Method of workpiece surface figuration and machine tool motion are analysed

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One, method of workpiece surface figuration with respect to machining character, it is according to specific design the requirement chooses corresponding cutting to machine a method namely: The opposite motion of cutting tool and workpiece is passed on the machine tool, excise redundant metal from work semifinished product, made formation accords with the process of the surface of the appearance of the requirement, dimension. Accordingly, the formation that machining process is workpiece surface process. 1.

The makes mechanical part surface appearance of workpiece surface is Protean, but familiar face is combined and become by a few kinds mostly. Plane of these watch biscuit draw together, columnar face, taper seat, spherical, helicoid, torus and figuration curved surface, pursue as follows 1. Graph these surfaces can regard type of 1 familiar face as to move along lead and be formed by a generatrix. Graph the 2 figuration processes that showed spare parts face. Bus and lead a general designation are produce a line. Graph the figuration process Nextpage2 of surface of 2 spare partses.

In the figuration method machining of common workpiece surface, workpiece appearance achieves jointly by the appearance of the opposite motion between workpiece and cutting tool and blade of cutting tool cutting. Same appearance, of cutting blade different, the opposite exercise between workpiece and cutting tool is not same also, this is the basis that forms all sorts of treatment methods. Have orbit law, figuration way, exhibit law, tangent law to wait, see figure above 3. Graph method of 3 common figuration 1) orbit law: Those who point to is cutting tool cutting point contact is between blade and workpiece surface, pass the opposite motion between cutting tool and workpiece, will realize exterior figuration by the athletic contrail of cutting tool point of a knife. 2) figuration law: It is to point to to line contact is between blade of cutting tool cutting and workpiece surface, the appearance of cutting blade produces a line with a when form workpiece surface identical, another produces a line to come true by the opposite motion of cutting tool and workpiece. 3) extend a law (Fan Chengfa) : It is to show to all sorts of tooth form the surface undertakes adding man-hour, the cutting of cutting tool is line contact between blade and workpiece surface, the intercrop of cutting tool and workpiece exhibits movement (or call clench the teeth motion) , the generatrix of tooth form surface is cutting blade of each instantaneous position the line that include sth resembling a net. 4) tangent law: Use the method that the edge rotates to do orbit to move to undertake machining to workpiece by the side of cutting tool. 2, the motion of machine tool of analysis of machine tool motion: Exterior figuration moves and assist movement. 1.

Exterior figuration moves: Form the motion that produces a line. · differs by compositive circumstance, can divide for: Simple figuration motion and compound figuration move. 1) simple figuration moves: If an independent figuration moves, form by alone whirligig or sharp movement, criterion this figuration motion calls simple figuration campaign. 2) compound figuration moves: If an independent figuration moves, be by two or two above whirligig or sharp movement, according to some kind of affirmatory motion the relation is combined and become, say this figuration moves for compound figuration. For example, when face of the cylinder outside turning of lathe tool of the circle outside using (see figure below A) , the sharp movement A1 of the whirligig B1 of workpiece and cutting tool is motion of two simple figuration. For example, when turning whorl (see figure above B) , form the opposite campaign between the cutting tool that corkscrewed yarn place requires and workpiece. Decompose its those who be workpiece to wait normally fast of whirligig B11 and cutting tool etc fast linear and mobile A12. B11 and A12 cannot each other are independent, the campaign that must keep strict between them concerns, namely workpiece when every turn, cutting tool moves with respect to even ground lead of a corkscrewed yarn. Compound motion tags suffix meaning of the symbol to be: The serial number that word of the first digit shows to figuration moves (the first, the 2nd, ... figuration motion) ; Word of the 2nd digit expresses to form same the serial number of the independent movement of a compound motion. · differs by action circumstance, can divide for: Advocate motion and feed move. 1) advocate motion: It is the opposite motion between cutting tool and workpiece. It makes of cutting tool before knife face can approach work, on excision workpiece by cut, made change is cut bits, complete the treatment that cut bits thereby. Popularly, advocate athletic rate is top, consume power the biggest, have only normally advocate motion. For example, when turning is machined, the circumgyrate motion of workpiece is advocate motion. Nextpage2) feed moves: It is to cooperate advocate athletic implementation is ordinal the add and opposite motion between the cutting tool that excises redundant metal layer continuously and workpiece. Feed motion and advocate the treatment that motion cooperates to be able to complete wants exterior geometry form, according to the need of figuration of workpiece face figure, feed motion can be many, also can be; Can be successive, also can the pace is entered. 2.

Assist movement: Realize all sorts of auxiliary movements of the machine tool, create a condition for exterior figuration. Cut motion, cut a motion, adjust motion, dividing movement with etc all sorts of idle stroke move. 3, all sorts of movement that the athletic connection of the machine tool wants to realize treatment process place to need, the machine tool is indispensible have the following main component: 1) the part that final implementation wants to move on actuator machine tool, wait like main shaft, tool carrier, workbench, they drive workpiece or cutting tool rotates or move. 2) source of the power on dynamical source machine tool, kind use communication asynchronous electromotor, pace to enter electromotor, dc servo electromotor, communication servo electromotor to wait. They provide power for the motion of machine tool actuator, in order to overcome cutting obstruction and attrition resistance. The machine tool can move a few times common source of a power, OK also every motion uses source of a power alone, former be like general accuracy machine tool, latter exactly the amount charges a machine tool. 3) gearing transfers the motion of dynamical source and power to actuator, or pass motion by an actuator additional, actuator, in order to maintain the exact relationship between 2 motion. Transmission system still can alternate athletic direction, speed reachs athletic category, if turn into whirligig,move point-blank. By dynamical source, gearing, carry out or carry out, gearing, carry out a transmission connection that make, call transmission catenary. The property that presses transmission catenary is different can divide for: Catenary of drive of the connection outside ① connects the transmission chain between dynamical source and actuator. It makes carry out a rate with be obtained fixed and athletic way, the change that its drive compares, affect productivity or exterior surface roughness only, do not affect the form that processes the surface and precision. Accordingly, there can be the drive such as tendency drive in transmission chain is being connected outside more deputy than inaccurate drive. If common lathe is in,the transmission catenary between electric machinery and main shaft is outside connection drive catenary. Catenary of drive of the connection inside ② connects the transmission chain that moves between an actuator and another actuator. It is deciding to machine exterior appearance and precision, have firm demand to the opposite motion between actuator. Accordingly, the drive that transmission chain connects inside is compared must accurate, not due the drive that tendency drive or instantaneous drive compare change deputy (be like belt-conveyor and catenary drive) . When turning whorl, the transmission catenary that makes sure the rigorous campaign between main shaft and tool carrier concerns is inside connection drive catenary. Two kinds of main transfer machinery include normally in transmission catenary: One kind is: Compare main transfer machinery surely (transmission comparing and transmission way are changeless) , if decide worm wheel of more deputy than gear, worm nut of deputy, guide screw deputy wait, call compare main transfer machinery surely; Another kind is: Displacement orgnaization (can be compared according to machining requirement commutation drive and transmission way) , if hang reversing mechanism of orgnaization of round of gearshift orgnaization, slippage gear gearshift, clutch,wait. Transmission principle pursues: To facilitate the drive that studies a machine tool is contacted, a few more commonly used compendious symbol represents transmission principle and transmission line, this is transmission principle graph. When turning whorl, center lathe has catenary of two main drive. One is outside connection drive catenary, namely from electromotor, L, 2, μ V, 3, 4, main shaft, say to give priority to athletic drive catenary, it passes the motivation of electromotor and motion to main shaft. V of the μ in transmission catenary gives priority to the displacement orgnaization of axial gearshift and inverting. Another by main shaft, 4, 5, μ F, 6, 7, guide screw one cutting tool, get the compound figuration between cutting tool and workpiece moves -- helix moves, this is inside connection drive catenary. Adjust μ F to be able to get different whorl lead. The transmission system of the machine tool analyses what the machine tool moves to deliver to facilitate understanding is mixed, connection case, often adopt transmission system plan. It is the transmission sketch map that expresses to realize a machine tool to move entirely. The specific main transfer machinery in every drive catenary uses graph lieutenant general to provide a sign simply (see national level GB4460 - cartography of 84 machine city, symbol of orgnaization kinematic diagram) express, indicate power of diameter of lead of the tine number of gear and worm wheel, worm head number, guide screw, belt annulus, electromotor and rotate speed. The main transfer machinery of transmission catenary, be delivered according to motion or connection order is ordinal arrange, be in in order to develop graphical type stroke can reflect main part in the outline of machine tool appearance of mutual position. CNC Milling CNC Machining