624 results about "Leakage test" patented technology

A method of measuring the transistor leakage current. In one embodiment, the method involves driving a ring oscillator with a dynamic node driver having a leakage test device biased to an off state to produce a test signal. The test signal is extracted and the frequency is measured. The leakage current is estimated from the measured frequency.

A leak detection system capable of automatically detecting a leak in a pressurized piping system. A pressure decay test is utilized to test for leaks in the piping system. Disruption to users of the piping system is reduced by only performing the pressure decay test when there is no user demand on the piping system. Thus, a leakage test is performed by first determining whether there is user demand on the piping system and proceeding with a pressure decay test only if there is no user demand present. If user demand is initiated during the performance of a pressure decay test, the system detects the user demand and halts the pressure decay test until the user demand stops.

The invention relates to a test sorting machine for a battery product and a sorting method for the test sorting machine. The test sorting machine comprises a feeding device, a short circuit test sorting device, a station turntable, a leakage test device, a leakage test sorting device, a weighing device, a weighing taking device and a weighing sorting device, wherein the leakage test device is arranged on a table-board of one side of a leakage test station; the short circuit test sorting device is arranged on a working table-board of one side of a short circuit test qualified product placement station; the feeding device and a short circuit placement region are arranged in front of the short circuit test sorting device; the leakage test sorting device is arranged on one side of a leakage test taking station; a leakage test unqualified product placement region and a leakage test qualified product conveying chute are formed on a working table-board of the front side of the leakage test sorting device; the weighing device is arranged at the outlet end of the leakage test qualified product conveying chute; the weighing taking device is arranged on the front side or the rear side of the weighing device; and the weighing sorting device is arranged on one side between the weighing device and a conveying device. The test sorting machine can perform multi-detection and sort batteries of different standards at the same time, so the working efficiency is high.

A test structure and method for determining DRAM cell leakage. The cell leakage test structure includes a pair of buried strap test structures. Each buried strap test structure includes multiple trench capacitors formed in a silicon body. Each trench capacitor is connected to a trench sidewall diffusion by at least one buried strap. An n-well ring surrounds each buried strap test structure and divides the buried strap test structure into two separate array p-wells, one being a contact area and the other a leakage test area. The contact area includes contacts to the trench capacitor plates for the corresponding buried strap test structure. In one buried strap test structure, a layer of polysilicon, essentially covers the trench capacitors in the leakage test area to block source/drain region formation there. The other of the two buried strap test structures includes polysilicon lines simulating wordlines with source and drain regions form on either side. A buried n-band contacts the n-well rings, essentially forming an isolation tub around each array well. Cell leakage is measured by measuring leakage current in each buried strap test structure, individually, and then extracting individual leakage components from the measured result.

The invention relates to a method for brazing a compact efficient titanium alloy plate-fin heat exchanger, which adopts an amorphous titanium based brazing filler metal brazing titanium alloy with lower melting point which is between 820 and 840 DEG C, wherein the optimum clearance of the amorphous titanium based brazing filler metal brazing titanium alloy is between 20 and 90 microns, the optimum brazing temperature is between 850 and 900 DEG C, the optimum brazing time is between 10 and 15 minutes, the heating rate before soaking a workpiece is between 10 and 15 DEG C per minute, the heating rate for brazing after the soaking is 15 DEG C per minute, the cooling rate for the brazing filler metal to become solid from liquid is not less than 15 DEG C per minute, and a vacuum system only can be closed when the temperature is below 150 DEG C. Through strict selection and purchase of materials, precise part machining, careful part cleaning, brazing filler metal arrangement according to a process, precise assembling and clamping, and performing brazing according to a stated brazing process, a helium gas leakage test shows that the integral leakage of the product is 9*10<-8>PaM<3>/S which is in accordance with the standard requirement.

A fail-safe circuit for a pair of differential input lines detects when one or both lines are open. Each line has a pull-up of a switched p-channel transistor in series with a resistor or another p-channel transistor that has its effective resistance controlled by a gate bias. The gate of the switched p-channel transistor is driven to ground when power is applied to the gate of a grounding n-channel transistor. When power is off, a p-channel connecting transistor charges the gate node from the differential input line when a positive voltage is applied to the input line, such as during a leakage test. Charging the gate node prevents the switched p-channel transistor from turning on, blocking a leakage current path through the pull-up. An N-well bias circuit can be added, which connects the N-well under p-channel transistors to power or the gate node or the input line.

This invention provides a leakage test method and a device including: marking a basic tendency of an underground line to be tested, injecting a tracer gas in a certain pressure composition of 5% hydrogen and 95% nitrogen to the line, testing the H2 signal along the tendency of the pipeline with a H2-sensitive probe of a movable hydrogen leak detector, converting the test signal to an electric signal then converting it to a digital signal by A/D conversion, memorizing and analyzing the continuously tested digital signals to judge the leakage orientation based on the change trend weak or strong of the test signal and judging the accurate position of the leak point by comparing with the maximum value of the memory and an indicator displays the maximum value of the concentration of the tested hydrogen and indicates the location of the direction and leakage definitely. Advantage: direct indication, accurate location to reduce work intensity of test.

The invention discloses a leakage circuit breaker which has a simple and small structure of a test circuit and can simultaneously perform accurate leakage tests. As a power supply circuit for supplying power to the leakage detection circuit in the leakage circuit breaker, a power supply circuit with a constant current circuit that converts the AC current supplied from the main circuit into a DC current and supplies a constant DC current to the leakage detection circuit is used, and the test resistance The elements are arranged in series in the circuit connecting the main circuit and the AC input end of the current stabilizing circuit, and the test coil of the zero-phase converter is connected to both ends of the resistance element through a test switch to form a leakage test circuit.

A receptacle device for protection against arc faults and leakage currents, including an arc fault test button, a leakage test button, and a reset button. Test resistors are arranged below the arc fault test button and the leakage test button wherein the test resistors are coupled to an electrical circuit board. The electrical circuit board includes an arc sampling resistor to detect arc faults and a leakage detection differential transformer to detect leakage currents. In order to provide good contacts between mobile and stationary electrical contacts of the receptacle device, a reset button bias member having mobile contact bridges at its two arms is provided. Each of the mobile contact bridges has three triangularly spaced electrical contacts, corresponding to stationary electrical contacts of flexible input fingers, output conductors and electrical output leads of the receptacle device. In order to balance the mobile contact bridges and provide better contacts, the receptacle device of the present invention can utilize a unique system of dual directional locks, i.e., below the reset button, there are two axially symmetrical directional locks provided within a reset button bias member of the receptacle device.

The invention relates to a pipeline leakage test set and method. The test set comprises a power system, a leakage unit, a valve, a temperature meter, a volume flowmeter and a pressure meter. The power system is connected with the leakage unit through a pipeline. Two ends of the leakage unit are respectively connected with the valve, the temperature meter, the pressure meter and the volume flowmeter. Calculated and metered values of gas or liquid stable leakage rates are compared to obtain a correcting model of a gas or liquid stable leakage rate equation; the model is applicable to the research on features and regulations of stable and dynamic leakage of gas, liquid or gas-liquid mixture in pipes or storage tanks under various different leakage conditions; the theoretical basis for the daily safety maintenance of long-distance pipelines and the emergency relief and investigation of leakage accidents is provided.

A method for monitoring an evaporative emissions control (EVAP) system that includes compensating a diagnostic leakage test based on a fuel consumption amount during a test interval is disclosed. The method includes establishing a leak test pressure in the EVAP system, operating the operating the associated valves and pumps such that the EVAP system is expected to be isolated, determining an actual pressure change of the EVAP system, determining an expected pressure change of the EVAP system based on vehicle operating conditions that include the fuel consumption amount, and indicating that a leak is detected if the actual pressure change differs from the expected pressure change by more than a difference threshold.

A plating method includes holding a substrate with a substrate holder while bringing a sealing member into pressure contact with a peripheral portion of the substrate to form an enclosed internal space in the substrate holder; performing a first-stage leakage test of the substrate holder by producing a vacuum in the internal space and checking whether pressure in the internal space reaches a predetermined vacuum pressure within a certain period of time; and if the substrate holder has passed the first-stage leakage test, performing a second-stage leakage test of the substrate holder by closing off the internal space after producing the vacuum therein and checking whether a change in the pressure in the internal space reaches a predetermined value within a certain period of time.

The invention relates to a portable multifunctional insulated instrument test rack belonging to a working experiment table for carrying out pressurization and current leakage tests on an insulated instrument and a lightning arrester. Four insulated columns are fixed on a rectangular aluminum alloy platform, an insulated connecting rod is arranged between the upper parts of the two adjacent insulated columns to form an insulated frame part which is provided in parallel with more than two aluminum alloy rods, a test pressurization line is fixed on one of the aluminum alloy rods, insulating rods are fixed on the rest aluminum alloy rods, a clamp is fixed at the lower end of each insulating rod, an aluminum alloy water tank with a cover is arranged on the rectangular aluminum alloy platform, a hole is arranged in the cover of the water tank, the lower end of the test pressurization line penetrates into the water tank from the hole in the cover, and a grounding bolt is arranged on a water tank panel. The invention has the advantages of convenient use and experimental time saving and is suitable for the tests of insulated instruments and lightning arresters of different specifications under 35 Kv.

The invention relates to a novel leakage detecting-positioning method of urban natural gas pipelines and a system thereof. An infrared laser device, a laser device temperature and current controller and a signal generator are arranged in a case. A light outlet of the infrared laser device is positioned at the front end of a light inlet window sheet of a multiple-reflection absorbing pool, wherein, an air outlet of the multiple-reflection absorbing pool is connected with a micro suction pump, and an air inlet thereof is connected with a hose. The end of the hose is connected with a sampling probe. An exhaust port of the micro suction pump is communicated with the atmosphere out of the case. The laser entering the multiple-reflection absorbing pool is radiated out from the light outlet window sheet of the multiple-reflection absorbing pool and received by a laser detector. A signal output of the laser detector conducts a signal treatment. The sampling probe adopts air suction type sampling so as to lead the detection to be more flexible and convenient as well as provide high resolution. By adopting a laser spectrum technology which reacts to CH4 only, the detection limit reaches one part per million (PPM) level and the fine change of the density of the CH4 gas around a leakage point caused by the leakage of the natural gas pipeline can be detected.

The invention belongs to the field of petroleum engineering, and particularly relates to an experimental device and an experimental method for simulating dynamic leakage and leaking stoppage of drilling fluid. The experimental device for simulating the dynamic leakage and leaking stoppage of the drilling fluid comprises a first high-pressure nitrogen bottle, a first circulating cylinder, a leakage test cylinder, a second circulating cylinder, a second high-pressure nitrogen bottle and a servo control injection pump, wherein the first high-pressure nitrogen bottle is connected with the bottom end of the first circulating cylinder; the two ends of a fifth high-pressure pipeline are respectively connected with the upper end of the first circulating cylinder and the upper end of a rock core clamping device; the servo control injection pump is connected with the lower end of the leakage test cylinder; the second high-pressure nitrogen bottle is connected with the bottom end of the second circulating cylinder; the two ends of a fourth high-pressure pipeline are respectively connected with the upper end of the second circulating cylinder and the upper end of the rock core clamping device. According to the experimental device and the experimental method, the positive circulating and positive circulating dynamic leaking stoppage processes of the drilling fluid on the end surfaces of rock cores with different lithological characters in an original crustal stress state can be really simulated; the simulated rock core size is large; the experimental method is simple; the experimental error is small; the experimental device and the experimental method have higher guidance value to field application.

An airtight tester is used to test air tightness at a testing position of an object to be tested. The airtight tester includes a base, a leakage-test pipe, a moving unit, and a detector. The leakage-test pipe is connected to a pressure source, such that the pressure source may output a pressure to the leakage-test pipe. When the leakage-test pipe covers at the testing position of the object, the moving unit is pressed at an outer edge of the leakage-test pipe, so that the leakage-test pipe is jointed to a surface of the object, and thus, the detector detects the pressure state of the leakage-test pipe. Therefore, the testing staff obtains the air tightness of the object through an output message of the detector, and thus strengthening the structure of the object through utilizing the information.

The invention discloses an all-hydraulic steering gear test system, which comprises an oil tank, a motor pump system, a pressure and flow control valve system, a temperature control heating system, a filtering system, a circulation cooling system, an oil circuit switching control system, a steering power loading module, a bridge-type analog loading module, an oil cylinder working condition loading module, a sensor data acquisition module, an electronic control system and a computer data processing center. According to the all-hydraulic steering gear test system, the switching control of various oil circuits can be carried out by the oil circuit switching control module, the test of a load sensing type steering gear and other steering gears of the same type can be realized, the types of test items are more complete and comprise a power steering performance test, an end point sensing end point slippage test, a neutral position replaying test, a pressure loss test, an internal leakage test, a flow change rate test, a manual steering voltage efficiency test, a road sense test and the like, and the test requirements on the all-hydraulic steering gear in China and abroad can be met.

A circuit breaker for overcurrent protection and earth leakage protection includes a main housing, a circuit board, a zero-phase current transformer, an earth leakage detection circuit, a trip coil, a sensitivity current-switch, an action time switch, and an earth leakage test switch. The earth leakage detection circuit, the sensitivity current-switch, the action time switch, and the earth leakage test switch are mounted on the circuit board and installed in the main housing.