Abstract: A self-propelled warning device used for road safety includes a bracket, a warning sign mounted to an upper side of the bracket, and at least one driving mechanism. The driving mechanism includes a supporting leg, a driving unit, and a wheel. The supporting leg includes a receiving portion, the receiving portion defines an accommodating space. The driving unit is accommodated in the accommodating space. The wheel is mounted on the receiving portion and is drivingly connected to the driving unit. The wheel is driven by friction of the driving unit. The driving mechanism is also disclosed.

Abstract: A warning device used for road safety includes a warning sign and a driving mechanism. The driving mechanism includes a base, a driving unit, at least one wheel, a plurality of supporting units, and a plurality of driving members. The driving unit is accommodated in the base. The at least one wheel is connected to and driven by the driving unit. The plurality of supporting units are movably connected to the base. The plurality of driving members can manipulate the supporting units. Each of the supporting units is movable between a receiving or retracted position and a supporting or extended position. For stability in placement, the device can be lifted a small distance above the road by the supporting units when these are deployed. The driving mechanism is also disclosed.

Abstract: A warning device used for road safety includes a warning sign and a driving mechanism. The driving mechanism includes a base, a driving unit, at least one wheel, a plurality of supporting units, and a plurality of driving members. The driving unit is accommodated in the base. The at least one wheel is connected to and driven by the driving unit. The plurality of supporting units are movably connected to the base. The plurality of driving members can manipulate the supporting units. Each of the supporting units is movable between a receiving or retracted position and a supporting or extended position. For stability in placement, the device can be lifted a small distance above the road by the supporting units when these are deployed. The driving mechanism is also disclosed.

Abstract: A traffic warning device includes a reflective warning plate and a foldable driving mechanism. The foldable driving mechanism includes a supporting bracket; a warning sign mounted to an upper side of the supporting bracket, and a plurality of walking or motion units mounted to a lower side of the supporting bracket. Each walking unit includes a supporting leg, a wheel rotatably connected to an end of the supporting leg, and a fastening unit. The other end of the supporting leg is rotatably connected to the supporting bracket. The supporting leg is rotatable between a folded position and a deployed position. The foldable driving mechanism is also disclosed.

Abstract: A self-propelled warning device used for road safety includes a bracket, a warning sign mounted to an upper side of the bracket, and at least one driving mechanism. The driving mechanism includes a supporting leg, a driving unit, and a wheel. The supporting leg includes a receiving portion, the receiving portion defines an accommodating space. The driving unit is accommodated in the accommodating space. The wheel is mounted on the receiving portion and is drivingly connected to the driving unit. The wheel is driven by friction of the driving unit. The driving mechanism is also disclosed.

Abstract: A system for calculating a distance travelled by a warning device moving towards a required location includes an obtaining module, a first calculating module, a counting module, and a second calculating module. The number of pulses required to turn a motor through one revolution is obtained, and the first calculating module calculates a moving distance of the device per pulse according to the number of pulses and an outer diameter of a wheel. The counting module counts a total pulses issued as the warning device moves from start to finish of a movement. The second calculating module calculates a first moving distance of the warning device according to the total pulses and the distance moved per pulse, also applying rearward image-taking of an object at start and finish of a movement, to confirm calculations. A distance sensing method of the warning device is also provided.

Abstract: A rectifier includes a first diode, a second diode, a first switch and a second switch. Each of the first switch and the second switch includes a controlling pole, a first connecting pole and a second connecting pole. A positive pole of the first diode, the second connecting pole of the first switch, and the controlling pole of the second switch are coupled to a first pole of an alternating current (AC) power. A positive pole of the second diode, the second connecting pole of the second switch, and the controlling pole of the first switch are coupled to a second pole of the AC power. A negative pole of the first diode and a negative pole of the second pole are coupled to an output pole, and the first connecting pole of the first switch and the first connecting pole of the second switch are grounded.

Abstract: A wireless charging system uses a transformer to adjust output voltage of the charging antenna to reduce the voltage in the resonant capacitor for a wireless charging coupling.

Abstract: A wireless charger includes a wireless charging transmitter. The wireless charging transmitter includes a transmission antenna, a driving circuit, a transmission temperature sensor, and a controller. The driving circuit can output a charging signal in a fast charging mode initially. The transmission temperature sensor can detect a transmission temperature value of the transmission antenna. The controller can receive the transmission temperature value from the transmission temperature sensor. The driving circuit is can output the charging signal in a fast charging mode initially. When the transmission temperature value is greater than an overheat value, the controller can control the driving circuit to output in a slow charging mode.

Abstract: An alternating current to direct current converter system includes an alternating current power supply, an external electronic load, a first MOS transistor, a first control module, a first switch and a second control module. The alternating current power supply includes a first output end and a second output end. The first control module controls the first MOS transistor to active when the first output end has a positive voltage and control the first MOS transistor to turn off when the second output end has a positive voltage. The first switch connects to a first end of the external electronic load and the second output end. The second control module connects to the first switch. The second control module controls the first switch to active when the second output end has a positive voltage and controls the switch to turn off when the first output end has a positive voltage.

Abstract: An alternating current to direct current converter system includes an alternating current power supply, an external electronic load, a first MOS transistor, a first control module, a first switch and a second control module. The alternating current power supply includes a first output end and a second output end. The first control module controls the first MOS transistor to active when the first output end has a positive voltage and control the first MOS transistor to turn off when the second output end has a positive voltage. The first switch connects to a first end of the external electronic load and the second output end. The second control module connects to the first switch. The second control module controls the first switch to active when the second output end has a positive voltage and controls the switch to turn off when the first output end has a positive voltage.

Abstract: A rectifier includes a first diode, a second diode, a first switch and a second switch. Each of the first switch and the second switch includes a controlling pole, a first connecting pole and a second connecting pole. A positive pole of the first diode, the second connecting pole of the first switch, and the controlling pole of the second switch are coupled to a first pole of an alternating current (AC) power. A positive pole of the second diode, the second connecting pole of the second switch, and the controlling pole of the first switch are coupled to a second pole of the AC power. A negative pole of the first diode and a negative pole of the second pole are coupled to an output pole, and the first connecting pole of the first switch and the first connecting pole of the second switch are grounded.

Abstract: A wireless charger includes a wireless charging transmitter. The wireless charging transmitter includes a transmission antenna, a driving circuit, a transmission temperature sensor, and a controller. The driving circuit can output a charging signal in a fast charging mode initially. The transmission temperature sensor can detect a transmission temperature value of the transmission antenna. The controller can receive the transmission temperature value from the transmission temperature sensor. The driving circuit is can output the charging signal in a fast charging mode initially. When the transmission temperature value is greater than an overheat value, the controller can control the driving circuit to output in a slow charging mode.

Abstract: A wireless charger system includes a charging module and at least one receiving module. The receiving module is configured to receive a power from the charging module wirelessly for charging a device. The charging module includes a source module, a control module, and a charging antenna. The receiving module includes a receiving antenna and a converting module. The control module is also configured to detect a perturbation of a current of the charging module. When the perturbation is detected, the control module is configured to increase a voltage outputted from the source module; when the perturbation is not detected, the control module is configured to decrease the voltage outputted from the source module. The disclosure further provides a wireless charger method.

Abstract: To monitor temperatures at multiple areas of class D/E power amplifier, DC/DC converting unit and an antenna in a wireless charger, place a thermal conductive and electro-insulative layer covering the class D/E power amplifier, the DC/DC converting unit and the antenna, and use one temperature sensor to sense the temperature of the thermal conductive and electro-insulative layer.

Abstract: A buck converter includes a pulse width modulation unit, a first switch, a second switch, an inductance, and a sensor near the inductance. The pulse width modulation unit controls the first switch and the second switch power to allow or disallow electrical conduction. The sensor senses the state of the inductance in respect of a sound event, a vibration event, and a drop in current level. When the inductance is saturated and gives rise to one or more of the foregoing events, the sensor sends a signal to the pulse width modulation unit, which controls the first switch to cut off power and the second switch to allow conduction, allowing the inductance to release all its electrical energy.

Abstract: A rectification circuit includes a first input terminal, a first switch, an energy storage circuit, a first diode, a filtering circuit connected in series and in order to ground, a second diode, and a controller. Two opposite terminals of the second diode are connected to a first node between the first diode and the filtering circuit and a second node between the first switch and the energy storage circuit. The controller transmits control signals to the first switch and the second switch to control conductivities of the first switch and the second switch.

Abstract: A maximum power point tracking (MPPT) system and method applied to a photovoltaic (PV) device includes an MPPT device and a temperature control device within a load module. The MPPT system includes a control unit, a detection unit, and a determination unit and a first command to increase power to the temperature control device and the detection unit detects output power before the command and output power after the command. The determination unit determines whether the second output power is greater than the first output power. The control unit repeats the first command to the temperature control device when the second output power is greater than the first output power.

Abstract: A direct current (DC) to alternating current (AC) converter circuit without magnetic components includes a controller, a first DC power supply, a second DC power supply, a first electronic switch, a second electronic switch, a first output terminal, and a second output terminal. The controller controls the first electronic switch and the second electronic switch to turn on and off, to coordinate the outputs of positive and negative voltages from the first output terminal and the second output terminal to present and output an AC voltage. A cycle of the AC is equal to a cycle of a main power supply, and an average of an absolute value of a voltage of the AC is equal to an average of an absolute value of a voltage of the main power supply.

Abstract: A solar power supply device includes a solar panel converting solar energy to electrical power with a DC voltage, a voltage convertor connected to the solar panel, a control unit, and a PWM signal processing unit. The voltage convertor converts the DC voltage to a power voltage to power the electrical equipment. The control unit outputs a first and a second PWM signal, and adjusts duty cycles of the first PWM signal and/or the second PWM signal by determining whether the electrical power output by the solar panel can drive the electrical equipment. The PWM signal processing unit multiplies the first PWM signal and the second PWM signal to obtain a third PWM signal, and output the third PWM signal to the voltage convertor to control the voltage convertor to output the corresponding power voltage.