Typical high speed is linear feed orgnaization

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1. 1) of 　 of 　 of  of deputy drive of new-style ball guide screw is right nut of ball guide screw transforms 　 of measure  　 deputily (1) the stiffness that improves a system. Move high, the foundation that static stiffness is drive of feed of implementation high speed. To raise the feed speed of system of transmission of nut of ball guide screw and acceleration, must raise the screwy stiffness of guide screw and axial stiffness above all. Main measure has: Guide screw uses hollow structure to undertake beforehand drawing processing, contact bearing through choosing thrust actor, raise the stiffness propping up of guide screw. In addition, be designed through optimizing and use advanced workmanship, make the fitness of ball and raceway is in groove, raise osculatory stiffness effectively thereby. (2) raise nut of ball guide screw deputy athletic speed. On the foundation that assures enough stiffness, the lead that increases guide screw nut and whorl head number are to raise nut of ball guide screw the efficient way of speed of deputy sharp movement. Below certain circumstance, OK still deputy to ball guide screw carry out drive of double electric machinery, use guide screw of ball of drive of electric machinery of a servo namely deputy, the ball nut that another servo electric machinery props up by bearing with opposite way drive, make below the circumstance that increasing guide screw rotate speed, the feed rate that yields workbench rises one times. (3) the calorific amount that reduces a system. The high speed of guide screw is rotational, ball moves circularly in the high speed inside raceway, be sure to produce much quantity of heat. In addition, undertake to guide screw to raise stiffness beforehand drawing also is met aggravate is calorific. Accordingly, of system of deputy transmission of guide screw of high speed ball calorific will more deputy than groovy ball guide screw get greatly much. Solve system of deputy transmission of nut of guide screw of high speed ball one of efficient way of calorific problem connect cooling fluid interior of hollow guide screw undertake enforcing circular cooling namely, can assure the precision of secondary system of ball guide screw effectively so. (4) reduce moment of inertia, improvement character of service. Reduce ball diameter appropriately, ball bearing uses hollow structure or ball chain medium ball bearing is pressed one big one small interval arranges the moment of inertia when waiting to all can reduce high speed to move and improvement the fluent sex when ball rolls quickly. Material of pottery and porcelain (wait like Si3N4) have hardness small, stretch model measures tall, thickness caustic of small, wear-resisting, life grows coefficient of big, linear expansion wait for an advantage, make ball will reduce temperature rise significantly with the new material such as pottery and porcelain, reduce noise, improve the high speed performance of system of deputy transmission of ball guide screw effectively.  　 is additional, raise ball guide screw the installation precision of the stiffness propping up of two end and ball nut, to increasing the critical rotate speed of ball guide screw, assure the precision of feed system, the smooth stability that improves motion is having main effect. Nut of guide screw of 2) new-style ball 　 of  of deputy applicable circumstance because coefficient of friction of deputy drive of nut of ball guide screw is small, transmission efficiency is taller, production cost is inferior, stronger to environmental adaptability, more as a result of nut of ball guide screw deputy technology matures, accordingly, classics after transforming, there still is certain chair in high speed machine tool. It is main in applying to, small load, speed uprights at 10 ～ 40m/min, acceleration at 0.

5 ～ 1.

Limits of 0g, journey is not more than the circumstance of 6m, in be being applied to namely machine tool of numerical control of cheap high speed. 2. Feed of drive of linear electromotor of 1) of 　 of 　 of  of linear electromotor drive makes  　 high speed unitly unit of feed of linear electromotor drive is shown 1 times like the graph, it measures feedback by slideway of linear electromotor, workbench, scroll, nicety system and defend the part such as the system is formed. Graph 1 high speed is linear of unit of electromotor drive feed make 　 2) linear motor basically  　 linear electromotor is a kind of electric machinery that makes linear motion. Because there is intermediate main transfer machinery between linear electromotor and actuator, make transmission construction of system simple, increase decelerate rate at the same time fast, implementation is started quickly and can moving reversely. (Electromotor of A) basket asynchronous; (Electromotor of B) linear asynchronous pursues the evolution of 2 linear electromotor is shown like graph 2(a) place, if will basket model asynchronous electromotor along radial sliver, and electromotor circumferential exhibit linear, the linear asynchronous electromotor that has to show to graph 2(b) place. Among them stator and primary correspondence, rotor and sub correspondence. By the linear electromotor that graph 2(a) evolves and comes, its are primary with sub length it is equal. As a result of primary and sub between should do opposite exercise, accordingly, to assure primary with sub the coupling between keeps changeless, in applying actually, primary with sub length it is unequal. The basic configuration of linear electromotor is shown 3 times like the graph, if simple length is shorter, call short primary; Conversely, call short sub. Because short primary structure is simpler, cost is inferior, because this is in system of feed of machine tool of high speed numerical control,use this kind of structure normally. (A) weak point is primary; (B) weak point is sub graph the basic configuration of 3 linear electromotor by on be narrated, linear electromotor is by what rotate to electromotor evolves and come, accordingly, polyphase electric current should be connected in simple heterogeneous winding hind, can produce magnetic field of an air gap, the wave of magnetic flux density of this magnetic field is linear shift, call travelling wave magnetic field. The working principle of linear electromotor is shown 4 times like the graph. Apparent, the floating rate of travelling wave and rotate magnetic field is round inside stator apparently linear velocity is identical, call synchronous rate, size can indicate with next type: Among them, vs is synchronous speed; F is power source frequency; τ is polar distance. Graph the working principle graph of 4 linear electromotor is below the cut of travelling wave magnetic field, sub guide mediumly will produce inductive electromotive force and electricity, all guiding electric current and interaction of air gap magnetic field, generation is tangential electromagnetism force (one is drawn to guide only in the graph a) . If primary it is fixed immobile, so sub the direction that advances along travelling wave magnetic field makes linear motion. If the speed of sub shift uses V to express, turn the speed that the size of poor rate is this to make clear linear induction motor for sub and floating rate and power source frequency and electromotor polar distance become direct ratio, accordingly, change polar distance or power source frequency are changeable the speed of electromotor. The 　 of join means  of 3) linear electromotor and machine tool workbench pursues 5 for inductive asynchronous linear electromotor is sectional graph, what it uses is to move short the configuration with primary, sub fixed length. Those who take three-phase winding is primary 6 super-cooling have) of multichannel cooling oil duct inside board 3(however, with fixed bolt 5 install instead in workbench 4 on. Take bar sub 2 through dead plate 1 with fixed bolt 8 outfit are in the base of linear electromotor 7 on, secure again next go up in machine tool lathe bed. Graph 5 inductions asynchronous is linear electromotor is sectional the picture looks from the angle of workbench, the workbench of linear electromotor drive is the primary carrier of linear electromotor, chafe to reduce at the same time, assure to true sport directs and prevent to overturn pitching moment, on the plane below workbench normally installation has 4 slide block that are linked together with scroll slideway, workbench and move short primary if pursue,with the join of slide block 6 are shown. Graph 6 workbench and move short primary the basis of 　 of equitable distribution  with the unit feed of drive of linear electromotor of join 　 4) with slide block is linear the installation means of electromotor, the structural composition of feed unit can be divided level and perpendicular two kinds of means. The graph shows pattern of bureau of the plain cloth that it is water 7 times, its advantage is: The structure is simple, installation is safeguarded convenient, workbench height is lesser. Defect is: Primary with sub the electromagnetism attraction between and the way with gravitational workbench are same, if the stiffness of workbench is insufficient, will make primary with sub the clearance between is reduced, affect the regular job of linear electromotor thereby. Accordingly, the feed of horizontal layout means is unit a case that appropriate uses at be less than medium load. Means of layout of  　 level can divide drive of the electromotor that it is sheet again (see a picture 7 (A) ) with double electromotor drive (see a picture 7 (B) ) two kinds. (Drive of A) odd electromotor; (Drive of B) double electromotor pursues the layout of drive of odd electromotor of horizontal layout means of 7 linear electromotor the characteristic of means is: The structure is simple, workbench the span between two slideway is lesser, the installation of measurement unit and maintenance are convenient, suit the situation with requirement not big thrust. The characteristic of means of layout of drive of  　 double electromotor is: Synthesis pushs muscularity, the span between two slideway is bigger, workbench suffers electromagnetism attraction be out of shape bigger, taller to the stiffness requirement of workbench, installation is more difficult also, measure as more complex also as control, reason applies to special situation only. Means of  　 perpendicular layout all is double electromotor drive, if pursue,8 are shown. (Outside A) perpendicular installation; (Perpendicular installation pursues inside B) the 　 of 　 of  of other construction unit of the unit of feed of drive of linear electromotor of 5) of 　 of perpendicular layout means of 8 linear electromotor (1) slideway. Because the athletic rate of unit of linear electromotor feed is high, the slideway when the job will bear very big move load He Jingzai to carry on one's shoulder or back, get of many sided overturn pitching moment. Additional, the acceleration that the attrition of workbench and slideway also can affect feed unit and calorific wait. Because this must choose the slideway structure with high accuracy, tall stiffness and old carrying capacity, choose the material with little coefficient of friction at the same time. Graph 9 be 4 to wait for slideway of scroll of tall stiffness of contact of sectional circular arc high speed. The coefficient of friction of slideway of this kind of scroll is only 0.

02, and move, static friction coefficient differs very small, can avoid effectively to give out heat and crawl, to load carries on his shoulder or back and can eliminate backlash beforehand, its stiffness is tall, carrying capacity is large, service life is long, can maintain working precision more for a long time. Graph 9 4 to wait for 　 of slideway of scroll of tall stiffness of contact of sectional circular arc high speed (2) survey a system. Because the mover of linear electromotor is linked together with workbench directly, because this can make closed circuit system only. Choose feet of orgnaization nicety grating to regard workbench position as detecting element normally.  　 　 (3) medicinal powder shrinkage fitting buy. Because linear electromotor is versed in the meeting when making produces much quantity of heat, because this must be adopted,come loose hot measure. Of linear electromotor primary, sub when joining with workbench and slideway, there is dead plate unit among, such OK take away quantity of heat by the medium of the job in connecting dead plate.  　 　 (4) antimagnetic device. Because the magnetic field of linear electromotor opens type, very easy and adsorptive magnetic material affects treatment precision thereby, because this must take antimagnetic step. If use three-dimensional fold formula,sealed cover obstructs whole machine tool rise. The 　 of applicable circumstance  of drive of 6) linear electromotor can obtain high rate and freeboard as a result of linear electromotor drive fast (60 ～ 180m/min or taller) , tall acceleration (1.

0 ～ 10g) , long distance and high accuracy, because this is usable,mix at the high speed of machining center of high-grade high speed and other type exceed machine tool of high speed numerical control. CNC Milling