Thread machining method is summed up

Huai Yate and W.

Huai Yate's brother won the patent that cuts the bolt that make wood with special unit. 1778, english J.

Ramsden ever made use the whorl cutting device of worm wheel deputy drive, can machine the long whorl with a very tall precision. 1797, benefit of English Mo Ci, h.

On the lathe that improves by him, use mother guide screw and the metallic thread that exchange gear turning to give different pitch, established the basic method of turning whorl. 19 centuries 20 time, mocili makes a whorl of the first batch of treatment use tap and front tooth. At the beginning of 20 centuries, the development of auto industry promoted the development of the standardization of whorl and method of all sorts of nicety, efficient thread machining further, all sorts of stretch screw die head and automatic contractive tap automatically to be invented in succession, whorl milling begins to apply. At the beginning of 30 time, appeared whorl grinding. Whorl boils although there is patent in 19 centuries initial stage,press a technology, but create difficulty because of the mould, progress is very slow, till period of Second World War (1942~1945) , the development of the need that produces as a result of ammunition and whorl grinding technology solved the precision problem that the mould creates, just obtain rapid development. Methodological overview points to thread machining of 1 whorl cutting to use figuration cutting tool or grind a method that machines whorl on workpiece commonly, basically have turning, milling, tap, set silk, grinding, abrade wait with tornado cutting. When turning, milling and grinding whorl, workpiece every turn, the transmission catenary of the machine tool assures lathe tool, milling cutter or axial of workpiece of emery wheel edge is accurate and even ground moves a lead. Be in tap or when covering silk, cutting tool (tap or front tooth) make opposite whirligig with workpiece, guiding cutting tool by the whorl groove that forms first (or workpiece) make axial shift. On lathe turning whorl can use figuration lathe tool or whorl combs knife (see thread machining tool) . With whorl of turning of figuration lathe tool, because cutting tool structure is simple, it is odd a commonly used method with workpiece of pre production whorl; Comb with whorl knife turning whorl, manufacturing efficiency is tall, but cutting tool structure is complex, only comfortable the short whorl workpiece at fine tooth of the turning in production of medium, big batch. The pitch precision of whorl of echelon of common lathe turning can reach 8~9 level only commonly (JB2886-81, similarly hereinafter) ; Whorl is machined on the thread cutting lathe of specialization, productivity or precision can rise significantly. 2 whorl milling uses dish of form milling cutter on whorl milling machine or comb form milling cutter undertakes milling. Dish the whorl outside the echelon that form milling cutter basically uses on the workpiece such as milling silk lever, worm. Comb form milling cutter is used within milling, because be,common thread is mixed awl whorl, the length of section of milling cutter milling, its job is more than much blade to be machined again the length of whorl, reason workpiece needs to rotate only 1.

25~1.

5 turn to be able to be machined finish, productivity is very tall. The pitch precision of whorl milling can amount to 8~9 class commonly, exterior surface roughness is R5~0.

63 micron. This kind of method applies to the rough machining before the whorl job that produces general precision group by group or grinding. 3 whorl grinding basically is used at the accurate whorl of hard work of temper by dipping in water is being machined on whorl grinder. Whorl grinding presses emery wheel sectional appearance differs minute of single-track emery wheel and grinding of multi-line emery wheel two kinds. The pitch precision that grinding of single-track emery wheel can achieve is 5~6 class, exterior surface roughness is R1.

25~0.

08 micron, emery wheel nap is more convenient. This kind of method is comfortable the whorl workpiece at gauge of grinding nicety guide screw, whorl, worm, small lot and shovel grind accurate hob. Even if grind,grinding of multi-line emery wheel is divided again law and cut grind a way two kinds. Even if grind the emery wheel width of the law to be less than,be ground whorl length, emery wheel is fore-and-aft move or count second journey to be able to turn over whorl to grind final measure. Cut be more than length of the whorl that be ground into the emery wheel width that grinds a way, emery wheel radial cuts workpiece surface, workpiece turns about 1.

25 it is good to turn to be able to be ground, productivity is taller, but precision is a bit low, emery wheel nap is more complex. Cut grind a way comfortable wear lot at the shovel bigger tap and grinding are certain the whorl that close solid uses. 4 whorl are abrade with cast-iron wait for weaker data to make nut model or screw whorl grinds, to the whorl that already machined on workpiece the place of existence pitch error undertakes gyralling reversely abrade, in order to raise pitch precision. Temper by dipping in water is hard inside whorl also eliminates change with abrade method normally, raise precision. 5 tap and the tap that cover silk is it is certain to use twist the whorl inside the treatment in be apart from the bottom outlet that comes back tap to go up to be gotten beforehand into workpiece. Covering silk is to use screw die to expect in the club (or the canal expects) the whorl outside be being cut on workpiece. Tap or the treatment precision that cover silk depend on the precision of tap or front tooth. Inside treatment, outside although the method of whorl is very much, of Dan Xiaozhi diameter inside whorl can rely on tap to machine only. Tap and cover an usable handiwork to operate, usable also lathe, drilling machine, tapper and the machine that cover silk. 6 whorl boil pressure roll tool set to provide with figuration make workpiece produces plasticity to be out of shape in order to obtain the treatment method of whorl. Whorl boils pressure rolling filar machine commonly. Rub silk machine or in add outfit is automatic an automatic lathe that adds up to whorl to roll pressure head is aspirant row, apply to large quantities of quantities to produce standard fastener and other whorl connection outside whorl. Roll the external diameter that presses whorl not to exceed 25 millimeter commonly, length is not more than 100 millimeter, whorl precision can amount to 2 class (GB197-63) , the diameter of all blank roughly with be machined of whorl in diameter is equal. Boil pressure cannot machine commonly inside whorl, but pledge to material more flexible work can use tap of the extruding that do not have groove cold crowded inside whorl (the biggest diameter can amount to 30 millimeter to control) , working principle and tap are similar. Cold crowded inside the place when whorl needs to twist be apart from compare tap about 1 times bigger, treatment precision and exterior quality compare tap slightly tall. Whorl rolls the good point that approach is: Exterior surface roughness is less than turning, milling and grinding; Roll the whorl after pressing because the surface is cold make sclerosis and can raise intensity and hardness; Overall material utilization factor is high; Productivity machines twice growth than cutting, and implement automation easily; Roll tool set to have life very long. But roll the hardness that presses material of whorl requirement workpiece not to exceed HRC40; Taller to requirement of precision of semifinished product dimension; The precision that provides to rolling tool set and hardness demand are high also, production mould is more difficult; Unwell the whorl that presses tooth form asymmetry at boiling. Differ by what roll tool set to provide, whorl boils pressure can divide rub silk and roll silk two kinds. The rub that rub silk takes whorl tooth look two pieces filar board staggers 1/2 pitch is decorated relatively, static board fixed do not move, move board make parallel the move back and forth of Yu Jing board moves point-blank. Send when workpiece two board between when, move board ongoing rub approachs work, make its express dough modeling to the gender is out of shape and become whorl. Roll silk to radial boils silk, tangential boil silk and roll pressure head to roll silk 3 kinds. Radial rolls silk: 2 (or 3) those who take whorl tooth look roll filar annulus installation to be on the axis of mutual parallel, workpiece is put on two rounds of bearing between, two rounds with to etc fast rotate. Among them round still make radial feed motion. Workpiece is rolling filar annulus to drive next whirl, the surface suffers radial extruding to form whorl. Not tall to certain precision requirement guide screw, also can use similar method to boil press figuration. Tangential roll silk: Say planetary type rolls silk again, roll those who press a tool to rotate by 1 in the center of roll filar annulus and 3 fixed arc filar board composition. When rolling silk, workpiece can send into continuously, reason productivity rolls silk than rub silk and radial tall. Roll thrum to roll silk: Undertake on automatic lathe, use at machining the short whorl on workpiece commonly. Roll pressure head to have 3~4 all cloth at the week outside workpiece roll filar annulus. When rolling silk, workpiece rotates, roll feed of pressure head axial, roll workpiece extrude whorl. CNC Milling CNC Machining