61 results about "Piezoelectric fan" patented technology

An LED lamp that includes a piezoelectric fan or synthetic jet to cool component of the lamp is disclosed.

A piezoelectric fan includes a blade that is joined to a piezoelectric oscillator that bends in response to an application of a voltage, and the blade of the piezoelectric fan is arranged to swing in a space between neighboring heat dissipating fins of a heat sink. The formation of a hole in the blade increases the amplitude of the blade and also improves the sweep effect of sweeping high-temperature air in the vicinity of the wall of the heat dissipating fin, and thus, improves the cooling capability of the piezoelectric fan.

An enclosure for a wireless device includes a first compartment and a second compartment. The first compartment is to house some or all of the electronic circuitry of the wireless device and is sealed from an exterior environment. The second compartment is adjacent to the first compartment and includes one or more piezoelectric fans to provide cooling for the first compartment. The second compartment is open to the exterior environment and provides physical protection for the one or more piezoelectric fans located therein.

A method of making a piezoelectric fan includes using a portion of the fan blade material as the substrate for the electronic circuit. By this method a single material may serve as both the substrate for the electronic circuitry and as the fanning end of the fan blade. Flex circuitry, including elements such as bleed resistors, inductors, capacitors, DC to AC conversion, shielding, or even drive circuitry, may be used. The piezoelectric material used to power the fan blade may have a Curie temperature high enough to survive reflow soldering, thus allowing the fan to be surface mountable on an electronic device. The fan may include an interconnect to facilitate connecting the piezoelectric material to the electronic circuit of the fan, and to facilitate connecting the electronic circuit of the fan to the electrical system of an electronic device. The interconnect may also facilitate mechanically mounting the fan.

The invention relates to a double-vibrator piezoelectric driving micro fan comprising two piezoelectric vibrators and a substrate. The substrate is a flat rectangular block, a pair of piezoelectric vibrator installation grooves is arranged symmetrically in the top and bottom surfaces of the substrate, and a run-through middle hole is arranged between the bottom surfaces of the two installation grooves. The two piezoelectric vibrators are respectively installed in the two piezoelectric vibrator installation grooves of the substrate, and the two piezoelectric vibrators and the middle hole of the substrate form a middle cavity. One side of the substrate is provided with an outlet hole which communicates the middle cavity with outside air. An inlet hole is arranged in the vertical direction of the outlet hole. During working, the two piezoelectric vibrators bend inward or outward and vibrate at the same time, the size of the middle cavity is reduced or increased, fluid flows into or out of the outlet hole, and gas flows into the inlet hole or flows out of the outlet hole, thus forming directional fluid drive capability output by gas from the outlet hole. The amount of volume change of the cavity in each cycle is significantly greater than that of a traditional single-vibrator piezoelectric fan. The output capability of the piezoelectric fan can be improved.

A switched mode power supply is provided. The switched mode power supply includes a transformer, which includes at least one primary winding connected to a DC voltage via a switching element and a secondary winding connected to a load via a rectifier circuit including at least one diode, and at least one piezoelectric fan which generates an air flow at the transformer and/or at the switching element and/or at the diode. The air flow produced can be guided in a targeted manner onto the components to be cooled, with the air flow remaining low and therefore, no contamination by air particles arises.

The invention discloses a lens defogging system for parking lot entrance and exit recognition cameras. The lens defogging system comprises a hot air defogging module, a heating defogging module, a sensor module and a controller. The hot air defogging module is installed between a housing and a lens, and comprises a piezoelectric fan and a heating body. The heating defogging module includes a connecting portion attached to the lens and a plurality of heating elements disposed on the connecting portion at intervals. The sensor module includes a temperature sensor and a temperature and humidity sensor. The temperature sensor is installed on the outer surface of the housing. The temperature and humidity sensor is mounted on a side between the housing and the lens and away from the hot air defogging module. The lens defogging system combines two high-efficiency defogging modes including a heating defogging mode and a hot air defogging mode, compares the internal temperature of the camera with the external temperature by the controller, compares the internal humidity with the set humidity, and automatically selects a proper defogging solution according to a comparison result so as to automatically and efficiently defog the lens.

The invention relates to a resonance piezoelectric fan with a cymbal-shaped cavity. The fan comprises a piezoelectric oscillator, a supporting block, a mass block and a base, and is characterized by further comprising a cymbal-shaped cavity structure, wherein the piezoelectric oscillator is arranged on the base, and the side, in the thickness direction, of the piezoelectric oscillator is connected with the supporting block; the supporting block is connected with a first cymbal-shaped cavity element of the cymbal-shaped cavity, the first cymbal-shaped cavity element is provided with taper air inlet holes, a second cymbal-shaped cavity element is provided with flow passing holes, the second cymbal-shaped cavity element is connected with the mass block, an opening of the first cymbal-shaped cavity element and an opening of the second cymbal-shaped cavity element are oppositely arranged and connected in a sealed mode to form a cymbal-shaped pump cavity, and taper outlet holes are distributed in the positions, corresponding to the flow passing holes, of the mass block; during work, the piezoelectric oscillator vibrates under the action of alternating voltage, so that the volume of the cymbal-shaped pump cavity changes, fluids are pushed to flow in from the air inlet holes and flow out from the air outlet holes, and the resonance piezoelectric fan has the advantages of being compact in structure and large in cavity size variable quantity.

The invention relates to the technical field of heat dissipation, in particular to a piezoelectric fan, a radiator and electronic equipment. The piezoelectric fan comprises a fan body and piezoelectric element, wherein an generating cavity and a flow spraying cavity are formed in the fan body, the generating cavity communicates with the flow spraying cavity through a flow spraying opening, a flowinlet and a flow outlet are formed in the fan body, and the flow inlet and the flow outlet communicate with the flow spraying cavity. The flow outlet is arranged corresponding to the flow spraying opening, and fluid discharged by the generating cavity forms a jet flow through the flow spraying opening, and the jet flow penetrates through the flow spraying cavity and is sprayed out of the fan bodythrough the flow outlet. The piezoelectric element is arranged in the fan body, and a piezoelectric element vibrates to change the volume of the generating cavity. According to the piezoelectric fan,the radiator and the electronic equipment, the technical problems of unstable output air flow, low service life, and mere local circulation of air in the prior art are solved.

The invention discloses a piezoelectric ceramic fan with a sensing function. The piezoelectric ceramic fan with the sensing function comprises piezoelectric ceramic plates, a composite material layer, a metal sheet and a mounting base, wherein the number of the piezoelectric ceramic plates is two, and the piezoelectric ceramic plates adhere to the two corresponding surfaces of the composite material layer in the positive, negative, positive and negative polarization directions; one end of each piezoelectric ceramic plate is connected with the metal sheet, the other end of each piezoelectric ceramic plate is installed in the mounting base, and outgoing lines arranged on the piezoelectric ceramic plates and the composite material layer are guided out of the mounting base; two independent piezoelectric ceramic areas are divided on the electrode surface of a piezoelectric ceramic positive electrode, and include a sensor function area and a drive use area. According to the piezoelectric ceramic fan with the sensing function, due to the fact that a piezoelectric sensing portion in a piezoelectric fan assembly is detected and controlled, the resonant frequency of the piezoelectric fan assembly is consistent to the power source output frequency, fan blades can achieve the maximum swing amplitude, and the optimal heat dissipation effect can be achieved.

The invention discloses a piezoelectric fan with double bodies working alternatively. The piezoelectric fan comprises piezoelectric ceramic chips, a composite material layer and a metal sheet. The number of the piezoelectric ceramic chips is two, one piezoelectric ceramic chip is positive in polarization direction, the other piezoelectric ceramic chip is negative in polarization direction, and the two piezoelectric ceramic chips are adhered to the two corresponding faces of the composite material layer respectively. One end of each piezoelectric ceramic chip is connected with the metal sheet, and the other end of each piezoelectric ceramic chip is connected with an electrode, wherein one piezoelectric ceramic chip is connected with a negative electrode, and the other piezoelectric ceramic chip is connected with a positive electrode. According to the piezoelectric fan with the double bodies working alternatively, the two bodies are used for alternative working, piezoelectric ceramic can rest for half of the time, over fatigue of the piezoelectric ceramic can be lowered, the flexibility of vanes is improved, the piezoelectric fan can also achieve the best swing amplitude, and the best effect of the fan is guaranteed. The metal sheet is used as a metal amplifier, the metal sheet is made of high-quality alloy materials, good elasticity is achieved, and the best fan effect is achieved.

A piezoelectric fan includes a vibration plate one end of which in a length direction is supported in a fixed manner and the other end of which in the length direction is a free end; and piezoelectric elements, attached on at least one of front and back surfaces of the vibration plate. In an intermediate portion of the vibration plate in the length direction, a right-angle bent portion is provided, and a plurality of divided blades are defined by slits in an area of the vibration plate extending from the free end to a position located a predetermined distance from the bent portion toward the free end. The piezoelectric element is attached on the portion of the vibration plate between the fixed end and the bent portion. Hence, variations in resonant frequency among the blades are reduced and the blades are efficiently excited using a common piezoelectric element.

A heat dissipating system including a casing body, a heat source and a piezoelectric fan is provided. The casing body includes an upper casing and a bottom case, wherein at least one of the upper casing and the bottom casing includes at least one air inlet. The heat source and the piezoelectric fan are both disposed in the casing body. The piezoelectric fan has an opening facing the heat source while the air inlet is adjacent to the opening. Air is adsorbed into the opening through the air inlet and is exhausted out towards a direction of the heat source by the piezoelectric fan.

The invention provides a piezoelectric fan inherent frequency measuring method and a piezoelectric fan. The method comprises the steps that a plurality of first frequencies are selected from the first frequency range of voltages input to the piezoelectric fan, the voltages of the multiple first frequencies are sequentially input to the piezoelectric fan correspondingly, and the input time lasts for the first preset time; the voltages of the multiple first frequencies are stopped being input to the piezoelectric fan correspondingly; the amplitude values of sampled signals of the voltages of the multiple first frequencies are obtained correspondingly within the time duration of the piezoelectric effect; and amplitude values, meeting the first preset condition, of the amplitude values of the sampled signals of the voltages of the multiple first frequencies are determined, and the first frequency of the voltage which corresponds to the amplitude value meeting the first preset condition is determined to be the real-time inherent frequency of the piezoelectric fan. The real-time inherent frequency of the piezoelectric fan can be determined according to the amplitude values of the sampled signals of the voltages of the multiple first frequencies, accordingly, the inherent frequency of the piezoelectric fan can be tracked effectively, and the piezoelectric fan can work stably for a long time.

The invention relates to a piezoelectric fan with laminating type blades. The piezoelectric fan comprises an elastic metal sheet and a piezoelectric ceramic sheet, wherein the piezoelectric ceramic sheet is bonded and fixed on the edge of one side of the elastic metal sheet, an upright support is arranged on the other side surface of the elastic metal sheet, and a thin film is arranged on one-quarter to one-half position of the upper portion of the support; the elastic metal sheet and the upright support form a L-shaped framework; and the material of the support is a PMMA organic material, andthe material of the thin film is polytetrafluoroethylene. The two sides of the piezoelectric ceramic sheet are connected to the positive electrode and the negative electrode of an alternating-currentdriving power supply, a power supply provides alternating voltage which is consistent with the system resonant frequency, and the piezoelectric ceramic sheet expands and contracts under the alternating voltage and then is subjected to displacement amplification through the L-shaped framework, so that wind sweeping and heat dissipation is realized on the thin film. According to the piezoelectric fan with the L-shaped framework laminating type blades, a grid-shaped support and the thin film are adopted to form a framework laminating type structure, so that good air impedance matching is realized, the end mass is not increased, air sweeping areas are increased, and the efficiency of air outlet and heat dissipation of the piezoelectric fan is improved.

The invention discloses a double-member alternating-working piezoelectric fan insulation structure and an electric fan thereof. The structure is a three-layer insulation structure arranged at the external side of a piezoelectric fan and comprises a bottom layer insulation layer, a high-molecular adhesive tape and a top layer insulation layer. The bottom layer insulation layer is connected with the piezoelectric fan chip. The high-molecular adhesive tape adheres the bottom layer insulation layer and the top layer insulation layer. The three-layer structured composite insulation layer is adopted so that a situation that insulation performance of the piezoelectric fan cannot be guaranteed due to fatigue cracking of material caused by long time of bending and deformation of single-layer single insulation material and finally the piezoelectric fan fails to work can be overcome; and a situation that insulation performance reduces due to separation between the piezoelectric fan chip and the insulation layer caused by weak wrapping of the insulation layer because of difference of thermal expansion coefficients when single material wraps multiple materials and then the piezoelectric fan fails to work early can also be overcome. The three-layer structured composite insulation layer is adopted so that internal stress of the single-layer structured insulation layer can be greatly reduced, affinity with the piezoelectric fan chip is enhanced and combination of the insulation layer and the chip is enabled to be firmer.