摘要:
The present invention provides an aqueous composition and process for electrodepositing a layer of a ductile, strongly adhering, adsorptive and/or absorptive zinc coating or zinc coating comprising silicon and phosphorous on a metal substrate. The electrodeposition composition is prepared by reacting metallic silicon and zinc with phosphoric acid and an alkali metal hydroxide in the ratio of between 0,4 and 1,3 moles of alkali metal hydroxide per mole of phosphorus acid, and adjusting the solution to a pH of 1 or higher after completion of the reaction. The coating is deposited on the metal substrate by electrodeposition and comprises about 70 to 99,5% by weight of zinc, and about 0,1 to 10% by weight of silicon, and about 0,5 to 20% by weight of phosphorus. The resulting Zn/Si/P coating improves the resistance of the metal substrate to corrosion, wear, galling, stress corrosion cracking and cracking during mechanical forming operations. While essentially all metals of industrial importance may be coated, this process is especially important for ferrous metals, steels, stainless steels, copper, aluminium, chromium and titanium.
摘要:
An over-voltage comparator and shutdown circuit for a power converter, comprising at least a first voltage divider connected between ground and a monitored voltage, the voltage divider including a first resistor and a second resistor, a switch mode regulator connected to a primary switch of the power converter, and a first threshold comparator, wherein a monitored input of the first threshold comparator connected between the first resistor and the second resistor, an anode of the first threshold comparator is connected to ground, and a cathode of the first threshold comparator connected to the switch mode regulator, and wherein the monitored voltage is voltage at an end of a primary winding of the power converter. An auxiliary output circuit of the power converter may be provided having a first output providing the monitored voltage and a second output providing power to the switch mode regulator.
摘要:
A control circuit configured to control an electromechanical brake is provided. The control circuit includes: a switching regulator configured to control a magnitude of voltage applied to a brake coil of the electromechanical brake; wherein said switching regulator includes at least one semiconductor switch, one diode, one capacitor and one inductor; the control circuit is configured such that, in operation, at least one signal from a process sub-system specifies the magnitude of the voltage for the brake coil; and at least one brake applying control signal from a safety sub-system can cause the brake coil voltage to be reduced to a level low enough to apply the brake by opening a switch and each brake applying control signal from the safety sub-system has a corresponding diagnostic feedback signal to the safety sub-system that indicates the state of the corresponding switch. A method and a system are disclosed.
摘要:
A stator arrangement particularly suitable for use in an air-cooled generator or other such electric machine includes a stator with an outer stator surface, an opening therein defining an inner stator surface, and longitudinally opposed stator end surfaces. Conductive coils are supported by the stator, and include end turns overlying the longitudinally opposed stator end surfaces. In order to block out environmental contaminants and prevent conductive coil shorting, protective barriers are mounted over the end turns and secured to the stator.
摘要:
A hybrid stepper motor includes a stator having a number of poles. Teeth are formed on the stator poles and separated from each other by slots. A magnet is inserted in the slots to a predetermined depth from a top surface of the stator teeth. The motor further includes a rotor that is provided coaxial with the stator. Teeth are also formed on the rotor opposite the stator teeth. The rotor teeth enable the rotor to be rotated relative to the stator in cooperation with the stator teeth.
摘要:
Reaction force transfer system includes a frame and a machine base supported by the frame through passive isolation structure. A carriage is supported for motion with respect to the machine base and a motor is provided having a stator coupled to the frame and a forcer coupled to the carriage to move the carriage with respect to the machine base.
摘要:
The present invention provides a highly optimized motor design enabling an increase in torque compared to a similarly sized motor of traditional design. Additionally, the present invention enables motors that provide smooth, ripple free, operation at low speeds. These advances are provided through disclosure of slot/pole ratios that provide the stated benefits.
摘要:
High precision position control apparatus. An object supported on a frame of reference (10) is moved by an actuator (14). A position sensor (16) generates a position signal and an acceleration sensor (24) affixed to the frame of reference (10) generates an acceleration signal. A control system responds to the position signal and the acceleration signal to control the actuator (14) to move the object to follow a commanded trajectory with reduced following error.