210results about How to "Prevent internal leakage" patented technology

A method and device for transforming data with a secret parameter in an elliptic curve cryptosystem based on an elliptic curve defined over an underlying prime field, includes multiplying a point of the elliptic curve; representing the data to be transformed, by a scalar representing the secret parameter, wherein the multiplying includes performing at least one point addition operation and at least one point doubling operation on points of the elliptic curve; providing a representation in affine coordinates of the elliptic curve point to be multiplied and a representation in projective coordinates of intermediate elliptic curve points obtained during the multiplying; performing both the point addition operation and the point doubling operation by means of a sequence of elementary prime field operation types, the elementary prime field operation types including: a first type of prime field operations including field multiplication and field squaring of coordinates of the elliptic curve points and a second type of prime field operations including field addition, field doubling, and field subtraction of coordinates of the elliptic curve points.

The invention presents a MONOBLOC fin and plate heat exchanger design preventing internal leakages and intermixing of high-temperature and low-temperature flows, e.g. oil and fuel. This is achieved through a particular configuration of the heat exchanger, whereby its core assembly is completely or partially produced from a one-piece monolithic metallic block. Owing to that, all brazed seams, which in conventional fin and plate heat exchangers contact with both hot medium and cold medium flows, are fully abolished thereby excluding a source for imperfections usually developing in brazed joints and base metal in the process of pressure-temperature cyclic loading. Employing custom-made individual fins allows about two-fold increase in the strength of brazed joints in comparison with ordinary corrugated fins (due to doubling of the brazed surface). As a result, the suggested configuration allows the design of a high reliability compact heat transfer device for much higher operating pressures than what may be achieved in the conventional fin and plate heat exchanger. This invention may be used in different fields of modern technology, especially for aeronautical engine applications, where the challenge of ensuring reliability levels of one failure in millions of (fleet-cumulative) flight hours, and operating pressure levels of thousands of pounds per square inch, must be met.

The invention discloses an electronic expansion valve. A sleeve (4) is fixed in a main valve cavity (11), a valve core seat (2) is movably arranged in the sleeve (4) axially, a sleeve runner (41) is arranged on the peripheral side wall of the sleeve (4), and a valve core seat side hole (24) is formed in the peripheral side wall of the valve core seat (2). When a refrigerant is in forward flowing, the valve core seat (2) closes a main valve port (441) to break off communication between the sleeve runner (41) and the valve core seat side hole (24), and the refrigerant flows to a valve core valve port (21) through the sleeve runner (41); when the refrigerant is in backward flowing, the valve core seat (2) is moved upwards to open the main valve port (441) to communicated the valve core seat side hole (24) with the sleeve runner (41); when the refrigerant is in forward flowing, by the structural design of the electronic expansion valve, high-pressure refrigerant can be avoided from causing overlarge impact on the valve core seat, and eccentric phenomena of the valve core seat can be prevented.

A scaffold for the artificial blood vessel without internal leakage and curved easily is composed of multiple Z-shaped rings arranged axially. Several connecting rods are connected between two Z-shaped rings. The top and bottom Z-shaped rings have archor rods. A segment of sealed artificial blood vessel wall is arranged at both ends of said scaffold. The middle segment of artificial blood vessel wall is linked to said sealed ones in sleeve mode.

The invention discloses an aorta covered stent with a chimney stent supporting pipe. The aorta covered stent comprises a main stent, at least one supporting pipe for releasing a chimney stent is arranged in the main stent, arranged close to the front end of the main stent and tightly and fixedly connected with the inner wall of the main stent, and the wall of the main stent is provided with a through hole communicated with the supporting pipe. By means of the aorta covered stent of the structure, the at least one supporting pipe is reserved in the aorta covered stent, after the aorta covered stent is released and attached to the wall, the chimney stent is then released by the reserved supporting pipe into important branch blood vessels, and blood flow supplying to the important branch blood vessels is accordingly guaranteed. Due to the fact that the chimney stent is released to the inner side of the aorta covered stent, wall attaching of the aorta covered stent cannot be influenced, and inner leakage can be accordingly and effectively avoided; in addition, the aorta covered stent cannot press the chimney stent, and decreasing of cross sections of blood flow channels or blocking of the blood flow channels formed by the chimney stent can be effectively avoided.

The invention relates to a small underwater cable cutting device which comprises an oil cylinder barrel, wherein a piston rod is mounted inside the oil cylinder barrel; a movable cutting knife is connected with one end part of the piston rod through a shaft pin and a set screw; a guiding frame is connected with one end of the oil cylinder barrel; after extending out of the guiding frame, the movable cutting knife is matched with a fixed cutting knife to cut off a cable; the fixed cutting knife is mounted on the bottom surface of the guiding frame; two limiting frames are correspondingly mounted on the upper surface of the guiding frame and the lower surface of the fixed cutting knife; one end of the upper limiting frame and that of the lower limiting frame are simultaneously connected witha vertically-mounted gasket; the movable cutting knife and the fixed cutting knife are positioned between the two limiting frame; and the gasket is positioned between the movable cutting knife and the fixed cutting knife. By the adoption of the small underwater cable cutting device provided by the invention, the technical problem that a conventional underwater cutting device is complex in structure, large in weight and occupied space, high in operating difficulty and low in autonomous operability can be solved; the space can be greatly saved; and the underwater cutting efficiency can be improved.

The invention discloses a fuel cell, and a bipolar plate and a bipolar plate assembly for the fuel cell. The bipolar plate comprises at least one distribution unit; at least one first through hole connected with the corresponding distribution unit through a transverse opening in the side wall of the at least one first through hole so that a first reactant can flow into the at least one first through hole; and at least one second through hole connected with the corresponding distribution unit through a transverse opening in the side wall thereof so as to flow out the first reactant, wherein thecross sections of the at least one first through hole and the at least one second through hole are approximately arc-edge trapezoids or bevel-edge trapezoids in shape, and transverse openings are formed in the curved-surface side wall or bevel-surface side wall. According to the fuel cell, by improving the structural design of the bipolar plate, the gas distribution uniformity of the fuel cell can be improved, and the hydrothermal management is improved, so that the high-current discharge performance and the power density of the fuel cell are improved. In an electric vehicle, the power performance, the fuel utilization efficiency and the endurance mileage of the vehicle can be improved.

The invention discloses an aortic windowing branch covered stent and belongs to the technical field of vascular stents. The aortic windowing branch covered stent comprises a tubular skeleton made of thin filaments and a membrane covering the tubular skeleton. The proximal end of the tubular skeleton is suitable for being inserted into a window of the aortic windowing branch covered stent and communicated with the aortic windowing branch covered stent. The remote end of the tubular skeleton is suitable for being inserted into a branch blood vessel, and the proximal end is harder than the remote end. The aortic windowing branch covered stent lowers the operation difficulty of minimally invasive surgery in an aortic lumen with branch blood flow, solves the technical problem that in the surgery, internal leakage occurs easily, can adapt to fitting the tortuous branch blood vessel and effectively prevents damage to the branch blood vessel and occurrence of re-blocking and internal leakage.

The invention relates to a middle sealing sand filling technology capable of preventing inner leakage of investment casting. The technology specially comprises the following steps that silica solutionand zircon powder coating is adopted for a face layer of a wax module, and 120-mesh zircon sand is spread; 2, silica solution and zircon powder coating is adopted for a second layer, and 30-60-mesh mullite sand is spread; 3, silica solution and mullite powder coating is adopted for a third layer, and 30-60-mesh mullite sand is spread, 4, silica solution and mullite powder coating is adopted for afourth layer, only hanging coating is adopted for coating, no sand is spread, a hole is filled with sand after drying, and a hole opening is sealed; and 5, silica solution and zircon powder coating is adopted for follow-up layers, 16-30-mesh mullite sand is spread till requirements are met, and no sand is spread in the last layer. According to the middle sealing sand filling technology, the strength of a deep blind hole and a narrow deep groove of a mold shell can be improved, inner leakage at the positions can be effectively prevented, the inner leakage rate of small holes is reduced from the original 10% to 2% or below after adopting the method through tests, and the effect is obvious.

Methods for ameliorating stent graft migration and endoleak using treatment site-specific cell growth promoting compositions in combination with stent grafts are disclosed. Also disclosed are application of cell growth promoting compositions such as, but not limited to, autologous platelet gel compositions directly to treatment sites before, during or after stent graft implantation. Additional embodiments include medical devices having autologous platelet gel coatings and/or autologous platelet gel delivery devices useful for treating aneurysms.

The invention discloses a valve, in particular to a nuclear second-stage electric V-shaped brake valve comprising a valve rod and an electric device which can drive the valve rod to reciprocate on a straight line, wherein the bottom end of the lower part of the valve rod is fixedly connected with a flashboard subassembly which comprises a flashboard frame, a left flashboard, a right flashboard, a valve seat, a spring and a locating rack, the bottom end of the lower part of the valve rod is also fixedly connected with the flashboard frame, the left flashboard and the right flashboard are clamped in the flashboard frame and are also fixed in the flashboard frame by the locating rack, and a cavity which is provided with a horizontal compression spring is formed between the inner walls of the left flashboard and the right flashboard; the bottom of the flashboard frame is matched with a spacing lug boss of a valve body, and the side wall of the flashboard frame is provided with a groove which can be matched with a guide lug boss of the valve body; a left cavity and a right cavity are formed on the valve body by the flashboard subassembly; the locating rack, the flashboard frame and the valve rod are mutually fixedly connected; the valve seat is arranged between the outer wall of each flashboard and the valve body, and the other side of the valve seat is welded with the valve body. The nuclear second-stage electric V-shaped brake valve has good sealing property, reasonable structure and simple, easy and convenient installation.

The invention discloses a plunger water pump. The plunger water pump provided by the invention comprises two plunger groups which are composed of water cylinders and oil cylinders, a water cylinder piston and an oil cylinder piston of each plunger group are synchronously displaced, a water gap of each water cylinder barrel is provided with a water inlet one-way valve which is in one-way conduction with a cylinder tube cavity from the outside and a water outlet one-way valve which is in one-way conduction with the cylinder tube cavity from the cylinder tube cavity to the outside; and two oil cylinders are alternately stretched under the control of a control valve. The plunger water pump provided by the invention breaks through a traditional water pump structural principle, two oil cylinders are adopted to alternately move and retreat, thereby driving two water cylinders pistons to alternately move, and further the switch of two working conditions is respectively realized; compared with the prior art, the plunger water pump is capable of effectively improving the output flow and the water utilization pressure on the basis of the continuous no-interval foundation; and the invention also provides a liquid control system of the plunger water pump.

The invention discloses a positioning and locking device for a ball valve. The positioning and locking device comprises a limiting post fixed to a valve cover and a limiting disk fixed to a valve rod, wherein the limiting disk is provided with a limiting gap or a limiting groove; the limiting post is positioned in the limiting gap or the limiting groove; a locking block is rotationally arranged on the limiting post; the upper end face of the locking block is lower than the lower end face of the limiting disk; the locking block is provided with a dynamic locking hole; the limiting disk is provided with a static locking hole matched with the locking fixing hole; the dynamic locking hole and the static locking hole are matched with each other, and can be locked through a locking piece. By adopting the positioning and locking device, the opening or closing state of the ball valve can be positioned, and the ball valve can be locked, so that the accuracy of the ball valve is ensured, and internal leakage is avoided.

The invention discloses a closed type open commutator which comprises a control box provided with a component for supplying power for commutation, a rotating disk which is positioned below the control box and is provided with a plurality of nozzles, a floating disk which is matched with the rotating disk and is provided with diversion holes corresponding to the nozzles, and a water feeding pipe positioned at the center of the open commutator, wherein a diversion cone is arranged above the water feeding pipe. The commutator disclosed by the invention has a steady commutation process and is high in symmetry and repetitiveness; the flowing state of fluid is stable and symmetric as much as possible at outlets of the nozzles; water sputtering and internal leakage of the commutator are avoided, and interference caused by the commutation process on the flow of a flow device system is also avoided.

The invention provides a heat pump air-conditioning system and a control method for avoiding inner leakage of the heat pump air-conditioning system. The heat pump air-conditioning system comprises a compressor, a plate type heat exchanger communicated with the air suction inlet of the compressor through a refrigerant pipe, a first valve connected to a refrigerant inlet pipe of the heat exchanger, a second valve connected to a refrigerant outlet pipe of the heat exchanger, a first pressure sensor arranged between the first valve and the refrigerant inlet of the heat exchanger, and a controller which can transmit control signals to control the on and off of the compressor, the first valve and the second valve according to the comparing result of the sensed pressure of the first pressure sensor and the saturation pressure of refrigerant. By controlling the on and off of the two valves, the inner leakage of the plate type heat exchanger can be effectively avoided and further corrosion of cooling water to other parts due to the inner leakage can be avoided, so that the losses due to inner leakage of the heat exchanger can be reduced.

The invention relates to a boiler roof sealing device and method, in particular to a method for sealing the body of a power station boiler. the method comprises the following steps of: treating a working surface; fixing sealing dead points; paving a ceramic fiber layer; and paving a diamond stainless steel mesh. The invention also provides a boiler roof sealing device which comprises the ceramic fiber layer and the stainless steel mesh, wherein the ceramic fiber layer is paved on the working surface on which forms expansion difference measurement points among vertical and horizontal wall pipes of the body of the boiler, the stainless steel mesh is arranged on the surface of the ceramic fiber layer, the ceramic fiber layer and the stainless steel mesh are fixed by welding stainless steel nails, the stainless steel nails are arranged on the horizontal working surface in a staggered manner, stainless steel wires are tied to the vertical wall pipes, the welding positions of the stainless steel nails and the tying positions of the stainless steel wires are horizontal sealing dead points and vertical sealing dead points respectively, the area defined by the horizontal sealing dead points is named a horizontal sealing dead point area, the area defined by the vertical sealing dead points is named a vertical sealing dead point area, and the expansion difference measurement points are arranged at the centers of the horizontal sealing dead point area and the vertical sealing dead point area.

The invention provides a quantum security direct information communication method and system based on three degrees of freedom, and belongs to the technical field of quantum communication. A server prepares a super-entangled quantum state, forms a first sequence by using first photons in each Bell state to serve as an information carrier, and sequentially transmits the information carrier to a first user terminal, a second user terminal and a third user terminal. The first user terminal, the second user terminal and the third user terminal finally send back the first sequence to the server through encoding operations with three degrees of freedom in the first sequence respectively. The server can deduce the encoding modes of the first user terminal, the second user terminal and the third user terminal on each degree of freedom by performing super-entangled Bell state measurement on two sequences, in order to collect information. As the security is guaranteed by the non-local correlation features of the quantum entangled state, an eavesdropper can only steal a part of an entangled particle system at a time but cannot obtain the overall state of the quantum entanglement pair, therebyensuring that the information is not leaked.

This invention relates to one wheel anti-explosion hydraulic brake, which comprises wheel brake rack and Pump hydraulic system and control device, wherein, the pump cylinder hydraulic system comprises hydraulic pump, single oil cylinder, overflow valve, anti-explosion magnetic valve, single valve, pressure meter switch, proportion flow save valve, proportion pressure valve, anti-explosion motor, filter, cylinder oil case with air filter and system oil case; the control device comprises transducer, breaker, alternating touch device, heat relay, leakage protector, direct drive power, programmable controller, local isolation grating and point button and non-touch near switch.

The invention discloses a collector plate of a vanadium redox battery and a preparation method thereof, and the collector plate of the vanadium redox battery has the characteristic of improving the charging and discharging performances; the collector plate of the vanadium redox battery comprises an electricity-conduction plastic body which is formed by distributing a plurality of electricity-conduction plastic strips at interval, a flow field plate is arranged between the two adjacent electricity-conduction plastic strips, and the height of the electricity-conduction plastic strips and the height of the flow field plate are unequal to form an electrolyte solution groove; the preparation method is that: a. electricity-conduction fillers are added in a thermoplasticity polymer to obtain thermoplasticity electricity-conduction plastic strips; b. the electricity-conduction plastic strips are arranged and fixed at interval; c. epoxide resin or phenolic resin for forming the flow field plate is cast among the electricity-conduction plastic strips; d. solidification. When the electrolyte solution flows in the electrolyte solution groove, the flowing is unobstructed, and the battery polarization is low; the vanadium redox battery arranged in the collector plate has good charging and discharging performances, thereby being popularized and applied to the vanadium redox battery.

The invention discloses a stop valve and an air conditioner with the stop valve. The stop valve comprises a valve seat, a lantern ring, a valve spool and an elastic sealing element, wherein a valve chamber and a fitting chamber communicated with the valve chamber are defined in the valve seat, the fitting chamber is located on the first end surface of the valve chamber and the valve chamber is further provided with two openings communicated therewith; the lantern ring internally sleeves one opening; the valve spool comprises a fitting part and a stop part arranged on the fitting part, the fitting part in in threaded fit with the fitting chamber, the stop part is located in the valve chamber and is in threaded fit with the valve chamber, and the stop part is in contact with the first end surface of the lantern ring to connect/disconnect the two openings; the elastic sealing element is arranged on the end surface, towards the lantern ring, of the stop part, and the elastic sealing element is in contact with the end surface of the lantern ring to disconnect the two openings. The stop valve disclosed by the invention has the advantages that the locking torque is reduced to a certain extent, the wear of the sealing surface between the lantern ring and the valve spool is avoided, the internal leakage of the stop valve is avoided, the service life of the stop valve is prolonged and the maintenance rate of the stop valve is reduced.

The invention relates to a valve needle assembly and an electronic expansion valve with the valve needle assembly. In one aspect, the invention provides the valve needle assembly. The valve needle assembly comprises a valve rod, a valve needle, an elastic element and a stop structure; the valve needle is connected to the valve rod and can move in the axial direction relative to the valve rod; theelastic element is arranged between the valve rod and the valve needle; and the stop structure is configured to limit the axial movement of the valve needle relative to the valve rod so as to preventthe valve needle from opening a valve port of the electronic expansion valve in advance under the acting force of fluid. In another aspect, the invention provides the electronic expansion valve. The electronic expansion valve comprises the valve needle assembly. According to the valve needle assembly and the electronic expansion valve, the phenomenon that internal leakage is caused due to the factthat the electronic expansion valve is opened in advance under the action of the fluid can be avoided, and the flow of the fluid flowing through the electronic expansion valve can be accurately controlled in a forward state and a reverse state; and in addition, the electronic expansion valve is provided with a balance passage, so that the stress of the valve needle assembly can be effectively balanced.

The invention discloses an integral light manual pump which comprises a steering wheel, a pump shaft, a pump body, plungers, an oil distribution shaft, a cylinder body and a rear cover. The pump body and the rear cover are matched to form a pump cavity. The pump shaft is arranged in the pump cavity. The left end of the pump shaft penetrates out of the pump cavity. The steering wheel is arranged at the left end of the pump shaft. The right end of the pump shaft is sleeved with the cylinder body. The pump shaft is in interference fit with the cylinder body. A plurality of plunger sleeves are arranged on the cylinder body. The front end of the oil distribution shaft is located in the cylinder body. The plungers are located in the plunger sleeves. A pump body oblique face is arranged in the pump body and is of a reinforcing rib structure. The pump body oblique face and the pump body are integrally formed through finish casting. The pump body oblique face is rotatably sleeved with a retainer plate. The front ends of the plungers are connected to the retainer plate. The pump body is made of aluminum alloy. The pump body of the integral light manual pump is made of aluminum alloy, and an original all-steel structure is replaced. The pump body oblique face is of the reinforcing rib structure, so that the weight is reduced. In addition, the pump body oblique face and the pump body are integrally formed through finish casting, the structure is compact, and the size is small.