32results about How to "Achieving Accuracy Requirements" patented technology

The invention relates to a cold forging technology for a gear shaft; the cold forging technology is characterized in that a new technology of the cold forging forming of the inside and outside and split flow forging, a volume split flow space is arranged between the gear shaft diameter and a concave die, the metal flow resistance is reduced and the unit extruding force carried by the die is lowered by split flow; high-strength die steel and split structure are adopted to produce a gear hole forming die; the concave die is produced by adopting three-layer sleeve prestressed structure so as to improve the compression resistance of the die; a punch is made from an alloy steel material and used for the cold forging and precision forming of a complex gear form blind hole, which improves the forming quality and production efficiency of the gear hole, and lowers the consumption of the raw materials markedly. The cold forging technology of the invention has the advantages of achieving the smooth forming of the gear form blind hole, improving the production efficiency greatly, and improving the quality of the gear hole and the qualification rate of the product markedly.

The invention discloses a frame synchronization method and system for burst OFDM data transmission. The method includes: a receiver receives air interface data, down-converts and filters it to baseband sampling data, wherein the frame synchronization header of the baseband sampling data includes chirp Chirp signal and constant modulus signal in time domain. The chirp signal includes an upper chirp signal and a lower chirp signal; the receiver performs a synchronous search on the chirp signal; and the receiver performs a synchronous search on the time domain constant modulus signal. The frame synchronization method and system for burst OFDM data transmission of the present invention can satisfy the synchronization of receivers with a signal-to-noise ratio lower than 0 dB or a wide signal-to-noise ratio working range without setting more synchronization header data and without increasing hardware costs Acquisition probability requirements as well as timing accuracy requirements.

The invention discloses a reflecting type inverse compensator which is used for calibrating an aspheric surface zero detection compensator and comprises an interferometer, a lens, a negative lens and a reflecting spherical mirror, wherein an aspheric surface zero detection compensator to be calibrated is arranged between the interferometer and the lens; the negative lens is arranged between the reflecting spherical mirror and the lens; the lens is used for calibrating a high-level spherical aberration, and the negative lens is used for generating a quantitative spherical aberration; after a light ray passes through the negative lens and lens twice, the sum of the spherical aberration generated by the negative lens and the lens and a theoretical spherical aberration of the aspheric surfacezero detection compensator have the same size but opposite symbols; a single-wavelength diverging spherical wave emitted by the interferometer passes through the aspheric surface zero detection compensator to form a diverging spherical wave; the diverging spherical wave with a spherical aberration passes through the lens and negative lens in turn to reach the reflecting spherical mirror; a beam is reflected by the reflecting spherical mirror, and passes through the negative lens and the lens for the second time, and passes through the aspheric surface zero detection compensator and reaches the interferometer; and the interferometer detects the system aberration of the aspheric surface zero detection compensator.

The present invention relates to a single-phase hybrid power flow calculation method based on node current injection. The single-three-phase hybrid model constructed in 1 for the power flow calculation of the distribution network adopts the node current injection method to calculate the power flow of the distribution network. The present invention simultaneously considers the effects of zero-sequence and negative-sequence components on the single-phase model, and ensures the accuracy of the calculation while taking into account the calculation speed.

The invention provides an optical distance doubled dynamic collimation interferometer. The optical distance doubled dynamic collimation interferometer comprises a beam splitter, a motion bearing is arranged at one side of the beam splitter, the beam splitter and the motion bearing are arranged in a manner of forming a 45-degree included angle, two ends of the motion bearing are respectively connected with a connecting rod, and two corner reflectors are respectively arranged on the connecting rods; a dynamic collimation reflector is arranged in a manner of forming the 45-degree included angle with the beam splitter, a transmission light of the dynamic collimation reflector is reflected to the corner reflector below, corresponding movable reflector is combined, and the corner reflector overthe movable reflector is used as a fixed reflector. The optical distance doubled dynamic collimation interferometer provided by the invention has the benefit that effective optical distance of the dynamic collimation interferometer is doubled without adding the scanning stroke of the movable reflector, and the resolution ratio of a FTIR is improved; structure of the interferometer is greatly simplified to be more compact, the volume and the weight of the interferometer can be greatly reduced, and implementation of miniaturization of the interferometer is facilitated; a dynamic collimation control system is used, the dynamic collimation reflector continuously adjust the posture according to the returned information, so that the interference can be always in the best status, and requirementon accuracy of guide rails is reduced. The optical distance doubled dynamic collimation interferometer implements the perfect match of the cost and the benefit.

The invention discloses a couple-part symmetry-degree zero-error positioning device, which comprises a substrate, a positioning assembly, two clamping adjusting assemblies and two pneumatic clamping assemblies; the position of a rotary positioning screw in the positioning assembly is fixed and adjusted by adopting the helical-type self-centering compression way, the two clamping adjusting assemblies and the two pneumatic clamping assemblies realize synchronous and symmetric clamping and adjustment so as to limit the freedom of a couple part in the left-right direction, other degrees of freedom of the couple part are limited by utilizing a front baffle plate, a rear baffle plate and a pressure plate simultaneously, so that the couple part is clamped and positioned. The device utilizes the advantages of a centering clamping way and a synchronous symmetric movement way to avoid the influence of installation error and repetition precision error on the positioning error of the position, so that the zero-error positioning precision requirement of the couple part is realize theoretically. The couple-part symmetry-degree zero-error positioning device is simple in structure and strong in practicability; and moreover, the positioning position of the couple parts also can be adjusted according to real requirement. The device is also applicable to the positioning of multiple couple parts and wide in application range.