58results about How to "Precise size adjustment" patented technology

The invention discloses an active control current-limiting system for fault current and a control method thereof. The active control current-limiting system comprises series DVR modules, DC-links and a parallel converter, wherein a series side is formed by a three-single-phase structure; each phase comprises an L, a C1 filter link, a series transformer T, one DVR module and one DC-link; an each DC-link comprises a current-limiting inductor L1, a bleeder resistor rf, a D5 and a bidirectional thyristor T3. LC filters are used for filtering out harmonic waves, and the input time of the bleeder resistors is controlled through regulating the duty ratios of controlled tubes T2, so that current is limited below a specific value. Stabilized capacitors C are connected between the three-single-phase series side and the PWM parallel converter in parallel; and the PWM parallel converter is formed by a three-phase full bridge. Improvement of the voltage quality of a power network system, governance of harmonic current and a short-circuit fault current limiting function can be achieved and the electric security is improved.

An overload protection transmission gear comprises a gear outer ring and a gear inner ring which are arranged in a sleeved mode. The gear outer ring is provided with a plurality of mounting holes, and an ejection head and an ejection head spring are arranged in each mounting hole, wherein one end of the ejection head spring is matched with the ejection head, and the other end of the ejection head spring is limited into the mounting hole through an ejection head spring pin; the gear inner ring is provided with a plurality of location grooves corresponding to the mounting holes, and the location grooves are used for containing transition sections of the ejection heads. The overload protection transmission gear can control transmitted torque and prevent other parts from being damaged by overload.

The invention aims at providing a jaw frame type bionic movement mechanism fatigue test device. The jaw frame type bionic movement mechanism fatigue test device comprises a jaw frame type bionic movement mechanism, a motor, a speed reducer, a groove-cam mechanism and a base, wherein the jaw frame type bionic movement mechanism, the motor, the speed reducer and the groove-cam mechanism are arranged on the base; the speed reducer is connected with the motor and the groove-cam mechanism respectively; and the jaw frame type bionic movement mechanism is connected with the groove-cam mechanism. Thejaw frame type bionic movement mechanism fatigue test device has a simple structure, is practical, convenient to carry, intelligent to control and accurate to test, can precisely adjust the size according to various opening requirements of the activity of a multi-bending spring on the cheek side, precisely measure a fatigue period of the multi-bending spring and immediately brake when the multi-bending spring is broken, and is applied to fatigue performance test of the multi-bending spring effectively.

The invention provides a methanol electrooxidation catalyst preparation method. The preparation method comprises the steps that dispersion liquid of carbon nano-material is coated on the surface of asubstrate to obtain a template, a nitrogen-containing organic polymer film and a Pt nano-particle are deposited on the surface of the template by using an atomic layer deposition method so as to obtain a catalyst precursor, and the catalyst precursor is subjected to heat treatment under a protective atmosphere to obtain a methanol electrooxidation catalyst. According to the methanol electrooxidation catalyst preparation method, the nitrogen-containing organic polymer film and the Pt nano-particle are deposited on a carbon carrier by using the atomic layer deposition method, the nitrogen-containing organic polymer film is carbonized into a conductive nitrogen-containing carbon film after being subjected to heat treatment, and compared with a pure Pt catalyst, the methanol electrooxidation catalyst shows higher activity and stability in the methanol electrocatalytic oxidation process; and meanwhile, the methanol electrooxidation catalyst preparation method is simple and controllable, content and sizes of all components are convenient to accurately adjust, product preparation uniformity is good, and repeatability is high.

The invention belongs to the technical field of crushers, and in particular relates to a counter-roll crusher with grinding rollers with a fixed-axis support structure. The invention includes a crusher frame, the crusher frame is provided with a fixed roller part and a movable roller part, a crushing discharge port is formed between the fixed roller part and the movable roller part, and the crusher frame is provided with There are drivers. In the present invention, by setting the discharge port adjustment component, when crushing ore of different sizes, the discharge port adjustment component drives the moving roller part to move to the end close to or away from the fixed roller part, so as to adjust the size of the crushing discharge port, which can reduce the work intensity of the staff. , Precisely adjust the size of the discharge port, ensure that the size of the discharge port is consistent within the full length of the roller, and maintain the crushing discharge port, which can overcome the disadvantages of traditional models that cannot crush hard ores, and can be used in the production of metal mines, greatly reducing The cost of crushing metal mines, and at the same time, it can pass through the iron regulator during crushing. Accurately determine whether the iron is too high to ensure the safety of the equipment.

The invention discloses a multipurpose axial feeding type swirler capable of precisely adjusting and controlling a liquid phase vortex flow speed. The axial feeding type swirler is composed of a feeding pipe, a cyclone pipe, a cyclone tangential slit, a flow speed adjusting valve and an outer jacket. The feeding pipe is arranged on the center of an upper sealing cover of the outer jacket and connected with a cavity which is formed by the outer jacket and the cyclone pipe. An upper segment of the cyclone pipe is provided with an internal thread which is matched with an external thread of the flow speed adjusting valve, a middle segment or a liquid phase feeding position is provided with the cyclone tangential slit, and a lower segment extends to the exterior of the outer jacket. The flow speed adjusting valve is a cylinder, the diameter of a front segment of the flow speed adjusting valve is same as or is matched with the inner diameter of the cyclone pipe, and a rear segment of the flow speed adjusting valve is provided with an external thread. According to the core technology, the upper and lower positions of the flow speed adjusting valve are adjusted by rotating the flow speed adjusting valve, the liquid phase cyclone flow speed and the dwell time of a liquid phase in the cyclone pipe are conveniently and precisely adjusted, requirements on cyclone flow speeds, mixing degrees and reaction time of different systems are met, and the axial feeding type swirler can be used for industries of chemical engineering, metallurgy, materials, waste water treatment, medicament and the like.

The invention provides a green synthesis method of a cadmium selenide nano-cluster and a cadmium selenide nanocrystal with controllable size. In the method, a series of low toxic / economical ligands are adopted, a selenium elementary substance and cadmium oxide dispersed in a non-ligand solvent are taken as precursors, and the cadmium selenide nano-cluster and the cadmium selenide nanocrystal are synthesized in the non-ligand solvent. The size can be adjusted within 0.7nm-13nm by adjusting the proportion of the ligands and the precursors. The obtained nanocrystal has high crystallinity and narrow size distribution fwhm which equals 25 plus or minus 2nm, relatively high fluorescence quantum efficiency which is 5%-38%, and a fluorescence emission spectrum can be adjusted within 450nm-690nm.

The invention provides a carbon material with two-level pore channels, and a synthesis method thereof, wherein the carbon material comprises amorphous carbon, and has two-level pore channels. The synthesis method comprises: screening a Beta molecular sieve; placing the Beta molecular sieve in a sodium benzoate solution, and treating; mixing the Beta molecular sieve, saccharide, an auxiliary agentand water, and carrying out stirring ultrasonic treatment; carrying out drying treatment and high temperature treatment; and finally treating in an alkali solution to obtain the macroporous carbon material. According to the present invention, with the method, the expensive organic additives are not used, and the prepared macroporous carbon material has uniform pore size distribution.

The invention discloses a specimen clamping device for a large-diameter separated Hopkinson compression bar, which includes a fixed end and a sliding end, the fixed end includes a fixed sleeve, and a fixed collar is sleeved on the fixed sleeve. There are several fixing holes on the ring; the sliding end includes a sliding sleeve, and the sliding sleeve is connected to the sliding collar through a number of evenly opened chute slots; A positioning hole is opened on the collar corresponding to the position of the slider, and a positioning piece is installed in the positioning hole; a plurality of connecting holes are opened on the sliding collar, and the connecting holes and the fixing holes are respectively connected with two ends of the elastic element. The invention can solve the problems of insufficient support reliability and low positioning accuracy of the specimen clamping device in the prior art, has high reliability, small randomness and good versatility, and can be flexibly adjusted and adjusted according to the specimen size and specimen strength. Assembly, and easy to disassemble and assemble; the pre-clamping force can be adjusted in a large range and has strong applicability.

The width dynamically adjustable conveying device of the present invention is to solve the above-mentioned problems existing in the prior art and obtain the specific shape size and position of the current package based on visual recognition technology, and adopt the method of randomly adjusting the side baffles of the conveying device The opening and closing angle is expected to realize dynamic adjustment of the conveying width at any time and is suitable for fully automatic directional conveying and tallying of multi-standard parcels, so as to realize unimpeded passage of parcels, improve conveying efficiency and prevent congestion. It includes a frame and a visual recognition device arranged vertically above the frame; at least on the baffle on one side of the frame, there is an adjustable baffle driven and connected by an angle adjustment device; the angle adjustment device has a support A rod assembly and a push rod assembly, the push rod assembly includes an electric cylinder installed on the baffle, the output shaft of the electric cylinder is connected to one end of the connecting rod through a connecting fork and a joint bearing, and the other end of the connecting rod is connected to the adjustment baffle through a joint bearing; Connect the support rod assembly between the frame and the adjustment baffle.

Optical fiber wireless single sideband modulation system with self-adaptive optical load side ratio, involving optical fiber communication, long-period fiber grating, microwave photon technology, the system includes: continuous wave laser (1), two-electrode Mach-Zehnder modulator (2 ), sine wave local oscillator (3), 90-degree power splitter (4), bias voltage regulator (5), dynamic polarization controller (6), polarization beam splitter (7), first long-period optical fiber Grating (81), second long-period fiber grating (82), polarization beam combiner (9), Y splitter (10), optical fiber (11), first photodetector (121), optical interleaver (13) , a second photodetector (122), a third photodetector (123), and a current comparator (14). The above devices are connected sequentially. The invention can make the change of the optical load side ratio of the single sideband modulation signal adaptive to system parameters, and keep it at 0dB all the time, so as to maintain the system performance in the optimal state.

The invention discloses an electromagnetically controlled low-frequency ultrasonic secondary atomization nozzle, which includes a nozzle, a liquid inlet hole is opened on the nozzle, the liquid inlet hole is connected to one end of the liquid outlet hole, the end of the nozzle is a trapezoidal nozzle groove, and the trapezoidal nozzle groove is set Trapezoidal secondary atomizing mover, the other end of the liquid outlet hole is connected to the trapezoidal nozzle groove; the iron core is bonded to the trapezoidal secondary atomizing mover, coils are wound on the iron core, and the iron core is covered by a protective cover to protect The cover is bonded to the trapezoidal secondary atomizing mover; one end of the block supports the trapezoidal secondary atomizing mover, and a sponge is inserted between the block and the trapezoidal secondary atomizing mover, and the sponge is bonded to the block, and the stopper The other end is welded to the nozzle. By adjusting the circuit to change the size of the inflow current in the coil, the magnitude of the electromagnetic force can be precisely adjusted, and the distance between the trapezoidal nozzle groove and the trapezoidal secondary atomizing mover can be precisely controlled, thereby accurately controlling the size of the generated droplets.

The present invention provides a carbon material and a synthesis method thereof, wherein the carbon material comprises amorphous carbon, and has two-level pore channels. The synthesis method comprises: screening a Beta molecular sieve; placing the Beta molecular sieve in a sodium benzoate solution, and treating; mixing the Beta molecular sieve, saccharide, a silica sol and water, and carrying outstirring ultrasonic treatment; carrying out drying treatment and high temperature treatment; and finally treating in an alkali solution to obtain the macroporous carbon material. According to the present invention, with the method, the expensive organic additives are not used, and the prepared macroporous carbon material has uniform pore size distribution.