DE2236100A1 - CARBIDE DRILLING TOOL - Google Patents

Description

Description of the Patont application. Carbide drilling tool, drill in Experience has shown that solid carbide grinders are used for larger drillings because the hard metal briefly destroyed in the drill bits by the brittleness of the sintered material will.

In practice it is known to use hard metal for drilling into solid material to be used, for example in the form of a StuSen twist drill with high-speed steel material, where in the 2nd stage, also the larger diameter of the spiral, Hartir-etall platelets are soldered on.

This design can only be used to a limited extent in practice, since the instability of the Behrer spiral creates vibrations and oscillations that the Tungsten carbide cutting edges quickly become blunt and destroy relatively quickly.

The reduction of the feed to a minimum in order to reduce the vibrations experience has shown that it can be reduced in practice and in particular for continuous operation only very unsatisfactory Brgebaisse, because the hard metal cutting edges with low chip removal exhibited high wear and tear and relatively rapid dulling.

The application is known and with reasonably good results combined drilling and vision tool, i.e. twist drill with countersink, whereby the latter is made of hard metal or equipped with Hart @ etsll tipping. He serves preferably for drilling, then countersinking and surface of screw holes in one operation.

The invention of a hard metal drill described below gives now - as has been shown by long practical experiments - the possibility of using Nartmetall in solid material such as metal and steel of any strength and hardness, with the permissible high cutting speeds, to drill without - as with the previous ones known Versions, impermissible vibrations, the dart metal cutting edges shortened in service life or be destroyed quickly.

In the attached drawing, the longitudinal view is shown in Figs. I and II and in picture III and IV the front view of this hard metal drilling tool shown.

The cutting tool consists of the strong inner shaft part (1) with for example Norse or steep taper shank (2), on the al front part the drilling tool (i) - replaceable - is screwed on. The rear switching part (1) is expedient with the largest possible diameter (depending on the length of the same) formed around a high To achieve stability for the front drilling tool (3). Length and diameter of the shaft (2) are appropriately adapted to the working conditions.

The screw-on drilling tool consists of the drill shaft (3), which at the front end, for example, 2 Hertmet llstten (4) offset by 180 ° with an appropriate Cutting angle becitzt. Depending on the depth of the hole, the front part of the drill shaft can be chosen in full length. With consideration for the highest possible Gt @ biligät and Vibration-free will be chosen as short as possible.

Ent @ reeben @ the required or intended depth @@@@ i @ pre-position drill shank for chip evacuation straight or Spiral grooves (5) arranged distributed by 180 °, and only so long and deep to ensure good drainage, of the chips.

On the other hand, also to secure the coolant supply to the drill cutting edges.

The front drill shaft (3) is fitted in the center with a short one so-called pointed drill (6) flat material in Werketoff - good high speed steel - arranged. (Picture I and II.) Wablweise can mail this central drill in high-speed steel with run a round shaft (7), which then at the front end, be it in the form of a flat pointed drill or similar with 2 appropriate drill bits by 180 ° is provided offset.

These central drill cutting edges can, depending on the material and the absence of chips protrude 0.5 - 2 mm from the hard metal cutting edges (4) or at the same height can be arranged with dlesen.

With a retaining screw (8) in the shaft (3), the Central drill (6) or (7) fixed against shifting to the front.

On the other hand, the rear face of the central drill lies with ibrem Feed pressure against a length adjustment screw (9), with which, for example, when Nychsohleifen the cutting edge these can be readjusted to the intended position.

The diameter of the central drilling will vary on a case-by-case basis or for example selected so that the normal permissible cutting speed for high-speed steel cutting is not exceeded.

tool # is 1: 2/1: 3, so that the hard metal cutting edges Drill on the outside # with a medium to max.permissible cutting speed. the Cutting performance of this carbide drill compared to a twist drill of the same outer diameter can be 2 - 3 times. Apart from the longer service life that is achieved can, is the economic advantage of the subject of the invention for the machining Machining very remarkable in modern manufacturing.

Claims (2)

Patent Claims Tungsten carbide boring tool d a d u n g e k e n g e s t that 1) the drill tool shank (3) with one or more carbide cutting inserts (4) is equipped and in the center of this shaft (3) is a flat pointed bullet-shaped Drilling tool (6) with a flat shank or one with a round shank (7) is arranged is. 2) the drilling tool shaft is designed with appropriate flutes (5) 3) a support and Nachatell screw (f) is provided for the central drill is. L e r s e i t e