30 results about "Stress axis" patented technology

The invention discloses a build-up force standard machine with a wide range, belongs to the technical field of force standard machinery, and is characterized in that the build-up force standard machine comprises a first detecting unit and a second detecting unit, wherein the upper limit of the range of the first detecting unit is in accordance with that of the build-up force standard machine; the lower limit of the range of the first detecting unit is in accordance with the upper limit of the range of the second detecting unit; the lower limit of the second detecting unit is in accordance with that of the build-up force standard machine; the force output directions of the first and the second detecting units are in accordance with each other; and the stress axis of a to-be-detected sensor is overlapped with those of the first and the second detection units. The build-up force standard machine has the advantages of large range, low manufacturing cost and the like.

The invention provides a method for determining a polycrystalline metal deformation activation slippage system and belongs to the field of analysis of a material mechanical property. The method comprises the following steps: carrying out crystal orientation analysis on the surface of a test sample by adopting an EBSD analyzer; analyzing a loaded slippage band appearance by adopting a laser co-focusing microscope; calculating an included angle between a slippage band and a loading stress axis and comparing with an actual measurement value to determine a slippage surface; calculating a Schmid factor of a possible slippage system corresponding to the slippage surface; and determining a slippage direction according to a Schmid principle. Existing analysis methods mainly comprise five methods including an accrual method, a diagrammatizing method, a tensile axis index observation method, an X-ray diffraction method and a transmission electron microscope method. The first three methods are used for speculating a theoretical slippage system, and cannot be used for determining an actual activation slippage system; and the last two methods cannot be used for analyzing crystal orientation and damage appearance at the same time. The method can be used for analyzing the orientation of grain crystals and the corresponding slippage band appearance, and is relatively suitable for activation slippage system analysis after polycrystalline metal mechanical deformation.

This invention relates to stress balance relation lock, which comprises the following parts: lock case, case cover, main control drive structure, stress executive structure, semi-axis, locking stress axis, reset sensor device. The invention is characterized by the following: the stress executive structure an lock stress axis form mechanic stress relationship through main control drive structure main gear and passive gear; the bearing dial bolt lifts or contracts through stress axis, lock bolt; the passive stress gear axis line and lock stress axis vertical middle line are overlapped to generate lock dead angle at 15 degrees.

The invention discloses a multi-iron-heterogeneous magnetic field sensor adjustable in measuring range and a measuring range adjusting method. The magnetic field sensor comprises a bottom metal electrode layer, a free layer, an isolation layer, a pinning layer and a top metal electrode layer which are arranged from bottom to top in sequence. The free layer is of a multi-iron-heterogeneous multi-layer structure and comprises a ferroelectric layer and a first ferromagnetic layer from bottom to top in sequence. The pinning layer is of a multi-layer structure and comprises a second ferromagnetic layer and a reverse ferromagnetic layer from bottom to top in sequence. A ferroelectric stress axis direction of the free layer is perpendicular to a magnetic moment direction of the pinning layer in horizontal projection. The measuring range adjusting method comprise the steps that: a measuring range switching voltage V is applied to the ferroelectric layer of the magnetic field sensor, the ferroelectric layer is enabled to generated an electric field stress, the first ferromagnetic layer is under the effect of the electric field stress, and a saturated magnetic field is changed, so that the measuring range of the magnetic field sensor is changed. The invention provides the multi-iron-heterogeneous magnetic field sensor simple in structure, small in size and convenient and flexible, and the measurement precision of the sensor in a low magnetic field is ensured.

The invention discloses a fatigue testing method for a rail transportation vehicle body welding structure, and belongs to the technical field of fatigue testing. The method comprises the following steps: 1, making preparations before testing: performing numerical simulation analysis to determine a load value; 2, assembling a test sample and a fixture: rigidly clamping and fixing a straight vehicle body section of the vehicle body welding structure test sample by adopting a rigid clamping end and elastically clamping and fixing an irregularly-shaped vehicle body section by adopting an elastic clamping end, to form a combined test body; 3, fixing the combined test body on a fatigue tester; 4, performing loading test according to the load value; 5, performing detection. According to the method, any shape can be effectively fixed and clamped by rigid and flexible combination, and the actual stress centerline of the welding structure is overlapped with the loading stress axis of the fatigue tester, so that the fatigue level of the rail transportation vehicle body welding structure can be accurately measured.

The invention belongs to the technical field of asphalt mixture shear behavior testing, and relates to a testing device of the pressure-torsion shear failure performance of an asphalt mixture. The device provides a constant-temperature environment through an outer circulating heat preservation system and exerts axial pressure and torsion loads on asphalt mixture test pieces in an independent or combination mode. A dual-layer plane ball bearing is arranged, transmits axial pressure to a left fixed plate and releases torsion loads; a square-section section is arranged at the right end of an axial pressure loading shaft, and torsion loads are borne by a square hole of a right fixed plate; a spring is arranged to buffer axial pressure loads. A torque sensor and a pressure sensor which are completely separated spatially are adopted, the measuring ranges of the two sensors do not need to be matched, and the two sensors do not influence each other. By means of the device, the failure process of the asphalt mixture in the moderate and high temperature environment and the complicated torsion stress state can be simulated; when the torsion loads continuously change, the direction of the main stress axis of a test piece continuously changes, and the change characteristic of the real stress state of a road surface is met.

The invention provides a fixed-axis fiber distributing device of polarization-maintaining optical fiber and a method thereof. The fixed-axis fiber distributing device of the polarization-maintaining optical fiber comprises a stress axis angle detection mechanism, a stress axis control mechanism, an automatic glue dispensing mechanism, a fiber moving mechanism, an image processing unit and a control unit, wherein the stress axis angle detection mechanism is used for detecting light intensity information of light transmitting through a base belt and the polarization-maintaining optical fiber inreal time; the image processing unit is used for calculating an azimuth angle of an optical fiber stress axis according to the light intensity information; the control unit is used for judging whetherthe azimuth angle of the optical fiber stress axis meets the requirement or not, rotating the angle of optical fiber through the stress axis control mechanism if the azimuth angle of the optical fiber stress axis does not meet the requirement; carrying out a glue dispensing operation through the automatic glue dispensing mechanism if the azimuth angle of the optical fiber stress axis meets the requirement, and subsequently driving the base belt and the optical fiber to move through the fiber moving mechanism. Through the fixed-axis fiber distributing device of polarization-maintaining opticalfiber and the method thereof, the polarization-maintaining optical fiber can be paved on the base belt according to the set angle to form a pressure sensor; the accuracy of a sensing unit of the pressure sensor can be ensured.

The invention relates to a multi-wavelength filter based on a polarization-maintaining fiber grating, which belongs to the fields of optical fiber communication and instrumentation. A chirped fiber grating (15) is written on a polarization-maintaining fiber (11), and a phase shift (16) is introduced into the chirped fiber grating. Under the action of the stress axis X (12) and the stress axis Y (13) of the polarization-maintaining fiber, the refractive index of the fiber core (14) on the X-axis and the Y-axis is different, forming birefringence, from the polarization-maintaining chirped fiber grating ( The spectrum of 15) has two mutually symmetrical polarization transmission peaks (21) and (22), and the bandwidth of each polarization transmission peak is consistent with the bandwidth of a chirped fiber grating on an ordinary optical fiber. When a phase shift (16) is introduced into the chirped fiber grating (15), corresponding extremely narrow narrow The position of the slit in the bandwidth range can be changed by changing the position of the phase shift introduced, and the transmission depth of the slit can be changed by changing the phase shift amount θ introduced by the phase shift, and the filter wavelength of the slit can also be finely adjusted at the same time, changing The number m of phase shifts can be introduced to change the filtering number of the filter.

The invention discloses a lead screw guiding device used on a testing machine. The lead screw guiding device comprises an upper cross beam and a lead screw; the lead screw comprises a lead screw thread part and a positioning shaft part; the lead screw guiding device is characterized in that a guiding positioning hole matched with the positioning shaft part is formed in the upper cross beam; the positioning shaft part is arranged in the guiding positioning hole; a bearing hole is formed in the inner upper end of the guiding positioning hole; a self-lubricating bearing is mounted in the bearing hole; a bearing end cover is arranged at the upper end of the self-lubricating bearing; the bearing end cover is fixedly connected with the upper cross beam through bolts. The lead screw guiding device is simple in structure; the arrangement of the self-lubricating bearing ensures the accuracy in positioning and guiding of the lead screw, so that the coaxiality requirement of a stress axis and a host axis during the testing process of a sample can be met, and simultaneously, the friction received by the upper cross beam during the up and down movement process can be reduced.

The invention provides a pulling force metering device for a micro-force value measuring instrument. The device comprises an equal arm balance, and the equal arm balance comprises a balance cross beam, a left pallet and a right pallet. The right side of the balance cross beam is provided with a light support, and the lower part of the light support is provided with a small hole through drilling. The central axis of the small hole is required to be consistent with a stress axis of a right edge of the equal arm balance. A working platform is fixed above the right pallet, and is provided with a three-dimensional workbench. The micro-force value measuring instrument is fixed on the three-dimensional workbench, and a force bearing point of the micro-force value measuring instrument is connected with a balance hook for hooking the right pallet through a fine rope. The device can guarantee that the pulling force metering of the micro-force value measuring instrument with the range from 2mN to 10N meets force value metering requirements, and solves a key technical difficulty in building a (pulling) metering standard device for the verification/correction of the micro-force value measuring instrument.

The invention relates to a stock bin weighing device. The upper end and the lower end of a column type weighing sensor are provided with a bearing head and a connecting head respectively, external threads are formed on the bearing head and the connecting head, the bearing head is in threaded connection with an upper flange plate, a bearing table is connected at the upper end of the upper flange plate, the upper end of the bearing table is provided with a retractable locating step, the connecting head is in threaded connection with a lower flange plate, a supporting seat is connected with the lower end of the lower flange plate, the bottom surface of the supporting seat is oblique relative to the horizontal plane, and a tubular landing leg at the bottom of the stock bin is arranged on the locating step of the bearing table in a sleeved mode for welding on site conveniently, therefore, the aesthetic degree and the connecting strength are improved; the bottom surface of the supporting seat is seated on the ground of the installation site, the stressed axis of the column type weighing sensor in the weighing device is coincided with the stressed direction of the landing leg, so that the influence of lateral force caused by inconsistence of the stressed direction of the tubular landing leg and the weighing sensor is eliminated; and the column type weighing sensor and the upper flange plate or the lower flange plate rotate oppositely, therefore, a distance between the upper flange plate and the lower flange plate can be accurately and conveniently adjusted.

A method for making a semi-conductor nanocrystals, including at least the steps of:

• • making a stack of at least one uniaxially stressed semi-conductor thin layer and a dielectric layer,
  • annealing the semi-conductor thin layer such that a dewetting of the semi-conductor forms, on the dielectric layer, elongated shaped semi-conductor nanocrystals oriented perpendicularly to the stress axis.

A device for managing an accumulator, including: a plurality of strain gauges including at least three strain gauges, the strain gauges being arranged to measure stresses along at least three distinct stress axes; a measuring device measuring strains undergone by each gauge along its stress axis; a reversible electrical switch; a calculating device controlling opening and closing of the electrical switch, depending on measurements carried out by the measuring device.

The elastic brace (7) has first and second connecting parts (9, 11), which are formed at both ends, and an elastic part (13), which is located between the first and second connecting parts (9, 11) . The elastic portion comprises a plurality of planar segments (15) in the direction of the waves. The connection part is in the same plane as the stress axis. Each plane segment (15) has an included angle with each other and with the connection part, so each plane segment (15) is in the transverse direction of the stress axis.