller configured to provide a signal to one of a secondary winding of the transformer and a circuit element spanning an isolation boundary of the transformer in response to a dynamic change of the output characteristic to trigger the first controller to initiate the duty cycle for the power switch.

Abstract: A controller for a switch and a method of operating the same. In one embodiment, the controller is configured to measure a voltage of a control terminal of the switch and select a first mode of operation if the voltage of the control terminal is greater than a threshold voltage, and a second mode of operation if the voltage of the control terminal is less than the threshold voltage.

Abstract: A controller for a power converter and method of operating the same. In one embodiment, the controller includes a primary peak current circuit configured to produce a reference voltage corresponding to a primary peak current through a primary winding of a transformer of a power converter, and an offset corrector configured to provide an offset voltage to compensate for delays in the power converter. The controller also includes a summer configured to provide an offset reference voltage as a function of the reference voltage and the offset voltage, and a comparator configured to produce a signal to turn off a power switch coupled to the primary winding of the transformer as a function of the offset reference voltage.

Abstract: A controller for a switch and a method of operating the same. In one embodiment, the controller is configured to measure a voltage of a control terminal of the switch and select a first mode of operation if the voltage of the control terminal is greater than a threshold voltage, and a second mode of operation if the voltage of the control terminal is less than the threshold voltage.

Abstract: A driver for a switch, method of driving a switch, and a power converter employing the same. The driver for the switch includes a first driver switch coupled to a terminal of the switch. The driver also includes a second driver switch inverted with respect to the first driver switch and coupled to another terminal of the switch, wherein the first and second driver switches are configured to provide a drive signal to a control terminal of the switch.

Abstract: A control system for a power converter with reduced power dissipation at light loads and method of operating the same. In one embodiment, the control system includes a first controller configured to control a duty cycle of a power switch to regulate an output characteristic of the power converter. The control system also includes a second controller configured to provide a signal in response to a dynamic change of the output characteristic to the first controller to initiate the duty cycle for the power switch.

Abstract: A control circuit for a primary controlled switched-mode power supply that has a primary-side switch and a transmitter. It also relates to an associated switched-mode power supply. The control circuit can be connected to a control input of the primary-side switch so that the primary-side switch is controlled based on a secondary-side current flow time period in which a current flows through the secondary-side winding of the transmitter in order to regulate the output voltage. The secondary-side current flow time period can be used as a control parameter instead of the actual output voltage in order to then control the primary-side switch. Because the secondary-side current flow time period can be determined indirectly on the primary side, no direct feedback is necessary between the output voltage on the secondary side and the control circuit on the primary side.

Abstract: A controller for a power converter and method of operating the same. In one embodiment, the controller includes a peak detector, coupled to a circuit element of the power converter, configured to produce a signal corresponding to a peak current through a circuit element. The controller also includes an adjustable reference circuit responsive to a difference between the signal and a reference signal corresponding to a desired peak current to produce a corrected signal corresponding to the peak current.

Abstract: A controller for a power converter and method of operating the same. In one embodiment, the controller includes a primary peak current circuit configured to produce a reference voltage corresponding to a primary peak current through a primary winding of a transformer of a power converter, and an offset corrector configured to provide an offset voltage to compensate for delays in the power converter. The controller also includes a summer configured to provide an offset reference voltage as a function of the reference voltage and the offset voltage, and a comparator configured to produce a signal to turn off a power switch coupled to the primary winding of the transformer as a function of the offset reference voltage.