244 results about "Dynamic resistance" patented technology

The present invention relates to compositions which contain at least one epoxide adduct A having on average more than one epoxide group per molecule, at least one polymer B of the formula (I), at least one thixotropic agent C, based on a urea derivative in a nondiffusing carrier material, and at least one curing agent D for epoxy resins, which is activated by elevated temperature. This composition serves in particular as an adhesive and has an extremely high dynamic resistance to cleavage, in particular at low temperatures. The invention furthermore relates to impact strength modifiers terminated with epoxide groups and of the formula (I). It has been found that these novel impact strength modifiers result in a significant increase in impact strength in epoxy resin compositions, in particular in two-component epoxy resin compositions.

An exercise machine which allows a user to perform a variety of exercises using dynamic resistance. The exercise machine includes a platform base, a housing tower, an upper-left exercise module, an upper-right exercise module, and a control console. The upper-left exercise module and the upper-right exercise module each comprise a primary torque motor, a primary cable, a pulley system, a structural arm, and a primary handle. The housing tower is connected onto the platform base. The upper-left exercise module and the upper-right exercise module are integrated into the housing tower and provide a means for applying a resistance force onto the extremities of the user. The primary cable tensionably engages the pulley system and connects the primary handle to the primary torque motor. The primary handle rests within and against the structural arm, attached to the housing tower. The control console allows for external device compatibility.

The invention discloses a device for measuring dynamic resistance of a high-voltage circuit breaker. The device is characterized by at least comprising a super capacitor module (5), a super capacitor charging device (10), a current sampler (4) and a voltage sampler (2), wherein the super capacitor module (5) supplies measuring power supplies with different requirements for measuring switch-on resistance (11) and loop resistance (14) of the high-voltage circuit breaker (3); a charging controller (7) and an electronic switch (16) are controlled by a digital processor (1) so as to control charging and discharging of a super capacitor; and an electric signal is acquired and processed quickly by the digital processor (1) so as to quickly obtain a measuring result on site. Measurement of switch-on resistance, loop resistance and switch-on resistance making time of the high-voltage circuit breaker is integrated and the measuring results of three parameters can be obtained through one-step measuring operation.

The present invention is directed to an LED light fixture. The LED light fixture comprises an interface for connecting the fixture to a source of electrical power, a power control section for supplying and controlling power to an LED array producing a light of a suitable intensity and color for the task for which the fixture is to be used and a light diffuser for diffusing the light from the LED array. The present invention is also directed to a novel power control for supplying and controlling power to an LED array comprising a non switching linear design based on a monolithic approach of power control whereby the load (the LED array) becomes part of the power control system.

The invention discloses an indoor power drainage consolidation testing system and method, relating to an indoor rock mechanics testing system and method. The system is composed of shock load applying device, straining three-axis pressure room, stress and strain senor, dynamic resistance strain meter, floating engineering dynamic meter, PC, and pressure frame; and the method includes the steps: (1) according to the diameter size of a sample, drilling a bore along the axis of the sample in proportion, and filling fine sand into it; (2) placing the drilled sample in the pressure room for reversal pressure saturation; (3) installing the shock load applying device on a force transferring pole, and installing the stress and strain sensor for testing aperture water pressure, shock stress and axial strain; (4) using data collector to make dynamic signal collection, transmission and recording.

The invention discloses a multifunctional electrical characteristic testing device and a multifunctional electrical characteristic testing method for a high-voltage circuit breaker. The testing device consists of a dynamic resistance detection module, a non-synchronism detection module, a displacement sensor, Hall current sensors, a data acquisition card, an industrial control computer and an industrial display screen, wherein a super capacitor is used as a power supply for the detection of loop resistance, and impact current with a peak value of 1,000A is used as detection current. The testing device is a multifunctional testing instrument integrating the detection of loop resistance, closing resistance, closing resistance running time and mechanical characteristics of the high-voltage circuit breaker.

The real-time dot welding molten kernel detecting method includes the following steps: performing several point welding with welded sample in the same thickness as the welded part, and measurement and calculation to obtain the dynamic resistance curve of each point; further obtaining the quasi-stable state resistances rD of each point; splitting the welded sample along the joint surface, measuring the molten kernel diameter dK of each welded point, and drawing the rD vs dK curve; storing rD vs dK curves of different material thickness in computer system; and comparing the practical molten kernel diameter with the set standard value to judge welding quality.

The invention discloses a piezoelectric plate vibration detection and control device and method based on a laser displacement sensor. The device comprises a flexible plate, a mechanical support clamping device, the laser displacement sensor, an ARM development plate, a piezoelectric amplifying circuit, a bending mode piezoelectric driver, a torsional mode piezoelectric driver, resistance strain gauge sensors, a dynamic resistance strain gauge, an A/D conversion circuit, a D/A conversion circuit, a computer and the like; the flexible plate is fixed through one end of the mechanical support clamping device, the multiple piezoelectric ceramic plate drivers and the resistance strain gauge sensors are sticked on the flexible plate, and the laser displacement sensor is installed right opposite to the flexible plate. Decoupling of bending and torsional vibration detection is achieved through the vibration detection advantage of the laser displacement sensor, the measurement value of resistance strain gauges can be dynamically calibrated, and by combination with an operating active control algorithm, controlling quantity is exerted on the piezoelectric ceramic plate drivers through the piezoelectric amplifying circuit, and the purpose of actively controlling the bending and torsional vibration of a piezoelectric plate is achieved.

According to an embodiment, a transient voltage protection circuit includes a first integrated circuit including an input node, an output node, a first transient voltage protection component coupled between the input node and a reference voltage node, and an impedance element coupled between the input node and the output node. The first transient voltage protection component has a first dynamic resistance and the output node is configured to be coupled to an electrostatic discharge (ESD) protection component having a second dynamic resistance that is greater than the first dynamic resistance.

A field emitter array structure is provided. The field emitter array structure includes a plurality of vertical un-gated transistor structures formed on a semiconductor substrate. The semiconductor substrate includes a plurality of vertical pillar structures to define said un-gated transistor structures. A plurality of emitter structures are formed on said vertical un-gated transistor structures. Each of said emitter structures is positioned in a ballasting fashion on one of said vertical un-gated transistor structures so as to allow said vertical ungated transistor structure to effectively provide high dynamic resistance with large saturation currents.

The invention provides a method for detecting the quality of a conductive sliding ring, relating to a method for detecting the conductive sliding ring, and solving the problem that the conventional method for detecting the conductive sliding ring cannot represent the change of the total dynamic resistance of the conductive sliding ring and the contact resistance between an electric brush and a sliding way. The method comprises the following specific steps of: placing a conductive sliding ring to be detected on a conductive sliding ring test tool to enable the conductive sliding ring to be operated at a constant rotation speed omega; and measuring a dynamic resistance y(t); according to the total resistance of the conductive ring, obtaining a total resistance R of a circle of the conductive ring to be detected, and calculating to obtain a resistance equivalent direct-current component R0 of the conductive sliding ring by comparing the ideal dynamic resistance with the actually measured dynamic resistance y(t) and the parameter R; solving to obtain a residual effective value rho of the conductive sliding ring to be detected according to the parameters R and R0, wherein the rho represents the quality of a process for manufacturing the electric brush of the conductive sliding ring and the conductive sliding ring; and calculating to obtain a mean value and a maximum fluctuation delta Rmax according to the y(t), and obtaining a fluctuation peak value Rpp according to the parameter R, wherein the material used by the conductive ring and the conductivity are reflected by the mean value, the maximum fluctuation delta Rmax and the fluctuation peak value Rpp. The method for detecting the quality of the conductive sliding ring provided by the invention is applicable to the quality detection of the conductive sliding ring.

A testing system for testing vibration fatigue performance of an aircraft fuel tank is composed of an electromagnetic vibrator, a sample clamp, a signal output unit, a stabilized voltage supply, a frequency meter, a resistance strain gage, a dynamic resistance strain gauge, a sample and a clump weight. The clump weight is installed in the middle of the sample. The sample is mounted on the sample clamp, and pretension force can be applied by screwing studs on the sample clamp. The sample clamp is installed on the electromagnetic vibrator. The stabilized voltage supply is connected with the signal output unit. The signal output unit is connected with the electromagnetic vibrator so as to control the electromagnetic vibrator. The stabilized voltage supply is simultaneously connected with the frequency meter so as to monitor output excitation frequency. The resistance strain gage adhered to the sample is connected with a dynamic strain meter so as to monitor strain of the sample. The dynamic resistance strain gauge is connected with the frequency meter so as to monitor response frequency of the sample. The testing system has a simple structure, is convenient to operate and is used for testing vibration fatigue performance of an aircraft fuel tank. A test result has important engineering application value for evaluation of structure fatigue life.

The invention discloses a test method for welding spot quality of resistance spot welding based on dynamic resistance curve. The method comprises the following steps: calculating dynamic resistance changing curve and average dynamic resistance according to a welding current signal, an electrode voltage signal and welding current duration detected during the welding process of resistance spot welding in real time, further drawing a relation curve based on the calculated average dynamic resistance and the welding spot diameter and welding spot maximum bearing capacity obtained by destructive detection on corresponding welding spot, and thereby building an average dynamic resistance-welding spot diameter mathematical model and an average dynamic resistance-welding spot maximum bearing capacity mathematical model; in actual welding process, comparing the detected dynamic resistance curve with a standard dynamic resistance curve to judge nucleation situation of the welding spot; and calling corresponding mathematical model from a database, inputting the detected average dynamic resistance, calculating and outputting a diameter value and a maximum bearing capacity value of the welding spot by a computer, if the output values are less than corresponding given thresholds, judging that the welding spot is unqualified. By the test method provided by the invention, non-destructive detection and evaluation on diameter and maximum bearing capacity of the welding spot of resistance spot welding can be realized quickly, and the test method is particularly suitable for on-line quality detection in the welding production field.

The invention discloses a three-dimensional simulating method for goaf fracture ring morphology. The method comprises the steps that according to the space similarity ratio between a coal seam and overlaying rock and time similarity ratio of coal seam working face propelling, a three-dimensional similar simulation test body is manufactured; according to the site mining working face ground stress situation and the mining sequence, the dynamic process of coal mine working face propelling under the three-dimensional stress condition is simulated; an embedded stress sensor is utilized for monitoring stress changes of a top plate and a bottom plate of a goaf in the mining working face propelling process, and a dynamic resistance strain gauge is utilized for recording data; after mining working face propelling simulation is finished, a tracer agent labeling method is used for carrying out drilling to pry and observe the goaf fracture morphology of the simulation test body, the top plate and the bottom plate of the goaf are separated layer by layer and section by section, and statistics is carried out on fracture data of all layers and all sections; according to the statistical fracture data, three-dimensional software is utilized for drawing a goaf fracture ring morphology simulation image. The method has the advantages that a three-dimensional mode is adopted for simulating the goaf fracture development morphology, and therefore the position of extraction holes can be determined conveniently and accurately.

A low-dropout regulator with a single-transistor-control providing improved transient response and stability is disclosed. The single-transistor-control provides a dynamic resistance at the output of the regulator for minimizing undershoot and overshoot, and hence improves transient response. Since the single-control transistor reduces the output resistance of the regulator, the output pole is pushed to a sufficiently high frequency without affecting stability. Therefore, the limited choice of combinations of the output capacitance and its equivalent-series-resistance is substantially relaxed.

The invention relates to a non-splashing dynamically heating self-adaptive resistance welding method for automobile metal sheets, which comprises the following implementation steps: firstly, a nugget formation process is enabled to be kept in the state of non-splashing power-on heating fusion and cooling crystallization heat balance in the way that a non-secondary rectification welding transformer and a pulse width adjustable alternate current contravariant power supply are utilized and different metallic materials thermal balance factors are called; the nugget size is controlled through detecting the change rate of dynamic resistances at the two ends of electrodes. According to the invention, as a non-splashing thermal balance factor, namely t+t0, is adopted in the method, the splashing problem in the welding is effectively solved, and the welding quality is improved; the change rate of dynamic resistances at the two ends of the welding electrodes during the welding can be detected to quickly judge the nugget formation process, so that the interference in the measuring is reduced, and the reliability of the detection is improved; besides, the difficult problem that a plenty of splashes are generated in the welding of automobile metal sheets for a long time is effectively solved, the welding quality and the production efficiency are greatly improved, and the production and processing cost is greatly reduced.

The invention discloses a high voltage circuit breaker arc contact fault diagnosis method which includes the following steps: initializing reference characteristic quantity; acquiring a dynamic resistance-stroke curve of a high voltage circuit breaker arc contact to be diagnosed and acquiring the area enclosed by the curve in the tripping process arc contact contacting stage as characteristic quantity to be diagnosed; comparing the characteristic quantity to be diagnosed with the preset reference characteristic quantity, diagnosing the state of the high voltage circuit breaker arc contact according to a comparison result and outputting a diagnosis result. Due to the fact that the area enclosed by the dynamic resistance-stroke curve in the tripping process arc contact contacting stage is utilized as the characteristic quantity to be diagnosed, the burning state and the contacting position of the arc contact correspond to each other, the burning degree of the circuit breaker arc contact can be diagnosed accurately and visually, and the method provides a basis for evaluation of the state of a circuit breaker arc extinguish chamber and making of circuit breaker overhauling decision. The method has the advantages of being high in diagnosis accuracy and high in detection speed, facilitating detection, not requiring disassembly of a high voltage circuit breaker to be diagnosed and saving manpower and material resources.

The invention provides a dynamic grounding mode of a neutral point of a power distribution network in a medium-resistance and low-resistance way, and a ground fault line selection method, for the problem existing in a low-resistance grounding mode of the neutral point of the power distribution network at present. The grounding resistance value of the neutral point of the power distribution network can be dynamically converted according to requirements, namely, when the power distribution network is in a normal operating state, the neutral point is grounded through a resistor and a serially-connected medium resistor for limiting each kind of overvoltage in the power distribution network; when a displacement voltage of the neutral point rises to a fault starting voltage, it is determined that the power distribution network suffers from single-phase grounding immediately; firstly, a grounding fault region is determined according to the displacement voltage value of the neutral point, and at the moment, the low-resistance grounding mode is performed; the neutral point is grounded through the serially-connected medium resistor, a single-phase grounding fault line is selected out by a zero sequence current amplitude-comparing method, and at the moment, a high-resistance grounding mode is performed; and the grounding of the neutral point is converted to low-resistance grounding, and a fault loop current is accelerated to satisfy the detection sensitivity of a zero sequence current transformer so as to select out and cut away the fault line.

The invention relates to a test device and a test method for measuring the dynamic resistance coefficient of a sealing element at different temperatures and belongs to the field of material mechanical property test. The device comprises a machine seat, a horizontal direction dragging device, a vertical direction motive power loading device, a measuring platform with rolling wheels, a platform guide rail, a high and low temperature test box, a first force sensor, a second force sensor and a microcomputer with data processing program. According to the method, a servo motor is controlled through the microcomputer, a loading head is driven to carry out horizontal and vertical loading on the sealing element on the platform loaded in a temperature box, and the force sensors are used for measuring the positive pressure in the vertical direction and the friction force in the horizontal direction. The test device and the test method can measure the dynamic resistance of the sealing element under different loading and temperature conditions, and have the characteristics that the measurement is convenient and fast, the data is precise, and the like.

The invention discloses a wind-power slip ring detection system capable of simulating a real working state, comprising a working table, brackets and a support; the support is provided with a rotation shaft driving a rotor to rotate and a driving motor driving a rotation shaft; the system also comprises a low resistance tester for testing multi-path dynamic resistance of the power-wind slip ring, an insulation resistance tester for testing insulation resistance of the power-wind slip ring, and a voltage resistance tester for testing the voltage resistance capability of the power-wind slip. The invention designs a working table capable of bearing the product weight, adopts the rotation shaft to rotate the rotor to perform 360-degree rotation, and is provided with the brackets in cooperation with the stator of the product. As a result, when the rotor is rotating, the stator maintains a relatively fixed state. The invention can simulates the real working state of the wind-power slip ring, realizes the automatic detection of the product dynamic resistance, product insulation resistance and product voltage resistance capability, and improves the product quality and detection efficiency.