88 results about "Form error" patented technology

The invention belongs to the technical field of optical device manufacturing and relates to a method for improving shape accuracy and processing efficiency of an off-axis aspheric mirror, comprising the following steps: (1) designing a rotary aspheric surface as well as a primary and secondary consubstantial structure for the primary body according to the size and the dimension of the off-axis aspheric mirror to be processed, i.e. a secondary body, and determining the amount of the off-axis aspheric secondary bodies to be processed at one time; (2) disposing through holes on a primary body blank piece; (3) placing all secondary body blank pieces into the through holes and fixing on a lathe after integrating into a cylindrical integrated work piece, and processing a spherical surface closest to the rotary aspheric surface on the integrated work piece; (4) generating a processing path of cutting tools based on the shape of the rotary aspheric surface, reprocessing the spherical surface by utilizing an ultra-precision lathe and carrying out form error analysis and compensating processing according to the measured integrated rotary aspheric surface shape. The provided method is simpleand easy to realize, has the advantages of high-efficiency, easy detachability and high shape accuracy and can realize high-efficient processing on an off-axis aspheric surface with high shape accuracy.

The invention provides a three-coordinate measuring method for bevel gear tooth form error; the procedures of the method are that: (1) the stop position of measuring bevel gear tooth form error is defined by calculation; (2) positions of other measuring points on the checking part are defined; (3)the actual tooth face is measured by taking the stop position and the theoretical coordinates of measuring points as object points; (4) the tooth form error is worked out. By applying the method of the invention in the tooth form error measurement, the repeatability error can be controlled below 0.004mm, thereby markedly improving the measuring accuracy and being capable of measuring the involute gear below six-grade accuracy. The trend of the involute form of the measuring result is relatively obvious, based on which the depth of the tooth root and the tooth head can be analyzed. According to the measuring result, the gear-cutting machine is guided to be adjusted, achieving good effects.

The invention discloses a high-spatial-discrimination long-range facial-form detecting device and method. The device comprises a scanning optical head and is characterized in that the scanning optical head comprises a small hole array plate, a beam splitter, a lens array and an array detector, the small hole array plate divides input parallel light beams into a plurality of parallel thin light beams, then the light beams enter the beam splitter, each thin light beam is input to the lens array in a transmission mode through the beam splitter, lens units in the lens array focus the corresponding thin light beams to the surface of an object to be tested respectively, and the light beams reflected by the surface of the object to be tested enter the array detector through the lens array and the beam splitter in sequence. The device is simple in structure and stable in performance, high-space-frequency sampling measuring can be carried out on the surface to be tested, measuring of facial-form errors of high frequency (larger than 1 line/mm) can be expanded, and at least 10 lines/mm can be achieved commonly.

The invention provides an error compensating method for material-increase manufacturing. The method includes the steps that model data of a part are read, and a three-dimensional digital model of the part is established according to triangular face sheets; an independent correction offset is set for each triangular face sheet and determined by a normal vector of the triangular face sheet and the semi-ellipsoidal shape of a sedimentation unit at the position where the triangular face sheet is located; all the triangular face sheets forming the three-dimensional digital model of the part are deflected to the interior of the part according to the set independent correction offsets corresponding to the triangular face sheets, a three-dimensional digital correction model of the part is obtained, and the manifold property of the three-dimensional digital correction model of the part is maintained; and layering and material-increase manufacturing of each layer are directly performed to achieve path control of a sedimentation path according to the three-dimensional digital correction model of the part, and a subsequent material-increase manufacturing craft process is driven. The error compensating method can reduce anisotropy forming errors caused by anisotropy of the size of the sedimentation unit during material-increase manufacturing and increase material-increase manufacturing precision and forming quality.

The invention discloses a partition scanning method for thin-walled part additional material manufacture. According to all entity areas of layering and slicing of a to-be-machined thin-walled part, inaccordance with the medial axis transformation of the boundary of each entity area, whether the area is divided into a plurality of main areas and a connecting area is determined; scanning paths arecalculated for the main areas and the connecting area, wherein a zigzag scanning path is adopted in the main areas, so that a fused powder material is scanned along a scanning line and a slicing and layering contour line finally through a high energy beam to form a thin-walled part slicing layer entity, so that the whole thin-walled part is formed. The control of a processing process is simple, residual stress and distribution thereof can be controlled, forming errors and buckling deformation of the thin-walled part are reduced, and the density of the thin-walled part and the strength thereofare improved.

The invention relates to an evaluation method of flame model reliability, belonging to the technical field of virtual reality science. The invention has the technical scheme as follows: (1) under a relatively stable environment, sampling flame combustion to obtain a real flame video and a simulated flame three-dimensional time-varying model under the state, and capturing a plurality of images at equal time interval in a video and simulation result; (2) comparing the images obtained in step (1), calculating the form error, the color error and the random error of the flame model relatively to the real flame, and combining with user requirements to calculate the demand error of the flame model relatively to the real flame; (3) generating the error function of the flame model by each error item; and (4) according to the error function, analyzing the flame model reliability. In the invention, the visual parameter information of the flame model and parameter information relative to user demands are fully considered, so that a method for evaluating a flame simulation result is provided, the reliability of a simulation result is analysed and a method basis for choosing and improving a modelling method is provided.

The invention discloses a channel coding method improving transmission reliability of a non-line of sight millimeter wave indoor communication system, and brings forward a method that a variable-code-length low-density check code is used to improve communication reliability of a millimeter wave communication system. An error correction system is mainly adopted to generate different-length redundant data on user data having different bit numbers at the same coding rate, the user data and the redundant data are combined to form error correction codes having different code lengths, at least one bit of control information is used in a signaling domain to indicate a selected code length of current transmission, a transmitter selects a code length capable of providing and guaranteeing communication reliability according to various communication channels and quality of a transmission signal, code length information is transmitted to a receiver through control information, and the receiver uses the error correction codes corresponding to the code length to decode the data according to the received control information. The channel coding method effectively improves adaptability of a millimeter wave wireless communication system on a change of the transmission channel, and then transmission reliability of the system is improved.

The method for manufacturing rectangular pipe with sharp corner is characterized by that it uses rolling central line as a diagonal line of formed pipe to make multiple-pass cold-bending symmetrical deformation so that two side ends of steel strip which are made into oblique end face are finally closed on the rolling central line so as to form included angle with 90 deg. of said rectangular pipe. Said method is easy to regulate and operate, small in formed error, weld seam and two side are in symmetrical state, so that its welding effect is good, and its energy consumption also can be reduced.

The invention provides an online zero-adjustment method of a proportional valve, which mainly utilizes a proportional valve control system to feed back a position state signal of a main valve core to judge whether the zero point of the valve core drifts, thereby realizing online accurate zero-adjustment. Since the zero point of the valve is adjusted through the position feedback signal of the main spool, no matter whether the natural zero point of the return spring of the proportional valve is offset or not, the proportional valve can always be guaranteed to work near the real zero point, which overcomes the traditional method due to the mechanical deformation of the spring. The signal error ensures the stability of the proportional valve, and realizes online debugging, which reduces the maintenance workload, does not require investment and purchase of special debugging equipment, can save 8 hours of adjustment and testing time each time, and can reduce downtime by 48 hours throughout the year.

The invention discloses an urban train fixing and reconnecting device for realizing automatic protection. The device is provided with automatic reconnecting linkers M and T; a relay J1 is connected between a contact pin (C16) of the automatic reconnecting linker M and the positive input end of a power supply; a relay J2 is connected between a contact pin (C19) and the ground; a relay J3 is connected between a contact pin (C26) of the automatic reconnecting linker T and the positive input end of the power supply; a relay J4 is connected between a contact pin (C29) and the ground; and normally-closed contacts J1-1, J2-1, J3-1 and J4-1 of the relays J1, J2, J3 and J4 are connected to a train safety loop wire. The device has a simple structure, low cost and easy realization; when a train is fixed and reconnected, the device can carry out automatic monitoring and control on a marshalling form and a reconnecting option switch; when the marshalling form is wrong or the reconnecting option switch is out of place, the safety loop wire cannot be established between the reconnecting trains, so the hidden trouble of accident is eliminated and safe and reliable operation of the train in reconnection is ensured.

A method for designing linearity of a mounting surface for a rolling linear guide of a precision machine tool includes the steps of first, expressing a form error of a fitting characteristic surface by means of a modal base function based method, and generating a random error sample within a given linearity tolerance; second, establishing a finite element based form error propagation model according to the generated random error sample by means of finite element software ANSYS, acquiring a fitting error of the rolling linear guide by means of finite element analysis, using the Monte-Carlo method to input all random errors generated within a given tolerance zone, into the finite element based form error propagation model and to calculate the random errors so that a post-fitting linearity tolerance is obtained, and establishing a guide fitting tolerance analysis model; and third, on the basis of the guide fitting tolerance analysis model, designing the linearity of the mounting surface for the rolling linear guide according to the concept of cyclic search. The method has the advantages that dependence on experiences is reduced, reliable theoretical guidance is provided for the design of the linearity of the guide mounting surface, product development time can be shortened, cost can be reduced, and economic benefit can be increased.

The invention discloses a data auxiliary positioning method and device, computer equipment and a storage medium, and the data auxiliary positioning method comprises the steps: screening at least one abnormal record in a positioning time period based on an abnormal data record table; obtaining an abnormal data landing table corresponding to the abnormal record based on the error information; acquiring a target data landing table for recording the data label based on the data label; if the abnormal log corresponding to the abnormal record exists in the interface log database, extracting target field content corresponding to at least one specified field from the abnormal log; filtering the target field content by adopting a preset screening rule, and if a filtering result is a reporting processing result, forming error reporting information; and forming the error reporting information, the abnormal data landing table and the target data landing table into auxiliary positioning data, and sending the auxiliary positioning data to the client. The data auxiliary positioning method can improve the positioning efficiency and positioning accuracy of abnormal data.

The invention provides a multi-point active loaded aircraft panel prestressing shot blasting tooling and method. The multi-point active loaded aircraft panel prestressing shot blasting tooling is composed of a rigid frame, a longitudinal beam and a plurality of puncher pins. A linear guide rail is designed on the frame, the longitudinal beam is mounted on the linear guide rail, and the puncher pins and a compression mechanism are mounted on the longitudinal beam, wherein the height of each puncher pin can be subjected to digital control adjustment by a computer, and the compression mechanism is used for fixing a wall panel. Each puncher pin is equipped with an integrated digital-controlled driving decelerating motor, the motor rotates to drive a guide screw, the height adjustment of each puncher pin body in the axial direction is achieved, and each puncher pin body can be locked at any position. Compared with a traditional prestressing shot blasting fixture, the digital-controlled puncher pins can form a pre-bending type face to achieve pre-bending of a wall panel piece with any curvature. The multiple puncher pins make the wall panel to bear prestress more evenly, and the phenomenon of partial distortion caused by single point applying force can be avoided effectively. In the forming process of a blasted shot, the heights of the utilized puncher pins can be adjusted in real time according to the deformation situation of the wall panel, and thus the accuracy of forming of the blasted shot is improved. After the blasted shot is formed, the tooling can serve as a test profiling to test the forming error of a curved wall panel.

The invention provides a system for automatically detecting and diagnosing flexural deformation of axial line of workpiece. When the workpiece is driven by a rotation control module to rotate around a rotation axial line, the system records the radial pulsation value of the workpiece and the rotation angle value of the workpirce, screens out the data generated by the form error of the sections, such as ellipse, triangle, bulge, burr and the like after the filtration treatment of an error diagnostician system, and extracts the measurement data generated by the flexure error of the axial line of the workpiece, thereby generating the standard space model of the flexure of the axial line, so as to complete the task of automatically detecting and diagnosing flexural deformation of axial line of the workpiece.

The invention discloses a gear shaving profile error prediction method, which comprises the following steps of: introducing a gear shaving mounting error into a gear shaving motion coordinate system,constructing new coordinate conversion, deducing and calculating a compensation displacement amount caused by the gear shaving mounting error, and enabling the mode of the compensation displacement amount at a normal component vector of a contact point to be a tooth profile cut depth caused by the gear shaving mounting error. And elastic-plastic press-cutting deformation of gear shaving surface contact is given based on the contact mechanics, and the actual press-cutting deformation of gear shaving is calculated by comparing the ultimate strength of the material. And comprehensively considering the gear shaving installation error tooth profile cutting depth and the gear shaving actual pressing and cutting deformation to establish a gear shaving tooth profile error prediction model. By means of the method, prediction of the gear tooth form error of the shaved workpiece can be accurately achieved, the tooth surface precision and the machining efficiency can be effectively improved, and targeted technological guidance is provided.