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204 results about "Load rejection" patented technology

Load rejection in an electric power system is the condition in which there is a sudden load loss in the system which causes the generating equipment to be over-frequency. A load rejection test is part of commissioning for power systems to confirm that the system can withstand a sudden loss of load and return to normal operating conditions using its governor. Load banks are normally used for these tests.

Method for identifying practical parameters of synchronous generator on basis of load rejection test and numerical difference

The invention relates to a method for identifying practical parameters of a synchronous generator on basis of a load rejection test and a numerical difference. The method comprises the following steps: utilizing a conventional method to confirm steady parameters of a generator; taking an exciting voltage after the load rejection test is performed as an input volume; taking a difference between a theoretical value of a machine-end voltage and a practically measured value under an evaluating system as a target function; and utilizing an iterative solution method for an extreme value of the target function based on a steepest descent method to realize the identification for the parameters of the generator, wherein a numerical difference method is used for obtaining the gradient of the target function during an iterative process and a difference value of adjacent twice target functions and the gradient of the target function are taken as control conditions for ending the iteration. The load rejection test, on which the identification is based, is easily realized; a high enough induction current can be generated in a damping winding after the load rejection test is performed; the machine-end voltage is obviously changed during the temporary state process and the sub-temporary state process; the interference of environmental noise to the identification for a time domain is efficiently overcome; and the problem of unsteady indentifying result is solved.
Owner:CHINA ELECTRIC POWER RES INST +1

Full sea depth small self-floating type straight-through impact sampling device

The invention provides a full sea depth small self-floating type straight-through impact sampling device, which includes an upper release self-floating mechanism and a lower load rejection counterweight mechanism. The release self-floating mechanism includes a flat cylindrical buoyancy block, the circumference of which is uniformly provided with at least two sleeves extending downward vertically. A fixation seat is fixedly connected to a place below the center of the buoyancy block, the part below the fixation seat is fixedly connected to at least one clamping sleeve, and a sampling tube is connected below the clamping sleeve. A buffer spring is arranged between the sampling tube and the clamping sleeve top wall. The load rejection counterweight mechanism comprises a load rejection counterweight block, and a guide stabilizing column is arranged above the load rejection counterweight block. And a mechanical release mechanism is disposed below the center of the fixation seat. The impact sampling device provided by the invention solves the problems of difficult carrying, complex structure, expensive cost and the like in existing seafloor samplers. After sampling, the load rejection counterweight block floats upward independently, additional power and stranded cable are not needed, 2-3 people can finish the all launching and retrieval process, and the device has the characteristics of simple and reliable structure, and convenient maintenance.
Owner:NAT DEEP SEA CENT

Lock-opening style underwater load rejection mechanism

The invention discloses a lock-opening style underwater load rejection mechanism comprising a motor module, a guide sleeve module and a lock module, wherein the motor module comprises a motor, and the motor is fixed on a sealing end cover through a motor fixing block provided with a sliding chute; the sealing end cover is provided with a hole and one end of the hole is covered by a sealing flange in which a lock-pushing shaft is inserted; and a motor rotating shaft is sleeved sequentially with a motor worm-wheel, a motor anti-rotating disk provided with a sliding block, and a thrust-shaft sleeve provided with a claw at one end thereof, wherein the motor worm-wheel, the motor anti-rotating disk and the thrust-shaft sleeve are fixedly connected; and the guide sleeve module comprises a releasing ejector plate and a guide plate; two ends between the releasing ejector plate and the guide plate are respectively connected with guide rods; the lock module comprises a fixing wallboard connected with a ratchet wheel and a pawl, wherein the pawl is connected with a load to be rejected; and the guide sleeve module and the lock module are respectively connected with the sealing end cover through a guiding device. The lock-opening style underwater load rejection mechanism has small volume, light weight and high reliability.
Owner:TIANJIN UNIV

Diving slamming experimentation device for ocean structure

ActiveCN104697737AMeet the needs of water slamming simulationSimple structureShock testingLower limitLoad rejection
The invention discloses a diving slamming experimentation device for an ocean structure. The diving slamming experimentation device for the ocean structure comprises the structure, a power system, a load rejection system, a control and measurement system, a buffer system and a substrate, the power system mainly comprises a motor seat, a screw rod, a vertical lead rail, an optical axis and a screw rod; the load rejection system comprises a primary load rejection carriage, a secondary load rejection carriage, an electromagnet and a slide block; the control and measurement system mainly comprises a computer, a data gatherer, a constant-voltage direct current power supply, and an upper and a lower limit switch, the buffer system comprises a buffer substrate, a spring bumper and a buffer platform, the control and measurement system controls through motor motion and magnetic force of the electromagnet to realize primary load rejection and secondary load rejection, the structure falls into the water, and a pressure sensor arranged on the structure returns the measured data to the computer through the data gatherer. The diving slamming experimentation device for the ocean structure is simple in structure, convenient to operate, stable in move and suitable for the diving slamming experiments for different types of ocean structures.
Owner:HARBIN ENG UNIV

Hybrid drive type underwater glider with various working modes

The invention belongs to the field of marine observation associated equipment and discloses a hybrid drive type underwater glider with various working modes. The hybrid drive type underwater glider comprises a shell, horizontal wings, a combination planar antenna, a vertical tail vane, an observation instrument, a fixed battery pack, a mass center adjusting device, a buoyancy adjusting device, anemergency load rejection device and a pump jetting propelling device, wherein the horizontal wings, the combination planar antenna and the vertical tail vane are installed on the outer portion of theshell, the observation instrument, the fixed battery pack, the mass center adjusting device, the buoyancy adjusting device, the emergency load rejection device and the pump jetting propelling device are installed in the shell, and meanwhile, according to the modularized design concept, the shell is designed to be provided with a stem loading cabin, an energy cabin, an attitude adjusting cabin, a buoyancy adjusting cabin and a stern maneuvering cabin. The hybrid drive type underwater glider has the beneficial effects of being low in power consumption, long in cruising range, long in endurance and the like, the flow resisting capacity is remarkably improved, various motion modes are provided, high-accuracy emergency load rejection can be executed, and therefore a target sea area can be observed in a large range and with high accuracy.
Owner:HUAZHONG UNIV OF SCI & TECH

Method and system for obtaining parameters of synchronous generator

The invention provides a method and system for obtaining parameters of a synchronous generator. The method comprises the following steps of: respectively creating corresponding simulation models according to test data of a no-load characteristic test, a no-load de-excitation test, a D-axis load rejection test and a Q-axis load rejection test; fitting rotor voltage data and rotor current data in the data of the no-load characteristic test of a generator to generate a saturation characteristic curve so as to modify stator voltage data, the rotor voltage data and the rotor current data of the test data of the no-load characteristic test, the no-load de-excitation test, the D-axis load rejection test and the Q-axis load rejection test and then generating a stator voltage test waveform; inputting generator default parameters and the modified rotor voltage data and rotor current data in the test data into the simulation models; and modifying the simulation waveform according to the stator voltage test waveform, and outputting an instant time constant, D-axis parameters and Q-axis parameters. The invention fully considers the influences of nonlinear factors of saturation, vortex and the like, improves the accuracy of the parameters and provides reliable technical evidence for the transient stability calculation and dynamic stability calculation of a power system.
Owner:NORTH CHINA ELECTRICAL POWER RES INST +2

Emergency load rejection and position indicating device and method of unmanned underwater vehicle

The invention provides an emergency load rejection and position indicating device of an unmanned underwater vehicle. The emergency load rejection and position indicating device of the unmanned underwater vehicle comprises an emergency load rejection unit with a counterweight. A position indicating unit is arranged below the counterweight. The counterweight is located between the underwater vehicle and the position indicating unit. The position indicating unit comprises a floating body. The floating body is internally provided with a communication positioning antenna, a control unit, a battery and a water depth pressure sensor. The underwater vehicle, the counterweight and the floating body are connected through explosive bolts. The explosive bolts movably penetrate through through holes in the counterweight and then are fixedly connected with the floating body. The control unit comprises a single chip microcomputer, a communication positioning module and a control circuit. A communication cable is arranged between the single chip microcomputer and the communication positioning module. A transmission wire is arranged between the water depth pressure sensor and the single chip microcomputer. The single chip microcomputer controls ignition of the explosive bolts through the control circuit. The communication positioning antenna is connected with the communication positioning module through a feedback line. Power is supplied to the position indicating unit through the battery. The invention further provides a corresponding emergency load rejection and position indicating method. According to the emergency load rejection and position indicating device and method of the unmanned underwater vehicle, the dual functions of emergency load rejection and position indicating can be achieved, and the searching efficiency and the success rate are improved.
Owner:中国船舶重工集团公司第七〇二研究所

Emergency load rejection mechanism of deep-sea manned submersible

Provided is an emergency load rejection mechanism of a deep-sea manned submersible. The emergency load rejection mechanism of the deep-sea manned submersible comprises a rotary shaft, wherein the rotary shaft penetrates through a pressure-resistant spherical shell cabin, a hand lever is inserted into the upper end of the rotary shaft, the middle of the rotary shaft is installed in a shaft sleeve through a shaft sealing device, the shaft sleeve is arranged under the pressure-resistant spherical shell cabin, a ballast hanging protruding claw wheel is installed at the lower end of the rotary shaft, the ballast hanging protruding claw wheel is inserted into a hole in the top surface of a ballast block, and hanging is achieved; two guiding slide ways are formed in each of the four vertical planes of the ballast block so that the ballast block can be smoothly rejected under the conditions of different inclined postures of the deep-sea manned submersible. According to the emergency load rejection mechanism of the deep-sea manned submersible, an operator directly rotates the T-shaped hand lever to reject the emergency ballast block so that the deep-sea manned submersible can obtain enough buoyancy to upwards float to the water surface in emergency, the problem that when a control system has a failure, a submersible cannot reject ballast block to upwards float is solved, and it is ensured that the manned submersible can return safely.
Owner:CHINA NAT OFFSHORE OIL CORP +2

Load rejection type deep sea oceanic turbulence mixing profile measuring instrument

The invention discloses a load rejection type deep sea oceanic turbulence mixing profile measuring instrument which comprises a recycling cabin and a load rejection cabin, wherein the load rejection cabin is arranged at the head part of the recycling cabin; the load rejection cabin comprises a load rejection releasing ring and a load rejection body; the load rejection body is connected with the recycling cabin through the load rejection releasing ring; a data measuring sensor is arranged on the load rejection body; a floater material block is arranged at the tail part of the recycling cabin; a positioning communication beacon is arranged on the floater material block; a main control unit, a data collecting unit and a posture control unit are arranged in the recycling cabin; the data collecting unit is connected with the data measuring sensor; the posture control unit is connected with the load rejection releasing ring; and the main control unit is respectively connected with the data collecting unit and the posture control unit. Without warping hawser, after being put into water, the load rejection type deep sea oceanic turbulence mixing profile measuring instrument can descend at a constant speed under the effect of gravity for observing, and the maximum working water depth of the instrument is 6000 meters, so that a new technical method is supplied for acquiring turbulence energy consumption and thermal dissipation data of deep sea areas and bottom boundary layers.
Owner:INST OF DEEP SEA SCI & ENG CHINESE ACADEMY OF SCI

Electromagnetic type emergency load rejection device for underwater glider

ActiveCN108609134AEnsure the safety of long-distance navigationCompact structureUnderwater vesselsUnderwater equipmentLoad rejectionConstant load
The invention belongs to the technical field of underwater vehicle related parts, and discloses an electromagnetic type emergency load rejection device for an underwater glider. The electromagnetic type emergency load rejection device comprises a mounting base, a stainless steel shaft, an iron core, an electromagnetic winding and a steel casing. The iron core is arranged in the lower end of the stainless steel shaft in an embedded mode, and then integrally installed in a groove cavity of the mounting base in a sleeved mode together with the stainless steel shaft, and the upper end of the stainless steel shaft is sealed by a sealing cover and a compression spring. In addition, an electromagnet element is formed in the formed sealed space, and the iron core is driven to move up and down in real time and efficiently through electromagnetic induction when energized, so that the stainless steel shaft is driven to be removed from the mounting base to enable a load rejection block on the stainless steel shaft to be released in an emergency. Through the electromagnetic type emergency load rejection device for the underwater glider, the straight driving principle and the internal and external pressure balancing mechanism can be utilized comprehensively, the constant load rejection driving force can be obtained under the premise of significantly reducing the transmission link, and at thesame time, the characteristics of no need for dynamic seal, easy operation and control, low maintenance complexity and high reliability are achieved.
Owner:HUAZHONG UNIV OF SCI & TECH

Training mine for simulating actual anti-mine training

The invention discloses a training mine for simulating actual anti-mine training. The training mine is characterized in that a training mine body comprises a housing, a fuse unit, a position indication unit, a power supply module, a balancing weight and a control unit, wherein the fuse unit, the power supply module, the balancing weight and the control unit are all fixedly mounted in the housing; the position indication unit is arranged at the upper end of the outside of the housing, and a connecting ring is arranged at the lower end of the outside of the housing; a mooring system comprises a connecting mooring system and a load rejection mooring system; a swivel of the connecting mooring system is connected to the connecting ring at the lower end of the outside of the pressure-resistant housing, one end of a chemical fiber rope is connected with the rotary ring through a shackle, and the other end of the chemical fiber rope is connected with an acoustic release transponder through a shackle; the front end of an anchor chain of the load rejection mooring system is connected with the acoustic release transponder through a shackle, the rear end of the anchor chain of the load rejection mooring system is connected with a ballast anchor through an inactive rope, and a floating ball and a pouring weight are sequentially connected to the anchor chain; the position indication unit consists of a communication module, a module housing and an antenna, and the communication module is connected with the power supply module in the training mine body through a wire; and the antenna is assembled at the upper part of the module housing.
Owner:CSIC NO 710 RES & DEV INST

System and method for location communication and monitoring emergency control for underwater robot

The present invention relates to a system and method for location communication and monitoring emergency control for an underwater robot. One end of a location communication device is connected with a GPS location device, a radio communication device is connected with a satellite communication device, the other end of the location communication device is connected with an automatic driving unit through a wireless network bridge device, one end of a monitoring module is connected with an automatic driving unit through a CAN bus, the other end of the monitoring module is connected with a depth/height device, a water leakage detection device, a pressure switching device and a location display light beacon device, one end of an emergency processing module is connected with the automatic driving unit through the CAN bus, and the other end of the emergency processing module is connected with a load rejection device and an emergency battery device. The system and method for location communication and monitoring emergency control for the underwater robot integrally use the sensor communication device carried by the underwater robot for time-share work so as to ensure the rapid and reliable communication of the underwater robot with the water surface console after going out of the water surface; and moreover, the system and method perform uniform management of each observation device through the underwater robot and perform effective monitoring of each control node through the underwater robot to realize the optimal utilization of the energy carried by the underwater robot.
Owner:SHENYANG INST OF AUTOMATION - CHINESE ACAD OF SCI

Fuse-type load rejection device for underwater equipment and control method thereof

The invention relates to a fuse-type load rejection device for underwater equipment and a control method thereof. The device comprises a fuse-type load rejection device control unit in an underwater equipment bay and a load rejection device sealing connecting piece outside the equipment bay, wherein the load rejection device control unit and the load rejection device sealing connecting piece are electrically connected by a conducting wire; the load rejection device sealing connecting piece is provided with a first terminal, a second terminal, insulating sealing fillers, a first low-resistance connection pin, a second low-resistance connection pin and an alloy resistance wire, wherein the first low-resistance connection pin and the second low-resistance connection pin penetrate through a cavity body of a sealing fixing piece; one ends of the low-resistance connection pins are respectively and electrically connected with the terminals which are arranged at the end part of the sealing fixing piece, and the other ends pass through a short circuit arranged outside the sealing fixing piece; the cavity body of the sealing fixing piece is filled with the insulating sealing fillers; and the alloy resistance wire is connected with a ballast weight by a high-strength nonmetal connecting line. The device of the invention does not have any movement mechanism or movement in a load rejection process, is not corroded by seawater or affected by biological contaminants, and has the advantages of low working voltage, safety, reliability and flexible quality of the ballast weight.
Owner:SHENYANG INST OF AUTOMATION - CHINESE ACAD OF SCI

Deep sea self-induction emergency load rejection mechanism

The invention provides a deep sea self-induction emergency load rejection mechanism. The mechanism comprises a ballast, wherein a lifting lug is fixedly arranged at the upper part of the ballast; an installation rack is fixedly installed on a subsea equipment body and comprises lug plates; through holes for passing and sliding of a plunger are formed in the lifting lug and the lug plates; a cylinder block is fixedly installed on the installation rack and is provided with a hollow cavity with an opening in one end; one end of the plunger is stuffed in the hollow cavity; the plunger and the hollow cavity are sealed by sealing elements; the sealed hollow cavity is pre-filled with internal pressure; the cylinder block and the plunger are connected by a locating pin; the other end of the plunger passes through the through hole of the lifting lug and the through holes of the lug plates; under the actions of the internal and external pressures of the sealed hollow cavity, the plunger is connected with the through hole of the lifting lug or breaks away from the through hole of the lifting lug so that the ballast is connected with the installation rack or breaks away from the installation rack. The mechanism achieves automatic load rejection through self induction of internal and external pressures.
Owner:CHINA SHIP SCIENTIFIC RESEARCH CENTER (THE 702 INSTITUTE OF CHINA SHIPBUILDING INDUSTRY CORPORATION)

Drifting detection underwater robot device and control method

The invention discloses a drifting detection underwater robot device and a control method, and belongs to the technical field of detection underwater robots. A robot main body is of a torpedo-shaped structure; hydrologic detection equipment ADCP (Acoustic Doppler Current Profiler), ranging sonar and an emergency load rejection device are carried at the fore body of a robot; a pressure-resistant cabin is arranged at a middle cabin section; the pressure-resistant cabin is divided into an energy source cabin and a control cabin; two high-energy density lithium batteries are arranged in the energysource cabin and are correspondingly used for supplying power to a power system and a control system; a conformal antenna (comprising Beidou positioning and communication, radio and WiFi), DVL, a depthometer and ranging sonar are carried at the tail section; high-efficiency propellers are arranged on the left side and the right side of the tail of the robot; and vertical channel propeller is arranged at each of the front and rear of the robot. According to the surrounding environment and task instructions of the robot, the effect of selecting to start or close a drifting mode is intelligentlyrealized, so that low-power-consumption, long-voyage and long-time detection monitoring tasks are realized.
Owner:HARBIN ENG UNIV

Full-sea-depth multi-purpose smart fishing device and control method thereof

ActiveCN107846580AAvoid damageOvercome the disadvantages that cannot be achievedProgramme controlComputer controlLoad rejectionAutomatic control
The invention discloses a full-sea-depth multi-purpose smart fishing device and a control method thereof. The smart fishing device comprises a separated fish cage, a buoyancy block component, a load rejection mechanism and a Beidou position indicator, wherein the Beidou position indicator is fixed at the top of the buoyancy block component, the buoyancy block component is arranged at the top of the separated fish cage, the load rejection mechanism is arranged at the bottom of the separated fish cage, the separated fish cage consists of two mutually independent fishing areas, each fishing areais fixed with a fish cage door, and a glass control cabin can control the corresponding fish cage doors according to the fishing conditions in each fishing area. According to the scheme of the invention, the fishing device is controlled to perform full-sea-depth smart fishing by using image identification and automatic control technologies, the depth of movement of the fish can be clearly positioned, and a deep sea fishing process can be recorded; and the scheme of the invention is suitable for cableless fishing operations with full-sea-depth characteristics, and overcomes the shortcoming thattraditional fishing methods are almost impossible to be realized in a full-sea-depth range.
Owner:SHANGHAI OCEAN UNIV

Modular fixed-point profile buoy

The invention relates to the field of marine environment monitoring, and in particular to a modular fixed-point profile buoy that comprises sensor modules which are sequentially connected and mutuallyindependent inside, a buoyancy material module, an electric control module, a buoyancy driving module and a power supply module; an emergency load rejection module is arranged on one side of the power supply module; an anchoring module is arranged at the lower end of the power supply module; a buoyancy adjusting mechanism is arranged in the buoyancy driving module; the buoyancy adjusting mechanism comprises a buoyancy adjusting clear water cabin and a buoyancy adjusting seawater cabin which are separated through an isolating membrane; clear water and a piston capable of moving in a reciprocating mode are arranged in the buoyancy adjusting clear water cabin; a through hole is formed in the buoyancy adjusting seawater cabin, and in addition, a plurality of hollow holes are formed in the lower end of a shell of the buoyancy driving module. The modular fixed-point profile buoy comprises a plurality of independent module units, different operation requirements can be met, the buoyancy adjusting structure is simple, the buoy cost is greatly reduced, and in addition, the anchoring module with a force unloading ring is further arranged, so that long-term fixed-point monitoring is achieved.
Owner:SHANGHAI OCEAN UNIV

Deep-sea structure release and load rejection system

ActiveCN108238222ALoad dump delayPrevent misloadingUnderwater equipmentLoad rejectionBallast
The invention relates to a deep-sea structure release and load rejection system. An acoustic release transponder and an automatic unhooking device are respectively arranged on a deep-sea structure frame; a set of load rejection actuating mechanism is arranged on each of two sides below the automatic unhooking device; each set of load rejection actuating mechanism comprises a long load rejection hook A and a long load rejection hook B; tail ends of the long load rejection hook A and the long load rejection hook B of each set are respectively hinged on an unhooking bracket of the deep-sea structure frame, and ballasts are respectively hung; head ends of the long load rejection hook A and the long load rejection hook B are overlapped with each other; the long load rejection hooks B in the twosets of load rejection actuating mechanisms are respectively connected with connecting cables; the connecting cables on the two long load rejection hooks B are respectively connected with one end ofa common connecting cable; and the other end of the common connecting cable passes through the automatic unhooking device and is hung on the acoustic release transponder. According to the system disclosed by the invention, two load rejection schemes of the acoustic release transponder and the automatic unhooking device are adopted, and delayed load rejection can be performed by adopting the automatic unhooking device when the acoustic load rejection means fails.
Owner:SHENYANG INST OF AUTOMATION - CHINESE ACAD OF SCI

Low-power underwater load rejection device

The invention discloses a low-power underwater load rejection device which comprises a motor, a watertight barrel, a permanent magnet, an iron load rejection block, a connecting flange, a load rejection mechanism cover plate, a watertight joint fixing piece and a pressure-resistant wet-plug connector male head; the load rejection mechanism cover plate is fixedly sealedly connected with the watertight barrel; the motor is mounted in the watertight barrel; the upper end of the motor is electrically connected with a binding post of the end part of the pressure-resistant wet-plug connector male head; the connecting flange is fixed on the rotating shaft of the motor; the permanent magnet is fixed at the lower side of the connecting flange; a position, relative to the permanent magnet, of the bottom end of the watertight barrel is provided with a circular slot; a small part of the iron load rejection block is embedded into the circular slot and is inserted into or divorced from the slot according to the conditions; the circular slot plays a guiding role, to prevent the iron load rejection block from deviating the circular slot under the suction action of the permanent magnet when the permanent magnet is displaced under the action of the motor. The device can smoothly discard ballast, has low power consumption and easy and quick ballast installation process, and ensures that an underwater aircraft can form positive buoyancy and can be normally recovered to the water surface.
Owner:SHANGHAI JIAO TONG UNIV

Working condition control device in pump turbine speed adjusting system and control method of working condition control device

The invention discloses a working condition control device in a pump turbine speed adjusting system and a control method of the working condition control device. The device comprises a main distributing valve, a shuttle valve cartridge valve set, a cartridge valve, a working condition selecting valve, a servomotor, a sequence closing valve set, a guide vane control ring, a check valve, an electro-hydraulic control oil input port, a pressure oil input port, three throttling oil discharging ports, a control oil input port and a throttle valve. Selection of working conditions is conducted through the working condition selecting valve, and then when load shedding is conducted under the situation that a pump turbine unit breaks down, sequence closing of guide vanes under the working condition is achieved through cooperation of the main distributing valve, the shuttle valve cartridge valve set, the cartridge valve and the like. According to the working condition control device and the control method, the working condition selecting valve and the shuttle valve cartridge valve set are additionally arranged in the device creatively, different closing rules of the same device under different working conditions are achieved, rising of the load shedding pressure of the unit under multiple working conditions is reduced, and the running section and range of the unit are enlarged; and protection on the unit is reliably improved, and the beneficial effects that the structure is simple, cost is low and control is accurate are achieved.
Owner:QINGYUAN PUMPED STORAGE POWER GENERATION CO LTD +1
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