CS198340B1 - External thread turning attachment e.g. knuckle thread,by non-forming tool - Google Patents

Description

The invention relates to an additional device which makes it possible to machine an external, for example round, thread on a lathe by means of a non-face cutting knife.

The thread, in particular the round thread, has so far been machined with form cutters on universal lathes. This solution for the production of round threads is not productive and brings a number of drawbacks, such as high time consumption in the preparation of the machining itself, the necessity of using expensive shaped blades, the impossibility of using carbide cutting blades and last but not least the high noise generated especially during long thread machining. rods, for example drilling etc.

These additional disadvantages are eliminated by an additional device according to the invention, in that it consists of a nut connected to the gear, such as a gear for transmitting the lathe speed by means of a gripper, mounted together with the gear and the workpiece clamped therein. mounted on a through bolt, at one end of which an eccentric for operating the knife holder is fixed.

The advantage of the additional device according to the invention (6SU) is particularly high labor productivity and the associated labor saving, as well as high precision of the machined thread when using standard non-face blades with sintered carbides. The device according to the invention also significantly reduces noise, especially during thread turning. on shorter workpieces.

An exemplary embodiment of an additional device according to the invention is shown in the accompanying drawing, in which Fig. 1 shows schematically a plan view with partial axial sections and Fig. 2 shows a side view with partial section of the support and the bed.

The attachment operates in such a way that after clamping the workpiece 2 in the chuck 1 and supporting it with the driving tip 7, the support 3 is moved to the beginning of the workpiece 2. After starting the lathe, its revolutions are transmitted through the workpiece 2, the driving tip 7 and the gear 6 on the nut 5, When rotating the screw 4, the knife holder 9 supported by the support 13 performs an oscillating movement. The magnitude of this movement is determined by moving the eccentric axis 12 relative to the axis 11 of the screw 4, which is equal to one half of the depth of the thread to be machined. The pitch of the bolt 4 is selected such that its suitable combination with the transmission between the gear wheel 6 and the nut 5 achieves a difference of one revolution to the value of the slide 3 by one pitch of the machined thread. The difference - with a suitable transmission, as mentioned above - is achieved after switching on the shift 3 of the lathe, when the bolt 4 is pulled out of the nut 5 and thus the mentioned difference of one turn to the right or left between

Claims (1)

SUBJECT An auxiliary device for turning an external thread, for example a round, non-face cutting knife, provided with a thread whose pitch equals the thread pitch of the machined thread and by displacing the screw axis relative to the eccentric axis by half of the thread depth, characterized by a nut (5) by the gear, the workpiece 2 and the eccentric 8, which makes it possible to turn the right and left threads. The device according to the invention can advantageously be used in particular for turning round threads, for example for drill bars, preferably for a minimum of noise, especially for shorter bars, etc. A toothed wheel (6), for example, for transmitting a lathe speed by means of a gripping tip (7) mounted together with a gear and a workpiece (2) clamped therein, the nut (5) being mounted on a through bolt (4). an eccentric (8) for operating the knife holder (9) is fixed at one end.