SU975270A1

SU975270A1 - Tap

Info

Publication number: SU975270A1
Application number: SU803227332A
Authority: SU
Inventors: Анатолий Дмитриевич Максимов
Original assignee: Московский автомеханический институт
Priority date: 1980-12-30
Filing date: 1980-12-30
Publication date: 1982-11-23

Description

(54) МЕТЧИК(54) METER

1one

Изобретение относитс к области обработки металлов резанием, в частности к метчикам, и может быть использовано при нарезании точных резьб.The invention relates to the field of metal cutting, in particular to taps, and can be used when cutting precise threads.

Известен метчик дл нарезани точных резьб, состо щий из режущей части, на каждом зубе заборного конуса которой режуща кромка смещена к задней поверхности пера с образованием ступеньки на его передней поверхности за счет занижени наружного диаметра метчика, и хвостовика 1.A known tap for cutting exact threads, consisting of a cutting part, on each tooth of the intake cone of which the cutting edge is displaced to the back surface of the pen with the formation of a step on its front surface due to an underestimation of the outer diameter of the tap, and the shank 1.

Недостатками данного метчика вл етс то, что при .вступлении в работу резьбовой части метчика возникает неуравновещенна радиальна составл юща силы резани , в результате чего происходит разбивание отверсти и смещение оси инструмента относительно оси метчика, и тем самым снижение точности нарезаемой резьбы.The disadvantages of this tap are that when the threaded part of the tap enters into operation, an unbalanced radial component of the cutting force occurs, which results in breaking the hole and displacing the tool axis relative to the axis of the tap, and thereby reducing the accuracy of the cut thread.

Целью изобретени вл етс повышение точности нарезани резьбы.The aim of the invention is to improve the accuracy of threading.

Поставленна цель достигаетс тем, что в метчике дл нарезани точных резьб, состо щем из режущей направл ющей части, рабочей резьбовой части, на каждом зубе заборного конуса которой режуща кромкаThe goal is achieved by the fact that in the tap for cutting exact threads, consisting of a cutting guide, a working threaded part, on each tooth of the intake cone which has a cutting edge

смещена к задней поверхности пера с образованием ступеньки на его передней поверхности за счет занижени наружного диаметра метчика, и хвостовика, передн поверхность перьев рабочей резьбовой части выполнена с дополнительной ступенькой по всей их длине, причем диаметр этой ступеньки равен диаметру направл ющей части метчика. При этом остра кромка дополнительной ступеньки притуплена по всейshifted to the back surface of the pen with the formation of a step on its front surface due to an underestimation of the outer diameter of the tap and the shank, the front surface of the feathers of the working threaded part is made with an additional step along their entire length, and the diameter of this step is equal to the diameter of the guide part of the tap. At the same time, the edge of the additional step is sharply blunt all over.

Q длине пера.Q pen length.

На фиг. 1 изображен метчик, общий вид; на фиг. 2 - вырез пера и направл ющей части метчика; на фиг. 3 - разрез А-А на фиг. 1; на фиг. 4 - разрез Б-Б на фиг. 1.FIG. 1 shows the tap, general view; in fig. 2 - cutout of the pen and the guide part of the tap; in fig. 3 shows section A-A in FIG. one; in fig. 4 shows a section BB in FIG. one.

15 Метчик состоит из режущей направл ющей части 1, рабочей резьбовой части 2 и хвостовика 3. Передн поверхность 4 перьев рабочей резьбовой части 2 метчика выполнена со ступенькой 5, остра кромка 6 которой притуплена. Диаметр ступеньки Дс15 The tap consists of the cutting guide part 1, the working threaded part 2 and the shank 3. The front surface 4 of the feathers of the working threaded part 2 of the tap is made with step 5, the sharp edge 6 of which is blunted. The diameter of the steps DS

° равен диаметру Д режущей направл ющей части метчика.° is equal to the diameter D of the cutting guide of the tap.

Claims

When the tap is in operation, the cutting part 1 calibrates the hole for the thread. When the working part of the tap enters the 01 hole, the step 5 on the front surface of its 4 feathers, being a continuation of the cutting guide part 1 of the tap, since their diameters are equal (Ds Dn), provides him with exact direction to the calibrated hole. At the same time, the sharp edge 6 of the step 5 is blunt, which eliminates the influence of the unbalanced radial component of the cutting force arising at the time of entry into the hole of the teeth of the tap due to the fact that the steps 5 act as a smooth gauge. If necessary, the diameter of the pits of the teeth of the tap can be made smaller than the diameter of the steps. The proposed design of the tap improves the accuracy of the cut threads. Claim 1. A tap for cutting exact threads, consisting of a cutting guide bit, a working threaded part, on each tooth of the intake cone of which the cutting edge is offset to the back surface of the pen with the formation of a step on its front surface due to an understated outer diameter of the tap , and the shank, which compares with the fact that, in order to increase the accuracy of threading, the front surface of the feathers of the working threaded part is made with an additional step along their entire length, and the diameter of this step is equal to the diameter of the guide part of the tap.

2. Tap according to claim 1, characterized in that the sharp edge of the additional step is blunted along the entire length of the pen. Sources of information taken into account during the examination 1. USSR Author's Certificate No. 753568, cl. In 23 G 5/06, 1978.