1840 results about "Pulse control" patented technology

Method and devices for delivering pulsed RF ablation energy to enable the creation of lesions in tissue are disclosed. The delivery of RF energy is controlled such that the generator power setting remains sufficiently high to form adequate lesions while mitigating against overheating of tissue. An ablation catheter tip having high-thermal-sensitivity comprises a thermally-insulative ablation tip insert supporting at least one temperature sensor and encapsulated, or essentially encapsulated, by a conductive shell. A system for delivering pulsed RF energy to a catheter during catheter ablation comprises an RF generator and a pulse control box operatively connected to the generator and configured to control delivery of pulsatile RF energy to an ablation catheter comprising at least one temperature sensor mounted in its tip. Also disclose is a method of controlling the temperature of an ablation catheter tip while creating a desired lesion using pulsatile delivery of RF energy.

A system for pulsed synchronized laser cutting of stents and/or other medical products includes a numerical controller and a machine for moving a tube of material during cutting. A pulsed fiber laser is configured to cut the tube into, for example, a stent, the numerical controller being in communication with the machine and configured to send movement control information to the machine. The numerical controller may also receive movement speed information from the machine. The numerical controller is also in communication with the pulsed fiber laser and is configured to send pulse control information to the pulsed fiber laser. The numerical controller is configured to cause average laser power to decrease by decreasing frequency of laser pulses as stent cutting speed decreases, and to cause average laser power to increase by increasing frequency of laser pulses as stent cutting speed increases.

Disclosed is a laser radar apparatus. The laser radar apparatus includes: a light transmission unit configured to output a laser pulse by using a light source; a light reception unit configured to receive a reflected laser pulse in connection with the laser pulse; and a controller configured to adjust a repetition rate of the laser pulse of the light source, in which the controller adjusts the repetition rate of the laser pulse based on at least one of reception power, a target distance, a movement speed, a vertical angle, and a radiation angle.

An LED driving circuit of a backlight unit includes a switch connected between an input of direct voltage and a ground to switch the direct voltage according to a switching pulse; a rectifying diode connected between a connecting node and one terminal of the LED array to rectify driving voltage supplied according to switching operation of the switch; a smoothing capacitor having one terminal connected to a cathode of the rectifying diode and the other terminal connected to a ground; a voltage detecting resistor connected between the other terminal of the LED array connected to the ground and the other end of the smoothing capacitor to detect voltage from the current flowing to the ground; and a PWM controlling part for controlling on/off status of the switching according to the switching pulse, wherein the switching pulse has a duty ratio determined according to a preset internal reference voltage and the voltage detected by the voltage detecting resistor. The driving current of can be controlled at a constant current and thus be stabilized.

Apparatus and method for the removal of lens tissue includes a first handpiece having a laser emitting probe sized for insertion into a lens capsule and radiating a lens therein. The laser emitting probe includes a lumen for introducing irrigation fluid into the lens capsule. A second handpiece includes a pulsed controlled vibrated needle for insertion into the lens capsule and emulsifying laser eradiated lens tissue. The vibrated needle includes a lumen therethrough for aspiration of emulsified lens tissue and irrigation fluid.

The invention discloses an electronic expansion valve, which comprises an electrical control part and a mechanical part. The electrical control part comprises a bus signal reception/transmission module, a central processing module and a stepper motor driving module; wherein the bus signal reception/transmission module is used for receiving a bus control signal and transmitting the bus control signal to the central processing module; the central processing module is used for extracting valve opening information included in the bus control signal, generating a corresponding pulse control signalin combination with current position information of a stepper motor read from a data storage module, and outputting the pulse control signal to the stepper motor driving module; and the stepper motordriving module is used for driving the stepper motor to adjust the valve opening according to the pulse control signal. The invention also discloses a stepper motor and a reversing valve. The number of drive wires directly connected with a main control board can be reduced, the structure of the main control board can be simplified, and the manufacturing cost can be saved.

The invention discloses a data processing and transmitting system of high-speed multichannel CCD (charge-coupled device), which comprises a CCD analog front end, a data processing unit, a high-speed serial transmission unit and a high-speed image data collection system which are sequentially connected. The CCD analog front end is used for converting an analog signal output by a CCD detector and subjected to sampling and pulse control into n channels of digital image data via n A/D (analog/digital) converters, transmitting the digital image data to the data processing unit, and acquiring data of each channel at the same time. The data processing unit is used for transmitting single-channel high-speed data streams, a data transmitter clock and a horizontal synchronizing signal acquired from integration of the digital image data to the high-speed serial transmission unit. The high-speed serial transmission unit is used for converting single-channel high-speed data streams via LVDS (low-voltage differential signaling) serial chips into high-speed LVDS data streams for transmitting. The high-speed image data collection system is used for collecting the high-speed serial LVDS data streams and realizing real-time storing and displaying of the image data.

Light load efficiency of a power factor correction circuit is improved by adaptive on-time control and providing for selection between a continuous conduction mode and a discontinuous conduction mode wherein the discontinuous conduction mode increases time between switching pulses controlling connection of a cyclically varying voltage to a filter/inductor that delivers a desired DC voltage and thus can greatly reduce the switching frequency at light loads where switching frequency related losses dominate efficiency. The mode for controlling switching is preferably selected for each switching pulse within a half cycle of the cyclically varying input voltage. A multi-phase embodiment allows cancellation of EMI noise at harmonics of the switching frequency and adaptive change of phase angle allows for cancellation of dominant higher order harmonics as switching frequency is reduced.

Provided are a system and method for saturating a gas with a vapor from a liquid chemical. The system includes: (a) a saturation vessel connected to receive a liquid chemical and a carrier gas; (b) a gas sparger in the saturation vessel for sparging the carrier gas into the liquid chemical; (c) means for maintaining the liquid chemical in the saturation vessel at a substantially constant level; (d) means for controlling the temperature of the liquid chemical in the saturation vessel to a desired value, comprising (I) a system for cooling the liquid chemical, and (ii) a heater inside the saturation vessel extending vertically in the liquid a distance at least half of the height of the liquid chemical level for heating the liquid chemical; and (e) means for controlling the pressure of the saturated gas to a desired value. The invention also relates to novel methods and systems for controlled delivery of a vaporized liquid chemical. The invention has particular applicability to the semiconductor manufacturing industry.

A gate driver for performing gate shaping on a first transistor of having gate, source, and drain terminals, the first transistor being selected from a switching stage of a power switching circuit having high- and low-side transistors series connected at a switching node for driving a load. The gate driver includes the following steps: upon receipt of an ON pulse pre-charging the gate terminal until gate to source terminal voltage equals Vth, controlling the di/dt(ON) flowing in the first transistor while free wheeling current is flowing in a second transistor of the switching stage, and controlling the dv/dt(ON) of the first transistor while a charge on the gate terminal is present; and upon receipt of an OFF pulse controlling the dv/dt(OFF) of the first transistor until free wheeling current is flowing in the second transistor, and controlling the di/dt(OFF) flowing in the first transistor while the gate to source terminal voltage equals Vth.

A method and an apparatus for transporting thermal energy produced in a motor vehicle provides that the waste heat of an electronic component (42), such as a pulse-controlled inverter, be utilized to heat other vehicle parts, such as the internal combustion engine (12) or the passenger compartment. To that end, preferably two coolant circuits (10, 40) are provided, which can be coupled to one another or decoupled from another in order to control the flow of heat.

A contactor may operate to interrupt current in a circuit while the circuit is operating under load. A shunt is provided to by-pass surge power current around contacts to reduce arcing. The shunt includes a solid-state switch that may be operated in a series of pulses during movement of the contacts. The pulse control unit may detect a potential for arcing and then provide for periodic pulsing operation of the shunt. Because the solid-state switch may operate discontinuously, the contactor may be constructed with a switch that is selected on a basis of its pulse rating.

The invention discloses a control method of a three-phase grid-connected inverter based on a modified proportional resonant regulator. The method comprises the following steps of: firstly, computing according to given active and reactive powers of the inverter and a voltage of a power grid to obtain required d-axis and q-axis currents under a synchronous coordinate system, and performing coordinate transformation by combining with phase information which is measured by a phase locking loop and a measured three-phase voltage signal of the power grid to obtain a current reference signal under a stationary alpha-beta coordinate system; secondly, performing coordinate transformation on an output current signal of the inverter to the alpha-beta coordinate system, controlling and tracking the current reference signal by the modified proportional resonant regulator with a harmonic compensator; and finally, returning to an abc coordinate system by coordinate transformation to generate a pulse-width modulation (PWM) pulse-control three-phase full-bridge inverter output, so as to make a distributed generation system grid-connected for power generation. By the method, a large number of complicated computation processes are eliminated, and a control structure is simplified. The control method of the three-phase grid-connected inverter based on the modified proportional resonant regulator is an accurate and high-efficiency novel inverter control method and has a bright development future.

The invention relates to a magnetic pulse forming device and method of a bimetal composite pipe, relates to magnetic pulse forming devices and methods of composite pipes, and is is used for solving the problems of the composite bimetal pipe having the disadvantages of being low in combination intensity and limited in application occasions by adopting a cold forming method, as well as is high in investment and complex in production process by adopting a thermal processing method, and is high in dangerousness by adopting an explosion composite method. A pair of movable flat tongs is glidingly matched with a base fixing plate; a pair of fixed flat tongs is fixedly arranged on the base fixing plate; a pipe billet clamping block is fixedly arranged on the flat tongs; a screw rod is connected with the base fixing plate; the screw rod is installed on the movable flat tongs; a support frame is fixedly connected with the base fixing plate; a magnetic trap is supported through the support frame; a magnetic coil is wound on the outer annular surface of the magnetic trap; two output ends of a magnetic pulse control circuit are connected with two ends of the magnetic coil; and the method comprises the following steps of: cleaning the surface of a pipe billet to be composited; locating and clamping internal and external pipe billets; compositing and forming for first time; and subsequently and progressively compositing and forming till the bimetal composite pipe with required length is obtained. The magnetic pulse forming device and method of the bimetal composite pipe, disclosed by the invention, are used for magnetic pulse forming of the bimetal composite pipe.

The invention relates to a method for controlling drive pulses of a DAB type bidirectional isolation DC-DC converter. The method for controlling the drive pulses of the DAB type bidirectional isolation DC-DC converter comprises the steps of firstly, carrying out drive pulse control on the DAB type bidirectional isolation DC-DC converter based on a drive pulse working principle; and then inferring relevant formulas in the mode of control, and carrying out characteristic analysis and verification. The method for controlling the drive pulses of the DAB type bidirectional isolation DC-DC converter only needs to control a single variable, is simple and practical, applicable to the state of light load of a system, simple in algorithm, convenient to achieve, and prone to feedback regulation, reduces stress of devices, and effectively improves system efficiency when the system is in light load.

The invention discloses a device and method for forming small-diameter flanging holes in an aluminum alloy plate through magnetic pulses, and belongs to the field of metal plate part plastic forming and manufacture. The device and method solve the problems that when the flanging holes are formed in the aluminum alloy plate through an existing magnetic pulse forming technology, the service life of a coil is short, damage easily happens to the machined workpiece, a plurality of flanging and forming procedures exist when a steel die is adopted, and the forming quality is not stable. A coil wire turn is packaged in a coil framework, a flanging female die is fixed to a bottom plate, the upper section of a positioning ring and the lower section of the positioning ring are arranged in a columnar magnetic trap and the flanging female die, a magnetic trap limiting ring is arranged on the upper end face of the columnar magnetic trap, the solenoid coil is arranged on the outer side wall of the columnar magnetic trap and the outer side wall of the magnetic trap limiting ring in a sleeved mode, and a longitudinal seam is formed in the side wall of the columnar magnetic trap. An upper pressing plate is arranged on the upper end face of the magnetic trap limiting ring and the upper end face of the coil framework. The aluminum alloy plate is arranged between the flanging female die and the coil framework, and two output ends of a magnetic pulse control circuit are connected with two wiring terminals of the coil wire turn. The device and method are used for forming the small-diameter flanging holes in the aluminum alloy plate through magnetic pulses.

Flush syringe assemblies capable of creating pulsatile movement of the plunger rod as it moves in the distal direction within a syringe barrel, while preventing overpressurization of the cathether are provided. An exemplary flush syringe assembly includes a syringe barrel with a first pulsing element and a chamber with flush solution, a plunger rod with a stopper and a second pulsing element that interacts with the first pulsing element to provide an engagement force that causes pulsatile movement of the plunger rod and a thumb press slidably attached to the plunger rod with a pulse control element. The pulse control element is compressible to create a compression force that is greater than the engagement force of the first pulsing element and the second pulsing element.

The present invention provides a control device capable of improving hysteresis characteristics of a voice coil motor (31) and attaining a suitable lens position without complicating the structure of the control device. As solving means of the invention, a voice coil motor control device (30) includes a driving current control part (34) that controls a driving current supplied to the voice coil motor (31) in accordance with a driving pulse subjected to pulse width modulation, and a driving pulse control part (32) that divides a drive period of the voice coil motor (31) into a movement period and a holding period, and controls the driving pulse by changing the duty ratio of the driving pulse during the movement period in accordance with a duty setting value and fixing the duty ratio of the driving pulse during the holding period to the duty setting value.