SU659347A1 - Gear-hobbing machine - Google Patents

Description

one

The invention relates to the field of machine tools.

A gear milling machine for cutting cylindrical, worm gears and bevel gears is known for a cylindrical screw cutter, equipped with a rolling chain including a differential and kinematically connected with a vertical feed chain of the milling cutter.

However, this machine does not allow to get the helix of the tooth of variable pitch on the cone, since the rolling chain ensures a constant 1) 1st turn of the workpiece table. On the proposed machine it is possible cutting conical wheels with a helical tooth.

For this purpose, a kinematic chain of uneven turning of the workpiece is introduced into the machine, made in the form of a conical pair, irradiated into a frenzy from the vertical feed chain and controlled by a guitar of replaceable wheels and a worm gear with a profile cam, which is connected with the differential rolling chains.

FIG. 1 shows the general kinematic diagram of the machine; in fig. 2 - chain of uneven turning of the workpiece (deployed).

The base 1 of the gear milling machine is equipped with guides 2, on which a table 3 is installed, carrying the workpiece of the cutting wheel 4.

The lead screw 5 serves to set the cutting depth, and the lead screw 6 to radially feed the workpiece. On a fixed caliper rack 7 fixed rotary body 8 of the milling support 9 with a variable pitch 10 milling cutter 10. The machine has a main motor 11 and an engine 12 accelerated moves of the table, milling support and diagonal feed.

The rolling chain consists of

worm gear 13 to rotate the table with the workpiece 4, fission guitars with interchangeable teeth 14, differential 15, bevel gears 16, 17, 18 of the cylindrical gear 19.

The kinematic chain of change of the cutter's cutter consists of a worm gear 20, a node of a change of a schag, made in the form of a guitar of replaceable wheels 21, a coupling 22 for switching on this chain of a worm gear

23 and the differential 24, which transmits the rotation to the threaded bushing of the assembled worm cutter.

The gear sectors are attached to the table body 3 on both sides, ensuring the rotation of the axis of the table from the vertical position to the horizontal and slightly more than 90 °. The rotation of the table was carried out: CTS relative to the axis of the screw, which rotates the table. On the axis of the screw, there is a taper pair, kinematically connected with interchangeable gear sets of division.

The formula for the ioduscount of replaceable dividers is

and with A-k

B d g

where A is nosto n. on the machine;

/ g - the number of entry of the hearth mill; Z is the number of bevel gear teeth cut.

The counting of replaceable gears of the guitar 21 is made according to the formula:

a with A (2- -} -5th b d

i-gp

gfrgde A - machine stand;

 / 2 - normal pitch in a large additional cone of the wheel being cut, mm;

ti is the normal pitch in the small additional cone of the wheel being cut, mm;

SB-vertical feed, mm / rev, table;

2fr - the number of teeth cutters; in - the width of the rim of the cut wheel, mm;

/ p - step grooves of the first tooth of the threaded sleeve of the cutter.

The chain of uneven turning of the workpiece includes a conical pair 25, a worm gear 26, a guitar of interchangeable gears 27, a non-profile cam 28, a slatted pair 29 and a differential 30. The chain is designed to get helical tooth bevel gears.

The magnitude of the uneven rotation of the workpiece is carried out by a replaceable set of this node depending on the change in the normal module. At the same time, the rate of change of the normal module is directly dependent on the magnitude of the vertical feed,

The principle of operation of the proposed hobbing machine is based on the current engagement of the tooth of the wheel being cut with a variable pitch rail, expressed by a variable pitch worm mill. The interaction of the chains is achieved by matching the rotation of the cutter and the workpiece with the rate of change of the cutter pitch at the time of the meeting of the cutting edge and the tooth of the wheel, depending on the vertical feed.

The main motor of rotation of the milling cutter 11 through the drive belt drive, interchangeable wheels, four pairs of bevel wheels 31, 16, 17 and 18 and cylindrical wheels 19 transmit the rotation to the spindle of the worm cutter 10. By turning the bevel wheels 16

through the differential 15, the cylindrical wheels 32, the interchangeable division wheels 14 and the cylindrical wheels 33 are transmitted to the rotation of the table shaft, which through the cylindrical wheels 34, the conical pair 35 and the worm gear 13 transfers the rotation to the table with the workpiece.

From the last wheel of a replaceable set of divisions, the rotation of the worm is transmitted.

a pair of 36, a cylindrical wheel. 37, which transmit rotation to the interchangeable feed wheels 38, then through the cylindrical wheels 39, 40, 41 and the worm gear 42, the screw 43 is set in motion,

the milling support 9 with the milling cutter 10 communicates vertical feed.

The cutter spindle transmits the cylindrical wheels 19, which, when the clutch 22 is on, rotate the screw

gear 20, interchangeable wheels 21, a worm gear 23, a differential 24, which rotates the threaded milling cutter, changing the size of the schrach of a worm cutter. Chain of uneven turning of the workpiece

gets the motion through a conic pair 25. The drive gear of this pair is mounted on the drive shaft of the main differential. A conical pair through a worm gear 26 provides rotation of the interchangeable gear set 27. The replaceable dial rotates the profile cam 28. The maximum angle of rotation of the cam (working portion) is 270 °. The remainder is used for turning and turning the cutter.

for the width of the cutting rim of the conical wheel. The cam moves the rack pair 29, through the pinion gear and the additional differential 30, a non-uniform change in the rotation of the main differential is introduced to ensure that the screw of the non-removable screw is obtained on the proposed machine.

The sequence of work of mechaizm.mov when forming a screw lii and a non-timed step of the proposed hobbing machine is as follows. When the table makes one rotation around the axis, the axis of the cutter together with the spindle assembly moves along the vertical guides by

5c. In this case, the chain of change of the pitch of the national mill will change its pitch by the value of Ar, i.e. the mill in the new position will have a normal module different from the previous one. Povy normal module

will be greater than the previous one if cutting is produced from a small additional cone, or less when cutting from a large additional cone. At the same time, the new chain will make a change in the additional rotation of the table, equal in size to each section, providing the theoretical size of the arc in any section along the perimeter of the dividing cone:

  ijtgS (mm)

where m is the theoretical arc along the perimeter of the dividing cone in this section, mm;

p is the angle of inclination of the axial tooth of the cut conical wheel. The speeds of change of the normal steps of the internal mill and the outer wheel blank, as well as the changes of other parameters associated with it, are carried out automatically by the adjusting chains of the machine and depend on the vertical feed. This is achieved by the fact that the weight of the movement is related to the basic movement, which is the rotation of the table.

Claims (1)

Invention Formula Gear hobbing machine for cutting cylindrical, worm and bevel gears of cylindrical worm gear a milling cutter, equipped with a rolling chain, including a differential and kinematically connected with a vertical feed chain of a milling cutter, characterized in that, for the purpose of cutting taper wheels with a helical tooth, a kinematic uneven turning circuit of the workpiece is inserted into the machine, which is rotated from a vertical chain feeding a bevel gear pair controlling a worm gear and a replaceable wheel guitar with a profile cam, which is connected to a differential through a rack pair and an additional differential enu rounding. Sources of information taken into account in the examination of Application No. 836696, cl. In 23P 21/16, 1963, according to which a positive decision was issued about issuing copyright certificate.