108results about How to "Improved accuracy and stability" patented technology

The invention discloses a two-degree-of-freedom equal-diameter sphere pure-rolling parallel rotating mechanism and relates to the technical field of robots, precise instruments, equipment and machinery manufacturing. The mechanism is mainly formed by a motion platform, a fixed base and motion branch chains and can implement an effect that the motion platform takes the two-degree-of-freedom equal-diameter sphere pure-rolling parallel rotation around the fixed base. More than three motion branch chains are connected between the motion platform and the fixed base by motion pairs; each motion branch chain comprises more than two connecting rods; and each motion branch chain is of a symmetrical structure and comprises two or a plurality of motion pairs to form more than four degrees of freedom. The rotating mechanism provided by the invention has the advantages that the motion platform has a large working space; the structure is compact; stiffness is high; the mechanism does not include redundant constraining, mutual internal stress does not exist among the motion branch chains and accuracy stability is high; and the two-degree-of-freedom equal-diameter sphere pure-rolling parallel rotating mechanism has the simple structure and is convenient to install. The advantages enable the rotating mechanism to have wide application in the field of a high-performance pointing device.

The invention discloses a wireless indoor locating method based on an access point stability degree. The method comprises the steps that 1, a sampling point is selected indoors, offline collection is carried out on a mobile terminal N times at the sampling point, and the RSS data of all access points are adopted as RSS data samples; 2, the stability degree of each access point is calculated according to the RSS data obtained through multi-time offline collection; 3, all the access points are ranked from big to small according to the stability degree; 4, the first k access points with the high stability degree are selected, and a fingerprint map database is built for the RSS data received by the selected access points in the RSS data samples; 5, the RSS data received by a position to be detected in real time are matched with the RSS data in the fingerprint map database, and therefore locating is achieved. According to the method, the influence of the environment on locating errors can be reduced, and the locating stability and precision are improved.

The invention, which belongs to the field of error compensation of a numerically-controlled machine tool, provides a modeling and compensation method of a radial thermal drift error of a spindle of ahorizontal numerically-controlled machine tool. Two thermal drift errors along the radial direction of a spindle of a umerically-controlled machine tool and corresponding key point temperatures are tested; on the basis of a thermal tilt deformation mechanism of the spindle, a thermal inclination angle of the spindle is obtained and the correlation between the thermal inclination angle and the temperature difference between the left side and the right side of a spindle box is analyzed; according to the positive or negative situation of the thermal drift errors of the tested two points and stretching or contraction situations of the left side and right side of the spindle box, a thermal deformation situation of the spindle is classified and thermal drift error models under various thermal deformation attitudes are established; the influence on the model prediction result by the structural dimension of the machine tool is analyzed; and during real-time compensation, the thermal deformation attitude of the spindle is automatically determined based on the temperatures of the key points and the spindle is compensated by selecting a corresponding thermal drift error model automatically. Therefore, the determination of the thermal deformation attitude of the spindle of the numerically-controlled machine tool is realized during the processing process; and on the basis of the thermal deformation mechanism, the radial thermal drift error of the spindle is predicted.

Using heater and control unit carries out constant heating for wall body to be tested by using plane heat source in ordinary power so as to form a local steady even heat flow in area to be measured. Thus, wall body is tested under manmade steady heat transfer state. Then, temperatures inside and outside wall, heat-flow density and ambient air temperature is itinerant connected. The said heat-flow density is heat-flow density passing through external surface of wall from inside wall to outside wall in area to be tested. Then, comparison and analysis are carried out between the collected data and sample database of heat transfer coefficient of wall body stored in computer and built in advance so as to obtain heat transfer coefficient of wall body finally. Advantages are: preventing influences from surrounding weather, and heat storage and emission of wall body self, good adaptability to climatic environment, short test time, high precision, low cost etc. The invention is suitable to southward with low difference in temperature between indoor and outdoor.

The invention relates to a mask plate used for evaporation and a method manufacturing method thereof. The mask plate comprises a plate frame and a mask plate that are fixed on the plate frame. A plurality of deposition holes are regularly arranged in the mask plate. The deposition holes are disposed in the centre of the mask plate. At least a row of cushion holes are disposed outside of the deposition holes. The cushion holes are parallel to the deposition holes. According to the manufacturing method, the deposition holes in the mask plate do not deform after a manufacturing process of the mask plate used for evaporation is completed. The effect is more remarkable when the method is used for producing a large-size mask plate used for evaporation, so that precision of the mask plate can be increased effectively, a manufacturing precision of an OLED display screen particularly a large-size OLED display screen is increased significantly and manufacturing cost is reduced.

The invention relates to a retro-reflection grating scale measurement system and an application thereof. The system includes a grating scale measurement probe and a grating, wherein the grating scale measurement probe includes a light source, a signal output unit, a measurement unit and a retro-reflection unit. Light beams emitted by the light source enter the measurement unit and then strike on the grating in a non-Littrow angle after exiting the measurement unit. The light beams subjected to optical grating diffraction enter the retro-reflection unit and the light beams subjected to the retro-reflection of the retro-reflection unit return to the grating along the same optical path in the direction of the incident light. After being subjected to a second-time retro-reflection unit, the light beams return to the measurement unit along the same optical path. After being subjected to action of the measurement unit, the light beams enter the signal output unit and measurement signals are output from the signal output unit. The measurement system provided by the invention is less susceptible to environment during working and has a better repeated accuracy compared with an interferometer. At the same time, the measurement system can meet application requirements of a large vertical measurement range.

The invention discloses a tripod capable of being fast leveled. The tripod comprises a base, three supporting legs and a leveling fixed seat, each supporting leg comprises a sliding seat and a sliding rod, a locking knob is fixedly arranged on each sliding seat, the fixed supporting legs are connected with the base through the locking knobs, and supporting feet are arranged at the ends, away from the sliding seats, of the sliding rods. Precision adjusting mechanisms are arranged between the sliding seats and the sliding rods, and the length of the supporting legs can be precisely adjusted through the precision adjusting mechanisms. The leveling fixed seat is arranged on the base and comprises an equipment mounting seat, a linkage fixed plate and a plurality of leveling knobs, measuring equipment is arranged on the equipment mounting seat, the leveling knobs are arranged on the lower portion of the equipment mounting seat and used for precisely adjusting the flatness of the equipment mounting seat, and the linkage fixed plate is clamped on the leveling knobs. The tripod has three adjusting methods of rough adjusting, precise adjusting and fine adjusting, the tripod can be unfolded, leveled, dismounted and stored fast, the leveling precision of the tripod is high, the leveling error can be controlled within 20 degrees, the precision stability is high in the long-term work process, and the precision stability is slightly influenced by environment temperature changes.

The invention relates to a tunable narrow-linewidth fiber laser based on an interval tunable phase shift fiber gratings. The tunable narrow-linewidth fiber laser based on the interval tunable phase shift fiber gratings comprises a laser device (LD), a WDM coupler, an erbium-doped fiber loop, an optical isolator, a circulator, the fiber gratings, a phrase shift fiber grating tuner, an optical coupler, a wavelength meter, an input and control circuit and an output optical coupler, wherein the WDM coupler, an erbium-doped fiber, the optical isolator, the circulator, the phrase shift fiber grating tuner and the optical coupler form an loop cavity; the circulator, the fiber gratings and the phrase shift fiber grating tuner form an adjustable filter inside the cavity. Phase shift amount of the phrase shift fiber gratings is changed by changing the length of an air gap between the two fiber gratings so that tuning of output laser wavelength can be achieved. According to the tunable narrow-linewidth fiber laser based on the interval tunable phase shift fiber gratings, the tunable phase shift fiber gratings, the optical coupler, the wavelength meter, the input and control circuit and the output optical coupler form an input and feedback control loop, the needed laser wavelength is obtained through feedback control, and stability of the laser output wavelength is ensured.

The invention discloses a method for correction during SLAM (simultaneous localization and map building) of a mobile robot. The method comprises steps as follows: Step1: historical data are acquired and checked, and deviation factors of historical message records during SLAM are analyzed and arranged; Step 2: parameters are adjusted and modified, a fitness function is set, a search updating modelis built, and secondary sampling is performed; knowledge correction is verified, a fitness function of Q and R is defined according to the inconformity of close observation, and discreet values of Q and R are searched with an improved fractional order particle swarm algorithm, and correction of Qt and Rt is completed according to the discreet values; Step3: a new route is corrected, and updating of a particle cluster is completed through prediction, data association, posture updating, weight calculation and road sign updating; resampling is performed, the number of effective particles is calculated, and normalization resampling is performed. The problem of route deviation caused by ineffective data deviation factors because of unstable factors of a sensor and the outside is solved.

The invention provides a magnetic suspension gantry processing center. The magnetic suspension gantry processing center comprises a base, two upright posts oppositely arranged on the base at intervals, a cross beam arranged between the two upright posts, a first sliding seat arranged on the cross beam, capable of transversely and horizontally moving, a second sliding seat arranged on the base, capable of longitudinally and horizontally moving, a machine head mounting rack arranged on the first sliding seat, capable of moving in a liftable manner, a machine head mounted on the machine head mounting rack, an object carrying table rotatably arranged on the second sliding seat, a first DD motor which is arranged between the second sliding seat and the object carrying table and is used for driving the object carrying table to rotate, an X-axis moving mechanism arranged between the cross beam and the first sliding seat, a Y-axis moving mechanism arranged between the base and the second sliding seat, a Z-axis moving mechanism arranged between the first sliding seat and the machine head mounting rack, and a control device connected with the X-axis moving mechanism, the Y-axis moving mechanism, the Z-axis moving mechanism and the first DD motor. According to the magnetic suspension gantry processing center, multiple technologies can be achieved, the precision reliability is high, the automation degree is high, and the maintenance is convenient.

An outer diameter measuring instrument for big size shaft type parts adopts the measurement principle of circumference three-point contact measuring method, and mainly includes a base, flare angle arms, a grating scale and a sleeve, wherein the two flare angle arms are in taper interference fit with the base; the sleeve is vertically arranged on the base; the grating scale is vertically arranged in the sleeve; a retractable and movable sensor contact terminal is arranged at the front end of the grating scale; the sensor contact terminal penetrates the center of the base and arranged between the two flare angle arms; a top block is arranged at the upper end of the grating scale; and a pressure pad and an end cover are arranged at the upper end of the sleeve. The working principle of the invention is that the indirect measurement method, namely the circumference three-point contact measuring method is adopted to measure the outer diameter of the cylinder; and the two flare angle arm structures forming a fixed angle can directly present the diameter variation of a tested workpiece through the displacement of the contact terminal of the grating scale, thereby guaranteeing the measuring accuracy, and solving the problem of error amplification caused by polar angle variation at the same time.

The invention provides a bearing base processing method for completing processing by one-time clamping and positioning so as to guarantee the processing precision, decrease the labor intensity and improve the processing efficiency. In the bearing base processing method, a pair of bearing bases is positioned opposite to each other and fixed on a bridge plate that can rotate around the fourth shaft of a four-shaft processing center; firstly, the bearing bases are processed, then, the bridge plate is driven to rotate 90 degrees, and finally, the bearing bases are processed continuously.

The invention relates to a measurement device for volume deformation of foam concrete under a condition of steam curing, and aims at solving the problems that in the prior art, under the environment of steam curing, measurement for the volume deformation of the foam concrete in the early period is inaccurate and the continuous measurement for deformation of the foam concrete can not be achieved. The device includes a box cover, a box body, a heating water tank, a plurality of temperature sensors, automatic windshield wiper components, a computer, a connecting component, support bases, a temperature control box, two supports, two beams, multiple separation supports, multiple heating pipes, multiple reflection targets, a plurality of debugging modules and multiple laser displacement sensors, wherein the bottom of the box body is provided with the heating water tank and the temperature control box, the top of each debugging module is provided with a refraction target, the automatic windshield wiper components are arranged on the box cover, the laser displacement sensors are connected with the computer through circuits, and each temperature sensor is connected with the temperature control box. The measurement device for the volume deformation of the foam concrete under the condition of steam curing is applied to the field of concrete deformation measurement.

The invention provides a system and method for drawing a driving track on the basis of vehicle data. The system comprises a track drawing module, bus data monitoring equipment, an OBD interface and an intranet CAN bus; the bus data monitoring equipment is connected to the OBD interface and the intranet CAN bus of a vehicle and used for monitoring a vehicle bus and transmitting data to the track drawing module, and the track drawing module is used for analyzing the data and drawing the track in real time. According to the method, the method of drawing the driving track according to the driving data of the vehicle itself is adopted, the driving track can be recorded in real time without needing external information, and meanwhile a high-precision inertial navigation module is not needed, so that the measurement cost is reduced.

The invention discloses a real-time deducting background nonlinear correction method for detecting the concentration of oxygen in glass bottles by means of wavelength modulation spectroscopy. The real-time deducting background nonlinear correction method includes acquiring secondary harmonic data of the glass bottles with the oxygen concentration of 0% and to-be-detected glass bottles, carrying out data mean and filter processing on the secondary harmonic data, carrying out nonlinear correction and then extracting corresponding harmonic characteristic peak values P<0> and P; utilizing a half of the sum of each characteristic peak value P' of atmosphere and a characteristic peak value P'<21> of each glass bottle with the oxygen concentration of 21% when oxygen concentration inversion modelsare built as a threshold for detecting the availability of the bottles, further carrying out real-time deducting background and multiplication correction processing if the harmonic characteristic peak values P are smaller than the threshold, in other words, dividing the characteristic peak values P<0>' of the glass bottles with the oxygen concentration of 0% when the models are initially built bythe current characteristic peak values P<0> to obtain correction factors, multiplying (P-P<0>) by the correction factors to obtain actual characteristic peak values of corresponding to-be-detected samples and feeding the characteristic peak values of the to-be-detected samples into the concentration inversion models to predict the concentration of the oxygen in the glass bottles. The real-time deducting background nonlinear correction method has the technical advantages that background fluctuation can be suppressed, and the precision and the stability of prediction for the concentration of the oxygen in the glass bottles can be effectively improved.

The invention discloses a method for filtering car networking data. The method for filtering car networking data comprises the following steps: primarily processing traveling data; correcting and precisely filtering the traveling data after the traveling data are stored into a warehouse; and processing the data for different applications, recognizing abnormal working states of equipment, detectingfabricating data and filtering out the fabricating data. The obtained traveling data are filtered, the traveling data which are mistake obviously are removed, and the original travel is maintained asmuch as possible. The step of correcting and precisely filtering the traveling data after the traveling data are stored into the warehouse comprises: correcting abnormal data points; and removing mistaken data points. The traveling data of an equipment end are acquired and processed primarily, and the problem that mistaken traveling data are uploaded to a server to occupy storage space and resources is avoided. The traveling data are filtered and corrected, and the precision and stability of an algorithm are further improved. The accuracy and stability of follow-up applications such as driving behavior analyzing application and traveling analyzing and drawing application will be enhanced.

The invention discloses a tooth row positioning device. The device is characterized by comprising a chain positioning block, an adjusting screw, a chain, a connecting block, a tooth row body, a post-positioning swing rod, and a positioning roller, wherein the connecting block is connected with the chain; the chain positioning block is fixed on a fixing part; the positioning roller is a roller on a chain link of the connecting block; the two ends of the tooth row body are fixedly connected on the connecting block respectively; the post-positioning swinging rod is a symmetric part; and the adjusting screw is arranged on the chain positioning block. A working method comprises the following steps of: positioning the tooth row body at a processing position; rotating the post-positioning swinging rod counterclockwise; lifting the tooth row body and the connecting body; after finishing positioning, starting processing paper; after finishing processing, rotating the post-positioning swing rodclockwise; descending the tooth row body and the connecting block; and after separating completely, positioning the tooth row body to a next position. The device has the following advantages: solution of the problem of chain stretching of equipment after printing, improvement on the precision stability of the equipment after printing, simple structure, reduction of space occupation, reduction of maintenance installation cost and improvement on work efficiency.

The embodiments of the present invention disclose an unmanned aerial vehicle image positioning and attitude determination method and an unmanned aerial vehicle, and relates to the technical field of unmanned aerial vehicles. The unmanned aerial vehicle image positioning and attitude determination method comprises: acquiring camera internal reference, images and on-board POS data; carrying out distortion correction on the images according to the camera internal reference to obtain distortion-free images; extracting the feature points and the feature descriptions from the distortion-free images;carrying out constraint by using the on-board POS data to complete the rough matching of the features; carrying out relative orientation to obtain the essential matrix between the images; extractingthe feature points and the feature descriptions from the distortion-free images; carrying out rapid high-precision matching by using the essential matrix in the rough matching as epipolar constraint;calculating the correlation between the images; obtaining a subgraph through a regional growth method; and carrying out incremental reconstruction in the subgraph, and then carrying out global optimization reconstruction, and adding the camera internal reference during the global optimization reconstruction so as to finally obtain the precise position and the precise attitude of the unmanned aerial vehicle image. With the method and the unmanned aerial vehicle of the present invention, the accuracy of the unmanned aerial vehicle image positioning and attitude determination can be improved.

The invention discloses a paper pulp molding forming machine, comprising a machine body and a paper pulp slot lifting mechanism, a transfer die mechanism, a lower die moving mechanism, an upper die pressing down mechanism and a collecting mechanism which are arranged on the machine body; the paper pulp slot lifting mechanism is used for forming a paper pulp box; the transfer die mechanism is used for transferring the paper pulp box formed in the paper pulp slot lifting mechanism to the lower die moving mechanism; the lower die moving mechanism is used for sending the paper pulp box to the position of the upper die pressing down mechanism and is matched with the upper die pressing down mechanism to press and shape the paper pulp box; the upper die pressing down mechanism comprises an upper die assembly and a servo pressure cylinder for driving a lower die assembly to move up and down, and the servo pressure cylinder is of a mechanism drive structure. Mechanical drive is adopted, and the problem of pollution caused by hydraulic drive in the prior art is fundamentally solved; the precision and stability during work of the paper pulp molding forming machine are improved and the production cost is reduced while the production efficiency is improved.

The invention discloses a ball screw pair with automatic compensation of thermal deformation, and belongs to the field of advanced manufacturing. A ball screw body and aramid fibers are pasted together through adhesive. A through hole is drilled in the axial direction of a screw shaft of the ball screw body, the aramid fibers are pasted to the wall of the through hole through adhesive, and therefore the direction of the aramid fibers is kept consistent with the axial direction of the ball screw body. By the adoption of fiber materials with a minus thermal expansion coefficient, the ball screw pair and the screw shaft are both heated, then the ball screw pair automatically obstructs axial expansion of the screw shaft, can compensate for errors caused by thermal expansion of the screw shaft in a self-adaptation mode without a control device, and therefore the precision stability of the ball screw pair is improved. Although holing in the screw shaft will influence the bending rigidity and axial rigidity of the ball screw pair, the aramid fibers in the axial direction will improve the bending rigidity and axial rigidity of the ball screw pair due to the fact that the elasticity modulus of the aramid fibers is large, and the rigidity will not be affected.

The invention provides an intracavity enhanced dual-wavelength common-path phase microscopic imaging measurement system based on an F-P interferometer. The system is characterized by being composed ofa laser light source 1, an optical attenuation sheet 2, an optical fiber coupler (LFC) 3, a single-mode optical fiber 4, an optical fiber collimator (FCL) 5, a beam expander 6, an F-P interferometer7, a to-be-measured object 8, a microscope objective 9, a CCD detection camera 10 and a computer 11. The system can be used for digital holography and refractive index measurement of tiny objects, andcan be widely applied to the field of refractive index three-dimensional microscopic imaging of various tiny objects.

The invention discloses components and parts of a mechanical machine tool and a manufacturing method thereof. The manufacturing method mainly comprises the following steps: according to characteristic structures and the high rigidity of the components and parts of the mechanical machine tool, mounting and setting proper steel brackets, reinforcement net materials and other reinforcement structures into mold cavities of a molding mold; mounting required metal parts, wiring pipelines, tracks and other embedded components; and then pouring the mixed slurry of artificial stones into the molding mold for coagulation formation, and after demolding and subsequent manufacturing operations, obtaining the components and parts of the mechanical machine tool consisting of artificial stone bodies. The manufacturing process is simple and reduces the energy consumption; and simultaneously, characteristics of the artificial stones can be utilized to endow the components and parts of the mechanical machine tool with excellent mechanical performance, such as good vibration damping effect, low coefficient of heat conduction and the like.

The invention relates to a three-axis servo feed transmission structure of a machining center, which comprises a ball screw, a nut seat, a motor seat, a bearing seat, a lock nut, two groups of precision bearings supporting two ends of the ball screw, a coupling and a servo motor; an outer side seal and an inner side seal are respectively placed on two sides of each precision bearing, and a limit buffer collision block is placed on the ball screw which is near to the precision bearings; a gap is preserved in the position of an internal shoulder of a back-end lead screw of the ball screw; and the pre-stretched lock nut is placed at the tail end of the ball screw. The three-axis servo feed transmission structure has the benefits of improving the precision and the stability of servo transmission, having high universalization rate of parts, controlling the production cost, reducing the failure rate and facilitating the repair and the maintenance.

The invention relates to a novel wall type hanging hook, and aims at solving the problem that an adjusting plate is easily non-uniform in force bearing to cause reduction of stability and precision while reciprocating to adjusting the absorbing force of the existing sucker type hanging hook. The novel wall type hanging hook comprises a hanging hook, a sucker, a hanging book body and a screwing cover; a baffle is arranged at the upper end of the screwing cover; a pulling rod which is connected with the baffle is arranged on the central part of the sucker; a first elastic part is connected between the baffle and the hanging hook body. The novel wall type hanging hook further comprises a pressing ring and a second elastic part; two symmetrically-distributed cam surfaces are arranged on the end surface of the screwing cover; a check ring is fixed in the periphery of the screwing cover; an annular chute is formed in the check ring; a pressing ring is arranged in the annular chute; the second elastic part is distributed in the periphery of the hanging hook body; one end of the second elastic part is connected with the hanging hook body and while the other end of the second elastic part is connected with the pressing ring. According to the novel wall type hanging hook, the reciprocating adjusting structural design is adopted, so that the screwing cover can be kept in a balancing state all the time during rotating, and as a result, the stability and precision of adjusting can be improved; the novel wall type hanging hook has the advantages of being convenient and reliable to operate, high in stability, high in adjusting precision, and long in service life.

The invention relates to a scale error compensation strategy for a rotary type strapdown inertial navigation gyroscope. The scale error compensation strategy is characterized by including the steps of firstly, performing power-up initializing and coarse alignment on inertial navigation equipment; secondly, performing double-shaft rotation modulation fine alignment; thirdly, performing compensation calculation on gyroscope scale errors and performing compensation. The scale error compensation strategy has the advantages that the new gyroscope scale after compensation is calculated by analyzing the causes of azimuth angle oblique shifting and according to inertial navigation output azimuth angles, compensation calculation is performed in the gyroscope scale errors, the rotary type strapdown inertial navigation gyroscope scale factor errors can be compensated effectively, the gyroscope scale factor errors can be compensated forwardly and reversely, and inertial navigation data output precision and stability are increased.

The invention provides a bearing base processing method for completing processing by one-time clamping and positioning so as to guarantee the processing precision, decrease the labor intensity and improve the processing efficiency. In the bearing base processing method, a pair of bearing bases is positioned opposite to each other and fixed on a bridge plate that can rotate around the fourth shaftof a four-shaft processing center; firstly, the bearing bases are processed, then, the bridge plate is driven to rotate 90 degrees, and finally, the bearing bases are processed continuously.

The invention discloses a time lag fractional order-based ship motion adaptive sliding mode control method. The method comprises the following steps of S1, establishing a target virtual ship motion model, and setting a mathematical model according to the target virtual ship motion model; S2, solving a state space in the mathematical model in the step S1; S3, solving a state error according to an expected state of a system; S4, substituting a state error in the step S3, and constructing a sliding mode surface function; and S5, approaching uncertainty of the system by using the control input andthe state information at the latest moment, and constructing an adaptive control law to control the sliding mode. The method is advantaged in that by means of the self-adaptive sliding mode control algorithm, the ship can be automatically adjusted when being disturbed, and a stable state of the ship can be rapidly restored.

The invention discloses a method and a plate flipping milling machine for achieving five-axis gantry horizontal plate flipping milling. The milling machine comprises a gantry side wall, a working table, a flipping table, and a first driving unit and a second driving unit for driving the working table to perform position switch between the flipping table and the gantry side wall, wherein the firstdriving unit and the second driving unit are respectively arranged on the gantry side wall and the flipping table, a third driving unit for driving the flipping table to flip is arranged at the flipping table position, the working table is subjected to position switch between the flipping table and the gantry side wall through a sliding channel, and the gantry side wall and the flipping table arerespectively provided with a locking mechanism for locking the working table. According to the present invention, the horizontal processing is beneficial to efficient chip discharge so as to improve the processing efficiency, reduce the cutter wear, and greatly reduce the time for cleaning chips; and on the basis of the bridge type gantry, the automatic exchange of the working table is achieve, and the automation function of the machine is increased, or the fully automatic production line is formed through expanding so as to further improve the production efficiency.

The invention provides a permanent-magnet synchronous engraving and milling electric spindle adopting internal cooling for a shaft core, and belongs to a vertical engraving and milling electric spindle. The electric spindle comprises a rotatable main shaft core, a liquid flow distribution rotary shaft used for cooling the main shaft core, a rear bearing and a front bearing which are used for supporting the main shaft core, a water jacket shell body used for cooling a stator and the bearings, a front pipe joint used for air curtain protection, and a liquid backflow and reduced-pressure recoverybox used for the flowing of a cooling liquid. According to the scheme, a spindle installation structure with vertical layout is adopted, simultaneous temperature control cooling is carried out on thestator and a rotor of a motor, the same cooler or two coolers can be used for the stator and the rotor, and temperature management is carried out on heating parts of the spindle, so that accuracy management in the length direction of the spindle is realized, and high-precision machining is achieved. The electric spindle is an electric spindle with controllable thermal elongation and high accuracyand reliability, and has the advantages of being simple in structure, stable and reliable in working, and the like.