TAP Russian patent published in 1997 - IPC

FIELD: mechanical engineering. SUBSTANCE: tap 1 is additionally provided with a feeding portion. Tap 1 has axial opening 3 with thread 4. The pitch and direction of thread 4 are the same as these of a thread to be threaded. The feeding portion is made up as screw 8 for receiving in axial threaded opening 3 of tap 1. The screw can be locked with respect to part 11 to be machined. The thread in axial opening 3 of the tap may provided from both sides. The feeding portion may be made up as screw 13 rigidly secured to tap 1 and arranged to the right or to the left of the cutting portion of tap 1. EFFECT: improved design. 5 cl, 7 dwg