36results about How to "Reduce the influence of magnetic field" patented technology

A magnetic sensor (32) detects an external magnetic field (m) to invade from the outside of an X-ray image tube (11) into an electron lens area (23), and a coil (33) arranged in an input face area (21) of the X-ray image tube (11) generates a magnetic field to cancel the external magnetic field (m) so that the influence of the external magnetic field (m) is eliminated to correct the distortion. The magnetic sensor (32) is arranged in the area, which is surrounded by a magnetic shield (20) of the X-ray image tube (11), and in the outer circumference area on the side of the electronic lens area (23) spaced from the input face area (21) of the X-ray image tube (11). The magnetic sensor (32) is less influenced by the magnetic field, which is generated by the coil (33) arranged on the side of the input face area (21) of the X-ray image tube (11), so that it detects the external magnetic field (m) to invade into the electron lens area (23), highly precisely. As a result, a distortion correcting device (31) of the X-ray image tube (11) can correct the distortion automatically.

The invention provides a device used for X-ray CT equipment to observe growth characteristics of natural gas hydrate in a blind pipe and belongs to the field of flow assurance in the delivery process of oil and gas. In-situ generation of the natural gas hydrate in the blind pipe of an oil-gas pipeline can be simulated, and growth conditions of the natural gas hydrate can be observed through the X-ray CT equipment. After liquid is injected into a reaction kettle and after leakage detection, gas is injected into the reaction kettle through a constant-pressure pump, and consumption of the gas is recorded to evaluate the growth conditions of the hydrate. During detection, a magnetic stirring system is used for stirring liquid in the reaction kettle, simulating flow of a liquid phase in the pipeline and promoting mutual cooperation of gas-liquid phases to generate hydrate. Every other certain period, X-ray CT photographing is conducted in the reaction kettle, the growth condition of hydrate in the blind pipe is observed, and growth characteristics of the hydrate in the blind pipe are studied. Measuring results are used for on-site guidance of a seabed oil-gas delivery system, and a powerful theoretical support can be provided for deep studying of hydrate risk control technology.

The invention provides a nano-precipitate image acquisition method based on scanning electron microscope backscattering mode. The method includes the following steps: sample pretreatment, electrolytic double-spray thinning, low-temperature erosion, and scanning electron microscope shooting to obtain the nano-precipitate morphology image. The invention achieves the purpose of improving the electrical conductivity of the sample and reducing the influence of magnetism by reducing the thickness of the sample, thereby improving the imaging quality of the nano-precipitate image in the steel material under the scanning electron microscope. Compared with the traditional sample preparation and shooting methods, it can obtain more Higher magnification and clearer images have certain significance for the observation of precipitate morphology and the statistics of size and distribution.

The invention provides a well wall crack printing device which comprises an inner frame structure body with a central passage and at least one printing mechanism which can be radially and movably installed in at least one mounting ring groove, wherein the inner frame structure body is provided with at least one mounting ring groove along an axial direction, the printing mechanism comprises at least three mounting brackets arranged in a circumferential direction, and the outer side of each of the mounting brackets is provided with a printing structure layer. According to the well wall crack printing device, cracks and holes of different lithology in a well wall in a formation can be obtained, such as parameters of shape, length, width, number distribution and direction, and the well wall crack printing device has the advantages of simple structure and convenient operation.

A cathode ray tube comprising: a panel whose outer surface is substantially planar; a shadow mask mounted at a distance from the inner surface of the panel, having a plurality of holes for electron beams to pass through, and forming a pincushion shape in which the long and short sides of the shadow mask are recessed toward the inside; and a shadow mask frame for fixing and supporting the shadow mask in which the long and short sides of the shadow mask frame start from the end Inclined toward the center, this is to maintain a predetermined interval from the long and short sides of the shadow mask. Thereby, the strength of the shadow mask is increased, and the influence of the magnetic field is reduced, thus obtaining excellent performance.

The invention provides an experimental device for forming a hydrate in a combined multi-phase fluid pipeline, and belongs to the field of hydrate flowing safety. The device is characterized in that a liquid phase is arranged in a reaction kettle, and a gas is injected into the reaction kettle by boosting of a gas booster pump; a window on the cylinder body of the reaction kettle can be used for observing the forming condition of hydrate in the reaction kettle; a cooling liquid with which a jacket outside the reaction kettle is filled is used for controlling temperature of the reaction kettle, and temperature and circulation of the cooling liquid is controlled by a temperature-control water bath; and temperature and pressure signals in the hydrate forming process are collected by a data collection system. Two methods are provided for using the device, according to the first using method, the reaction kettle is used as a shaking kettle, the reaction kettle on a shaking rack is driven by a motor in a power shaking system, the center of the kettle body is used as a fulcrum, and two ends of the reaction kettle swing up and down, so that gaseous and liquid phases in the reaction kettle are driven to be mutually mixed; and according to the second using method, the reaction kettle is used as a stirring kettle, a magneton in the reaction kettle is driven to rotate by an external magnetic field which is provided by a magnetic stirrer in a magnetic stirring system, and gaseous and liquid phases in the reaction kettle are stirred.

The invention provides a disturbance magnetic field compensation method, specifically a disturbance magnetic field compensation method when the tracking compensation sensor is in the non-working area of ​​the magnetic field coil, which can eliminate the difference in the coil constant of the primary compensation winding caused by the increase of the distance. The method is based on the conventional interference magnetic field compensation system, adding a secondary compensation winding at the position of the sensor for tracking compensation, so that the magnetic field coil constant of the primary compensation winding at the position of the sensor for tracking compensation in the interference magnetic field compensation system is the same as that of the sensor under test. The magnetic field coil constants at the positions are equal, and this method can eliminate the difference in the magnetic field coil constants of the primary compensation winding caused by the inconsistency between the compensation sensor and the measured object, so that the interference magnetic field compensation system can achieve the best compensation effect.

A camera module is provided, comprising: a mover mounted with a lens; a stator supporting the mover to an optical direction of the lens; a side actuator mounted with a coil and a magnet moving the mover to the optical direction relative to the stator; a ball interposed between the mover and the stator; and coils, each coil provided at the mover and the stator to guide a linear travel of the ball, wherein the side actuator is lopsidedly arranged at each one side of the stator and the mover.

The invention discloses a polymer solution-based magnetofluid self-assembly needle-free electro-spinning device which comprises a groove. The device further comprises a controllable magnetic field generation module, a high-voltage electric field generation device, a conductive fiber receiving device used for collecting cellosilk, and at least one conductive and magnetic conductive cone tower. The surface of the cone tower is provided with a threaded groove ascending spirally along the cone tower. The polymer solution-based magnetofluid self-assembly needle-free electro-spinning device is simple in structure, operation is controllable and easy to control, and processing efficiency is high. Meanwhile, the invention further provides a nanofiber electro-spinning method achieved through the needle-free electro-spinning device. According to the method, the aim of controlling jetting of polymer solution-based magnetofluid is achieved by controlling electric and magnetic fields. The method is controllable, easy to control and good in control accuracy.

The invention discloses a parallel IGBT power unit. The parallel IGBT power unit comprises an upper bridge IGBT module and a lower bridge IGBT module. Each IGBT module includes at least two IGBT modules which are connected in parallel, and further comprises an upper busbar and a lower busbar which are correspondingly connected with the two IGBT modules. The upper busbar is provided with a first leading-out terminal for connecting with a first main busbar and a first capacitor connecting terminal for connecting with a capacitor. The lower busbar is provided with a second leading-out terminal for connecting with a second main busbar and a second capacitor connecting terminal for connecting with a capacitor. According to the parallel IGBT power unit, the two IGBT modules and the two busbars which have identical structures and are correspondingly connected with the modules respectively are adopted; the leading-out terminals for connecting with the main busbars and the capacitor connecting terminals for connecting with the capacitors on the busbars are in conductive connection with docking connecting terminals and capacitor connecting terminals at corresponding positions of the IGBT modules of corresponding busbars by using copper bars in identical lengths; and since busbars connecting the IGBTs are identical in length, the current-sharing performance of the parallel IGBT modules on the busbars is guaranteed, and a problem of uneven current during parallel connection of the IGBTs is solved.