Abstract:
: A surgical stapler. The surgical stapler includes a drive system, an electric motor, a battery and a control system. The electric motor is mechanically coupled to the drive system. The battery is electrically couplable to the electric motor. The control system is electrically connected to the electric motor and includes an H-bridge circuit, an electrically resistive element and an electrically inductive element. The H-bridge circuit includes a high side and a low side. The low side of the H-bridge circuit includes first and second switching devices. The electrically resistive element is electrically connected in series with the first switching device. The electrically inductive element is electrically connected to the electrically resistive element. The control system is configured to control a force applied to the drive system based on a current downstream of the electrically resistive element.
Abstract:
A drive mechanism (16A, 16B) configured to drive a thermally isolated actuator (30) between two positions. The drive mechanism includes a rotary actuated motor (18) configured to rotatably drive a motor member (20), and a drive member (22) coupled to the motor member and having a drive arm (24, 42) configured to responsively move from a first position to a second position upon rotation of the motor member. An actuator (30) is responsive to movement of the drive arm (24) moved from the first position to the second position. A drive circuit (60) is configured to generate a pulse width modulated (PWM) drive signal (70) configured to controllably drive the motor, the PWM drive signal having a first duty cycle (Phase 1) configured to advance the drive arm from the first position, and having a second duty cycle (Phase 2) different than the first duty cycle as the drive arm approaches the second position. The drive signal may be removed (Phase3) before the drive arm (42) engages a hard stop (54). The drive mechanism may comprise at least one sensor (40) configured to determine a position of the drive arm (42) proximate the first position and proximate the second position. The actuator is thermally isolated from the drive arm (42) in both the first position and the second position.
Abstract:
An electric power tool comprising a voltage conversion circuit configured to control magnitude of a voltage applied to a motor in accordance with magnitude of load.
Abstract:
A system may regulate voltage supplied from a power source to an integrated circuit and/or an inertial device. A minimal voltage may be maintained in the integrated circuit by temporarily cutting off current to the inertial device to supply surges of voltage to the controller. Optionally voltage may be smoothed between said surges for example by adding capacitance and/or a current restrictor.
Abstract:
An electric working machine including: a motor; a driving unit configured to be driven by the motor; a trigger switch configured to allow rotation of the motor; a power supply unit configured to supply electric power to the motor; and a control unit configured to control rotation of the motor, characterized in that: the electric working machine further comprises a switching element configured to perform short-circuiting between terminals of the motor to apply electronic braking, wherein the control unit is configured to perform adjustment of the braking by controlling the switching element when stopping the motor.
Abstract:
The invention relates to the control of an inductive load by pulse width modulation from a periodic setpoint control signal having a given setpoint duty cycle. The setpoint control signal is, at each period of said setpoint control signal, in a first logic state determined from the high and low logic states during at least a first duration and in the other logic state during the rest of the period. Control signals (S21, S31) activating the inductive load are generated from the setpoint control signal (PWM). Using a first counter (3), the first duration (t0) is determined from the setpoint control signal (PWM). Using a second counter (4), a second duration (t0-td2) is determined during which a logic signal (L_Out) corresponding to an effective control signal (V,OUT) observed at the load (O1) is in the first determined logic state. The second duration, increased by the inertia td2, is slaved to the first duration. Therefore an effective duty cycle is equal to a setpoint duty cycle.
Abstract:
An electronic component comprising a half bridge adapted for operation with an electrical load having an operating frequency is described. The half bridge comprises a first switch and a second switch each having a switching frequency, the first switch and the second switch each including a first terminal, a second terminal, and a control terminal, wherein the first terminal of the first switch and the second terminal of the second switch are both electrically connected to a node. The electronic component further includes a filter having a 3dB roll-off frequency, the 3dB roll-off frequency being less than the switching frequency of the switches but greater than the operating frequency of the electrical load. The first terminal of the filter is electrically coupled to the node, and the 3dB roll-off frequency of the filter is greater than 5 kHz.
Abstract:
A method of controlling at least one motor in a motorised mobility vehicle, wherein the motor is part of a drive circuit for mobilising the mobility vehicle, the method comprising the steps of: utilising a stored profile of a motor performance parameter to develop a compensation term for controlling the motor, wherein the stored profile is of a resistance based variable associated with the motor as a function of a further variable and dynamically updating the compensation term when the mobility vehicle is in use.
Abstract:
Ein elektronisch kommutierter Motor (20) hat einen ersten Anschluss (46) zum Anschließen an einen positiven Pol einer Gleichspannungsquelle (47) und einen zweiten Anschluss (50) zum Anschließen an einen negativen Pol (50) dieser Gleichspannungsquelle (47), ferner einen Stator mit einer Statorwicklungsanordnung, welche mindestens einen Wicklungsstrang (26) aufweist, einen permanentmagnetischen Rotor (28) welcher im Betrieb bei seiner Drehung die Form des Stromes (i 1 , i 1 ') in der Statorwicklungsanordnung (26) beeinflusst, eine Erfassungsanordnung (64), welche dazu ausgebildet ist, einen aus der Gleichspannungsquelle (47) dem Motor (20) zugeführten Strom in zeitlichen Abständen zu erfassen und zu digitalisieren, welcher Strom im Betrieb vom ersten Anschluss (46) durch die Erfassungsanordnung (64) zum zweiten Anschluss (50) fließt, wobei der Absolutwert des Motorstroms (i 1 , i 1 ') im Betrieb verschiedene Abschnitte aufweist, wie folgt: einen ersten Abschnitt (113), im Folgenden Stromrücken genannt, der ausgehend von der Kommutierung (118, 1 18') bis zu einem Maximum (114) ansteigt, einen zweiten Abschnitt (115), im Folgenden Stromsattel genannt, der ausgehend vom Maximum (1 14) bis zu einem Minimum (116) absinkt, einen dritten Abschnitt (117), im Folgenden Stromschwanz genannt, der sich an den Stromsattel (11 5) anschließt; und einen programmgesteuerten Rechner (36), welcher zur Ausführung folgender Schritte ausgebildet ist: a) aus den digitalisierten Stromwerten wird die Lage des Stromrückens (113) ermittelt; b) aus den digitalisierten Stromwerten wird die Lage des Stromsattels (115) ermittelt; c) ausgehend von der erfassten Lage von Stromrücken (113) und Stromsattel (115) wird ein Stromwert (118; 118') ermittelt, bei dem ein Kommutierungsvorgang beginnen soll; d) wenn der Absolutwert des Motorstroms (i 1 , i 1 ') diesen Stromwert (118; 118') erreicht oder überschreitet, wird der Kommutierungsvorgang eingeleitet.