1218 results about "Tooth surface" patented technology

The invention relates to the technical field of numerical control machining monitoring, in particular to a tooth deviation high-precision monitoring system in a tooth cutting machining process, which comprises an online measurement module, a dynamic compensation module, a deviation calculation module and a result output module which are in signal connection with a numerical control system of a tooth cutting machine tool, the online measurement module, the dynamic compensation module, the deviation calculation module and the result output module are integrated on the processing element; the processing element is used for obtaining workpiece design parameters and constructing a theoretical workpiece model, the online measurement module is used for collecting tooth surface point cloud data in real time in the machining process, the dynamic compensation module is used for correcting vibration errors and temperature errors of the point cloud data, and the deviation calculation module is used for quantifying tooth surface deviation values. And the result output module is used for generating an early warning signal and a dynamic correction instruction and executing system self-calibration. The device and a numerical control system form a closed loop of machining, monitoring, correction and remachining, and finally high-precision real-time monitoring and dynamic correction of tooth deviation are achieved.

The invention relates to the technical field of computers, discloses a tooth three-dimensional precision correction method and system based on multi-source oral data fusion, and aims to solve the problems of low registration precision, serious geometric distortion and lack of function oriented optimization of multi-modal oral data in the prior art. The method comprises the following steps: synchronously obtaining intraoral scanning, CBCT and face three-dimensional point cloud data; carrying out format conversion, denoising and grid simplification preprocessing; tooth surface morphology, root canal anatomy and soft tissue contour features are extracted and coded into uniform feature tensors; and multi-modal data space alignment is realized through staged rigid and non-rigid registration. By means of the scheme, the multi-source data fusion precision and the tooth form restoration accuracy are remarkably improved, full-process automatic efficient processing is achieved, and the clinical real-time performance and high-precision diagnosis and treatment requirements are met.

The invention discloses a tooth profile grinding wheel thermal drift modeling and wear life prediction method and system. The method comprises the four stages of thermal drift path network construction, drift differentiation feature extraction, irregular fragmentation recombination and dynamic judgment feedback. A tooth surface multi-region temperature response sequence is collected, a thermal drift path network is established, and a drift differentiation feature set is generated by using a multi-period path evolution relationship so as to distinguish short-period thermal disturbance and trend drift interference; and irregular recombination and energy constraint optimization are carried out on the path based on the thermal response structure boundary to form a response structure unit with thermal-force coupling association. The system further achieves judgment sequence self-learning according to an energy feedback and weight updating mechanism, and therefore the abrasion state and remaining life prediction result of the tooth profile grinding wheel is output. According to the method, dynamic correction of grinding thermal response behaviors and intelligent life evaluation are achieved.

The invention discloses an artificial intelligence-based periodontal state evaluation method, which comprises the following steps of: acquiring multi-modal tooth data which comprises a tooth surface image and a local blood vessel network image of an oral cavity; preprocessing the multi-modal tooth data, and performing cross-modal registration by using a registration module to obtain a registered tooth surface image and a registered blood vessel network image; extracting multi-dimensional features of the registered blood vessel network image through a first feature extraction module, wherein the multi-dimensional features comprise spatial morphological features, topological connectivity features and hemodynamic features of blood vessels; extracting macroscopic morphological features and lesion local features of the registered tooth surface image through a second feature extraction module; performing cross-modal fusion on the multi-dimensional features, the macroscopic morphological features, the local lesion features and the clinical data to obtain fusion features; and outputting a periodontal state evaluation result based on the fusion features, thereby facilitating improvement of periodontal state evaluation accuracy and periodontal disease early warning capability.

The invention relates to a method and device for measuring pitch deviation based on a line laser sensor, and the method comprises the following steps: S1, calibrating the position of the line laser sensor, and obtaining the coordinate value of a coordinate system of the line laser sensor in a measurement coordinate system; s2, installing a tested gear; s3, adjusting the relative position of the line laser sensor and the measured gear; selecting a measured position in the tooth surface area of the gear teeth of the measured gear, adjusting the position of the line laser sensor, and recording the sum of the offset of the adjusted line laser sensor relative to the center of the measured gear along the x axis and the y axis in the effective measurement range of the line laser sensor at the measured position; s4, performing zero returning operation on the angle sensor of the rotating shaft of the tested gear; and S5, controlling the detected gear to rotate along the center line of the detected gear. According to the method and the device, the pitch deviation can be measured in a non-contact mode, excessive calibration and leveling are not needed before detection, and the measurement efficiency and the measurement precision are both improved.

The invention discloses a design method of a complex shape modifying and finishing wheel and a honing wheel for internal meshing powerful gear honing, and relates to the technical field of machine manufacturing. The method comprises the following steps: establishing a trimming wheel tooth surface numerical model, and judging whether the modification amount of the trimming wheel tooth surface numerical model meets the modification requirement or not; if yes, establishing a space coordinate conversion relation and a conjugate meshing equation of the dressing wheel and the honing wheel, and establishing a honing wheel tooth surface numerical model in combination with the dressing wheel tooth surface numerical model; according to the space coordinate conversion relation between the workpiece gear and the honing wheel and the honing wheel tooth surface numerical model, a complex modification workpiece gear tooth surface numerical model is established, and whether the modification amount of the complex modification workpiece gear tooth surface numerical model meets the modification requirement or not is judged; and if yes, a dressing wheel three-dimensional solid model and a honing wheel three-dimensional solid model are established according to the dressing wheel tooth surface numerical model and the honing wheel tooth surface numerical model respectively. According to the method, precise design and verification of the complex shape modifying and finishing wheel and the honing wheel for powerful gear honing can be achieved.

The invention belongs to the field of data processing, particularly relates to a wind turbine generator gear box tooth surface strength optimization method considering multi-working-condition load distribution, and aims to solve the problem that the optimization effect is affected due to the fact that strength optimization checking is carried out only for a single working condition in the prior art. The method comprises the following steps: acquiring working condition data of the gearbox under various preset working conditions; load spectrum decoupling processing is conducted on the working condition data, a dynamic load distribution matrix synchronous with the tooth surface meshing period is determined, stress field conversion is conducted on the dynamic load distribution matrix, and a tooth root bending stress field and a tooth surface contact stress field are obtained; inputting the tooth root bending stress field and the tooth surface contact stress field into a pre-constructed double-constraint optimization model to obtain a tooth surface strengthening parameter tensor output by the model; and inputting the tooth surface strengthening parameter tensor into a preset process mapping system. Based on the method provided by the invention, the multi-working-condition operation data of the gearbox are synchronously obtained for optimization calculation, and the limitation of traditional single load analysis is broken through.

The utility model discloses a closing clip capable of preventing tissue from being torn, and belongs to the field of medical hemostatic clips. The closing clamp capable of preventing the tissue from being torn comprises a first clamping arm and a second clamping arm, the near ends of the first clamping arm and the second clamping arm are connected through a connecting part, and the far end of the first clamping arm and the far end of the second clamping arm are respectively provided with a locking structure which can be buckled and locked together. The clamping faces of the first clamping arm and the second clamping arm are each divided into an anti-skid tooth face and a clamping smooth face in the width direction, and the anti-skid tooth face and the clamping smooth face of the first clamping arm and the anti-skid tooth face and the clamping smooth face of the second clamping arm are arranged in a one-to-one correspondence mode or in a crossed correspondence mode. According to the utility model, the clamping surfaces of the two clamping arms of the closing clamp are divided into the anti-slip tooth surfaces and the clamping smooth surfaces, so that the clamping pressure of the closing clamp on vascular tissues during closing is reduced, unnecessary damage to the tissues in the process of closing the tissues is effectively avoided, and hemostasis failure caused by tearing of the vascular tissues is prevented.

The invention provides a gear peeling time-varying meshing stiffness prediction method and system based on a back propagation neural network, and the method comprises the steps: considering a tooth surface peeling fault based on a gear tooth bearing contact analysis method, and constructing a helical gear pair time-varying meshing stiffness calculation model; a real irregular tooth surface peeling area is fitted by adopting a least square ellipse fitting method to obtain an ellipse appearance representation, any peeling position is completely described through six key geometric parameters, the geometric parameters of the ellipse appearance are systematically traversed and fitted, and diversified peeling appearance samples are generated. Introducing a tooth profile deviation matrix corresponding to the peeling morphology sample into a tooth surface bearing contact analysis model, and constructing a training data set; and constructing a back propagation neural network model of multiple hidden layers, and performing end-to-end training by using the training data set, so that the back propagation neural network model learns a nonlinear mapping relationship from geometric parameters to a time-varying meshing stiffness curve, thereby predicting the time-varying meshing stiffness under any peeling morphology.

The invention provides a gear contact fatigue life prediction method considering macro-micro geometric parameter influence. The method comprises the following steps: firstly, establishing a tooth surface contact-dynamics analysis model considering macro-micro geometric parameter influence, and calculating tooth surface dynamic load distribution; secondly, establishing a calculation model of the stress on the surface and below the surface of the gear considering the influence of lubrication and surface roughness, and calculating the oil film pressure and the stress on the surface and below the surface of the gear; and finally, establishing a gear contact fatigue life prediction model considering the influence of macro and micro geometric parameters, and calculating the contact fatigue life of the gear. According to the method, the influence of the rigidity change of the gear on the contact fatigue life of the gear is considered, the contact fatigue life of gears with different web structures is predicted, and the deviation between the contact fatigue life obtained through theoretical calculation and the actual contact fatigue life is reduced. Meanwhile, the method considers the influence of the error on the contact fatigue life of the gear, so that the prediction of the contact fatigue life of the gear with the modification and the error is realized.

The invention relates to the technical field of angle measurement, in particular to an angle measurement device. The device comprises a gear transmission mechanism, an angle detection mechanism and two anti-backlash mechanisms, the gear transmission mechanism comprises a driving gear and two follow-up gears; the angle detection mechanism comprises two follow-up end angle sensors. According to the angle measuring device provided by the invention, before the driving gear is started, the two anti-backlash mechanisms apply pre-tightening torques in opposite directions to the two follow-up gears respectively, so that the two follow-up gears are in contact with the left side tooth surface and the right side tooth surface of the driving gear respectively, and then the backlash in the tooth side when the driving gear is started in the forward direction and the reverse direction is eliminated; therefore, a bidirectional transmission preparation state without return stroke errors is realized. Therefore, the problems that due to the fact that a certain gear backlash is reserved between meshing gears, power can be transmitted to the output end only after the gear backlash is eliminated, and time delay and angle deviation are generated on signals detected by an angle sensor are solved.

The invention provides a gear tooth surface precision detection method based on a deep learning network, a medium and equipment, and mainly solves the problem of insufficient model generalization ability caused by scarcity of real labeled data and domain difference in an existing method. The method comprises the following steps: collecting a plane workpiece image marked with a roughness level as a source domain data set, and pre-training an intelligent detection model; based on a gear shaping machining meshing motion relation, establishing a tooth surface morphology geometric simulation model, and generating virtual gear tooth surface images of different roughness grades; extracting a real gear tooth surface area image as a target domain sample; a domain adaptation method based on clustering optimal transmission is adopted, the feature distribution difference between a source domain and a target domain is calculated and minimized, model parameters are optimized, and self-adaptive migration of a feature space from a plane image to a gear tooth surface is achieved. According to the method, virtual sample generation and a domain adaptation technology are combined, so that the data acquisition cost is effectively reduced, and the detection precision and the model generalization ability under the small sample condition are remarkably improved.

The invention discloses a gel composition for improving compatibility and gelling speed of a tooth whitening product. The gel composition comprises whitening gel and a catalyst, respectively filling the whitening glue and the catalyst into a double-barrel injector; when the tooth whitening gel is used, the push rod is pushed, the whitening gel and the catalyst in the double-tube barrel are squeezed out at the same time and mixed at the mixing head to form the tooth whitening gel capable of being smeared on the tooth surface of a patient, and the pH value of the tooth whitening gel is 7.5-10.0. The catalyst comprises potassium salt or strontium salt, sodium fluoride, glycerol, cross-linked polyacrylamide gels, strong alkaline substances, essence and water; the whitening gel comprises a hydrogen peroxide solution, a cross-linked polyacrylamide gel, glycerin, essence and water. The cross-linked polyacrylamide gel is adopted, the gel is resistant to strong-alkalinity and high-pH environment and various inorganic salt ions such as fluoride, sylvite or strontium salt, the prepared gel is stable in form and good in compatibility, the gel preparation process is simple, the gel is rapidly swelled when encountering water and does not huddle, and long-time standing is not needed.

The invention provides an end face logarithmic spiral oscillating tooth transmission device with an adjustable backlash. The device comprises a transmission assembly. The shell allows the movable teeth to pass through; the lubricating assembly comprises an elastic telescopic piece and an abutting assembly, the elastic telescopic piece is arranged in the lubricating hole and can abut against the hole wall of the lubricating hole, one end of the abutting assembly is connected with the end of the elastic telescopic piece, the other end of the abutting assembly abuts against the shell, and the face, abutting against the shell, of the other end of the abutting assembly is an inclined face; wherein the area where the movable teeth rotate in the circumferential direction comprises a top area and a bottom area, and when the movable teeth drive the lubricating assembly to rotate in the bottom area, the lubricating assembly recovers deformation and extends so as to push the abutting assembly to get close to the inclined face, and a space is released for lubricating oil to enter the lubricating hole; when the movable teeth drive the lubricating assembly to rotate in the top area, the lubricating assembly is compressed by the inclined face, so that the elastic telescopic piece is shortened, and the abutting assembly moves into the lubricating hole to extrude lubricating oil in the lubricating hole and discharge the lubricating oil to the meshing tooth face of the inner gear ring.

A portable, multimodal dental diagnostic device for assessing the vitality of the dental pulp, consisting of: a detachable diagnostic component comprising a variety of probes, including the following: a heat probe configured to deliver controlled heat stimuli to a tooth surface and measure the heat response of the dental pulp; an electrical probe configured to deliver low-voltage electrical pulses to the tooth surface and measure the electrical impedance of the dental pulp; and an optical probe configured to assess blood oxygen saturation and microcirculation in the dental pulp using near-infrared light; a microcontroller unit configured to process sensor data from the thermal probe, the electrical probe and the optical probe, to calibrate measurements based on the oral base temperature and the ambient conditions, to aggregate multimodal sensor data and to control the operation of the thermal probe, the electrical probe and the optical probe; a cloud platform configured to receive and store aggregated sensor data, run artificial intelligence algorithms to analyze multimodal sensor data and generate diagnostic insights that include vital signs and diagnostic probabilities; a user application that is communicatively connected to the cloud platform and configured to wirelessly receive aggregated sensor data, display detailed diagnostic reports with vital signs and trends to the user, integrate with electronic health data systems, and issue alerts in case of abnormal readings; a wireless communication module connected to the microcontroller unit, configured to transmit the aggregated sensor data to the cloud platform; a display interface configured to show real-time feedback from the probes, including vitality assessments and sensor readings; and a main body containing the microcontroller unit, a rechargeable power supply and the display interface, wherein the rechargeable power supply can be charged via the current provided through a charging port on the main body, and wherein the main body is also equipped with on / off and start / stop switches; the device is configured to provide a non-invasive, quantitative real-time analysis of dental pulp health by combining physiological responses from thermal, electrical, and optical measurements.

The invention discloses a method for calculating the strength of an end face tooth coupling of an energy storage centrifugal compressor, relates to a method for calculating the strength of an end face tooth coupling, and aims to solve the problem that a method for accurately judging whether the strength of the end face tooth coupling of the compressor is qualified or not by a conventional end face tooth calculation and checking method does not exist at present. The method is implemented according to the following steps that firstly, axial component force generated when the end face teeth transmit torque is obtained; 2, the axial expansion difference of the end face teeth, the main shaft and the screw at the working temperature is calculated, and the actual pre-tightening force of the screw during unit operation is calculated; 3, impeller thrust generated by the front and back pressure difference of the impeller is calculated, the effective tooth surface area of the end face teeth is calculated, and the end face tooth root bending stress, the end face tooth maximum extrusion stress and the end face tooth axial tensioning force safety coefficient of the centrifugal compressor are calculated; and 4, judging the strength of the end face tooth coupling of the energy storage centrifugal compressor. The invention belongs to the field of end face tooth coupling checking.

The invention discloses a tooth profile grinding three-dimensional heat distribution reconstruction and structure evaluation method and system, and the method comprises the steps: building a three-dimensional tooth surface discrete grid through combining a grinding wheel motion track, a tooth surface geometric morphology and a grinding wheel macrostructure, and generating a contact unit set with a time label through track mapping and path continuity; grinding energy input and grinding wheel abrasive particle distribution difference are combined, a weighted energy diagram is constructed, a directed energy transfer path is formed under a grid adjacency relation, an energy flow mode is obtained through iterative diffusion, a time sequence convolution and offset extraction mechanism is introduced, a thermal migration disturbance condition reflecting local thermal diffusion abnormity is generated, the thermal migration disturbance condition is coupled with a three-dimensional grid, and a three-dimensional model is obtained. And driving an unsteady state heat conduction solver to obtain a tooth surface heat distribution field, extracting a tooth surface potential sensitive area set by using a structure evaluation operator, and realizing comprehensive evaluation of heat-force response and structure risks.

The invention belongs to the technical field of metal material mechanical property research, and discloses a gear shot peening tooth surface residual stress calculation method and system.The method comprises the steps that a shot speed calculation model in the gear shot peening process is built, shot peening process analog simulation is carried out, and dynamic information of collision between shots and a tooth surface is output; the projectile speed is converted from a machine tool coordinate system to a local coordinate system; establishing a sprayed target plate model and a projectile model, dividing grids, and assembling the grid-divided projectile model and the sprayed target plate model to construct a random multi-shot finite element geometric model; and performing finite element simulation calculation on the random multi-shot finite element geometric model, and outputting residual stress distribution of the gear. According to the method, computational fluid mechanics and a discrete element method are coupled, a high-precision calculation model of the shot speed in the gear shot blasting process is constructed, the forming mechanism and distribution characteristics of the tooth surface residual stress in the actual shot blasting process are effectively reflected, and the method is good in economical efficiency, high in simulation precision, high in process executability and closer to engineering practice.

The invention relates to the field of orthodontics, in particular to a device for controlling palatal root movement of anterior teeth of an upper jaw and a manufacturing method. According to the device, the traction arm and the traction ring which extend to the palatal side of the anterior maxillary teeth are additionally arranged on the basis of the transverse palatal bar and are matched with the traction buckle of the anterior maxillary teeth to guide orthodontic force to act below a tooth impedance center, so that root control movement which is difficult to achieve by a traditional orthodontic method is realized, bending torque on an arch wire or placing other root control devices is not needed, and the whole device is simpler and more attractive; in addition, the device part is manufactured by adopting a 3D printing technology, firstly, tooth and intraoral soft tissue data of a patient are obtained by scanning the interior of an oral cavity, then the oral scanning data are matched with CBCT, a specific device is designed by using software, finally, a finished product is directly printed in a 3D manner, the transverse palatal bar and the traction buckle are completely matched with the tooth surface by adopting the 3D printing technology, and the comfort level is high.

The invention relates to the technical field of industrial visual inspection and intelligent manufacturing, and discloses a complex tooth surface structure-oriented bevel gear surface video defect detection method, which comprises a video data acquisition and preprocessing step, a video time sequence modeling branch construction step, a super-image space expression branch construction step and a double-branch fusion prediction step. And a reasoning and detection output step. According to the invention, for the bevel gear tooth surface with complex curvature, strong light reflection and tiny defect characteristics, a two-way detection architecture in which a video time sequence modeling branch and a super-image space expression branch are fused is constructed; cross-frame dynamic defect features are captured by using a video transformer network based on a sliding window, and local space texture perception is enhanced through super-image stitching and a pre-training network, so that stable and accurate identification of micro defects and cross-frame evolution defects is realized under the background of complex tooth surface reflection and structure interference; and the method has relatively high detection robustness and comprehensive performance.

The invention provides a gearbox defect detection method and device based on multi-scale feature extraction, and the method comprises the steps: carrying out the preprocessing of multi-source data, carrying out the feature extraction of the preprocessed multi-source data through employing a plurality of convolution kernels, and obtaining multi-scale features. And carrying out feature fusion on the multi-scale features by adopting an attention mechanism. And performing feature reconstruction on the fused features by using a feature reconstruction model to obtain reconstructed features. And calculating a reconstruction error according to the reconstructed features, and identifying gear box defect features according to the reconstruction error. The first convolution kernel is used for capturing fine scratches on the tooth surface, the second convolution kernel is used for identifying abnormal meshing of the gear, and the third convolution kernel is used for detecting whether defects such as bearing outer ring peeling and tooth surface fatigue peeling exist or not. According to the method, the operation state of the gearbox can be monitored in an all-around mode, the accurate gearbox defect recognition result is generated, the cross-working-condition detection precision is improved, process automation is achieved, the operation reliability of the gearbox is remarkably improved, and the service life of the gearbox is remarkably prolonged.

The invention discloses a modeling method for a thermally induced tooth surface error of a spiral bevel gear. The modeling method comprises the following steps: S1, establishing a motion coordinate system of a cradle type gear milling machine; s2, according to the motion coordinate system of the cradle type gear milling machine and the gear meshing equation, a tooth surface equation machined through a generating method is constructed; s3, performing grid discretization on the tooth surface of the gear to be machined, and solving the tooth surface equation by adopting a rotary projection method and a genetic algorithm to obtain three-dimensional coordinates of discrete points of the tooth surface of the gear to be machined; s4, establishing a motion coordinate system of the numerical control gear milling machine; carrying out equivalent conversion on the motion coordinate systems of the cradle type gear milling machine and the numerical control gear milling machine to obtain a mapping relation between each motion axis coordinate of the numerical control gear milling machine and the tooth surface discrete points of the gear to be machined; and S5, a thermally induced tooth surface error model is constructed, a tooth surface rotation calibration method is adopted to enable the midpoint of the theoretical tooth surface to coincide with the midpoint of the error tooth surface so as to correct the tooth surface error of the gear to be machined, and an error vector is projected in the normal direction so as to obtain the tooth surface error value of each discrete point.

The present disclosure discusses techniques for fabricating bite interference elements within polymeric dental appliances. The techniques disclose at least one polymeric shell that includes a number of cavities shaped to fit over a patient's teeth. The polymeric shell includes an occlusal appliance surface shaped to fit over an occlusal tooth surface of the patient. One or more bite interference elements are formed within the occlusal appliance surface, and each bite interference element includes a partially disc-shaped feature extending radially away from the occlusal tooth surface when worn by the patient.

In one aspect, a device for imaging an oral cavity is disclosed. The device incorporates a head and an elongate body, the head having a base portion, first and second wing structures, and first and second image sensors. The first and second image sensors are mounted to the first and second wing structures and enable imaging of the user's oral cavity. The wing structures enable simultaneous imaging of multiple tooth surfaces simultaneously and may aid in positioning of the head of the device.

This invention relates to the field of booms, and discloses a rotary drive mechanism, a boom, and engineering machinery. The rotary drive mechanism includes an annular piston (10) and a stator. The annular piston (10) is provided with piston teeth having protruding curved tooth surfaces and piston teeth having inclined flat tooth surfaces. The stator is provided with stator teeth having protruding curved tooth surfaces and stator teeth having inclined flat tooth surfaces. The annular piston (10) can be driven to move axially relative to the stator. Through the above-described technical solution, the combination of the meshing of curved tooth surfaces and the meshing of flat tooth surfaces can ensure smooth transmission in the initial meshing stage, reduce noise, and allow the subsequent meshing stage to convert axial movement into uniform rotation, providing a more stable torque output.

The invention relates to the technical field of valve manufacturing, and discloses a special counter sinking tool for valve manufacturing, which comprises a supporting and positioning mechanism, and the top end of the supporting and positioning mechanism is connected with a counter sinking mechanism, an aperture grinding mechanism and a linkage mechanism. A tooth surface rod of the second positioning rack is just engaged with the tooth surface of the second positioning gear, so that the tooth surfaces of the two first positioning gears respectively drive the two first positioning racks and the lifting table to lift, and a grinding seat connected to one side of the lifting table is stably contacted with a countersinking working surface; at the moment, when the positioning shaft and the cutter rotate, the polishing seat and the positioning seat are driven to rotate along the positioning frame, so that the polishing seat fixed at the top end of the positioning seat stably contacts and polishes burrs of a countersink, the burrs are treated in time after the countersink is finished, subsequent procedures are avoided, the machining quality of the valve body is improved, and the assembling difficulty of the valve body is reduced; the connection strength is improved.

An electric fishing reel comprises a reel main body that comprises a left frame and a right frame and side plates covering the left and right frames, an operating part that is provided on a side of the left frame or a side of the right frame and is rotatable, a handle shaft of the operating part, a drive gear that comprises a cylindrical portion and a tooth surface and is rotatably frictionally coupled to the handle shaft, and a drag washer that is non-rotatably fitted to the handle shaft and is provided at an end of the drive gear on a side in a direction of the handle shaft, in which a protruding portion protruding in a direction of the drive gear from an inside of the side plate covering the left frame or the right frame is provided, and an end of the protruding portion is formed to be separated by a distance equal to or less than 3.0 mm with respect to an upper surface of the drive gear as viewed in the direction of the handle shaft.

The invention discloses an electric toothbrush and a control method and device thereof, and relates to the technical field of electric toothbrushes, the electric toothbrush comprises a brush head, in the control method of the electric toothbrush, when the electric toothbrush is in a power-on state, the contact pressure between the brush head and the tooth surface and the position information of the brush head are obtained; the vibration intensity of the brush head is adjusted according to the contact pressure; the current cleaning area is determined according to the position information, the brush head is controlled to move according to the corresponding movement mode based on the current cleaning area so that the movement track of the brush head can be matched with the current cleaning area, and the movement mode comprises any one or more combinations of a low-frequency vibration mode, a high-frequency vibration mode, a rotation mode and a reciprocating swing mode. The cleaning effect of the electric toothbrush is improved, and therefore the user experience feeling is improved.

The invention relates to the technical field of mechanical manufacturing and machining, in particular to a dressing wheel and honing wheel design method for improving contact line stability in the gear honing machining process. Based on workpiece gear parameters, a left and right tooth surface mathematical model is established, a honing process space coordinate conversion relation is established, a conjugate meshing relational expression is derived by combining the relative slip speed of meshing contact points and a normal vector, and a tooth surface contact line model is established; and the calculation modeling of the two-dimensional projection of the left and right tooth surface contact lines, the projection intersection point position and the variation under the same rotation angle is realized. And a honing wheel dressing contact line model under dressing wheels with different tooth numbers and a tooth surface contact line intersection projection model in the dressing and honing process under the tooth number difference are established. A honing wheel and variable tooth number dressing wheel design method is provided, and geometric and technological parameters of the honing wheel and the variable tooth number dressing wheel are determined; and a trimming and honing two-degree-of-freedom conjugate meshing relation and a modified tooth surface numerical model are constructed and verified, discretization and point cloud processing are conducted on the model, high-precision tooth surface point cloud is obtained, and accurate machining of a trimming wheel and a honing wheel is guided.

The utility model relates to the field of cup covers, in particular to a cup cover with a telescopic straw, which comprises a cover body, a vertical channel arranged on the cover body, a straw body movably arranged in the vertical channel, a positioning plate arranged on the straw body, a guide rail transversely arranged on the positioning plate, a rotating disc rotationally arranged on the cover body, and an eccentric block arranged on the rotating disc. The eccentric block is connected with the guide rail in a matched mode, a rotary cover is rotationally connected to the cover body, an arc-shaped tooth face is arranged on the rotary cover, and a gear transmission mechanism is arranged between the arc-shaped tooth face and the rotary disc. The utility model solves the problem that the extension length of the straw cannot be adjusted, so that the straw is inconvenient to carry, store and transport.