DE2060051A1 - Drill driver - Google Patents

Description

"Bohr drreib s ob.raub"

The invention relates to a non-cutting or cutting machine '' Drill screw for fastening objects on sheet metal that is self-drilling and threading at the same time is formative.

123 are self-drilling and self-threading screws known that are easy to manufacture, can be used for hard and soft materials and without specially trained Special one-way screwing tools are operable. The drill bit this known Bohraehraüben white a straight line I cutting edge on which an increased contact pressure required during the drilling process. This increased contact pressure adversely affects production output and quality when making solvable Connections by reducing the drilling performance by quickly tiring the manual Processing of drilling screws and increased wear where the drill bit enters. Furthermore, the surface quality is reduced by increased contact pressure, dio dimensional accuracy of the bore and the Application ^ limited. In addition, through high pressing forces die 'life of the insertion tools adversely affected.

The purpose of the invention is to make a self-drilling endo "to create screw through which the technological Processing ratio improves that Quality of the detachable screw connections increased and labor productivity in processing the Screws increased.

The invention is based on the object of determining the cutting edge geometry of the drill driver screw to be developed the drill bit 3 as well as the son's cross-section B-surface to design constructively that one of the quality processing of Bohrschraubon corresponding machining performance is achieved *

109827/0935 _a .

BATH ORIGINAL

According to the invention, the object is achieved in that the drill tip of the drill driver screw has flattened areas which run as a broken surface towards the screw tip probe. From the naxiinal diameter of the drill point cuia first flattened areas extend which, with the normal to the screw aohae, enclose an angle that is approximately double; α ο is large as 7 / inkel by the aforementioned flattened portions with schnoidondeniind to ichraubonapitzonöndo verlaufendenAbflachungQimit the normal sur screw axis m form. The ones that run as a broken surface

Flattened areas result in a polygonal cutting edge. The outlet of the preferably spiral flute takes place under an increasing to the plane of symmetry 7angle. Between the laughs of Dohrspitsa and the plane of symmetry results in a free angle, the is designed as an obtuse angle.

The 3chneidq_uer cutting surface is contoured by overlapping Clamping, flattening and limiting bong fluting delimited, the distance between the axis of symmetry of the screw and the cutting edges being greater is than the distance zv / isohen the symmetry axis of the screw and the intersection of the flutes with the limiting

The technical-economic effects of the polygonal design of the drill bit consist in a reduced Contact pressure during the drilling process as well as a constant one Drilling performance and an improved quality of the screw connection, in particular with regard to surface quality and Dimensional accuracy of the bore, also in an increased service life of the drill bit of the screw and the lülndrohwerkzeugos. Due to the inventive constructive design Cutting geometry, the machining conditions are improved, which saves time and money will.

"> 109827/0935

BATH

The invention is intended below on the basis of an exemplary embodiment are explained in more detail. In the accompanying drawing show:

1: the front view of the screw;

Pig, 2: the side view of the screw in FIG . 1;

I? ig · 3: a section along the line A-A

in Pig. 1 ;

The screw shown in Fig. 1 consists of a known head 1 with Kreusachlits 2, which is followed by a cylindrical screw shank J with thread 4. The thread 4 is followed by a threaded shaft 5, which ends in a bolir tip 6 and which, initially cylindrical, runs conically outward up to a maximum diameter of the same. The drill bit 6 consists of pre-cutter 7 and! • Jaoliachneider 8 and vdrd initially formed by two opposite flats 9, which extend at an angle ß ^ to the normal of the screw axis from the maximum on-diameter of the drill tip 6 and cutting edges 10 on the trimmer 8 generate. Opposite flats 12 extend at the end of the screw tip 11, which rise at an angle A * which is approximately half the size of the angle and which the aforementioned flats 9 intersect · The flats 12 result in cutting edges 13 on the precutter 7 »The broken surface Flattened areas 9, 12 thus result in a polygonal cutting edge 10, 13. From the cutting edges 10, 13 there are spiral-shaped opane grooves 14 which are used for good chip evacuation. In order to achieve an optimal cutting transverse cut surface 15, the same is cut through; 3 opposing boundary surfaces 16, 17 between the spiral-shaped. Flute 14 and the flats mentioned above

109827/0935 BAD

9 or * 12 delimited such that the spacing λ of the intersection between dor spiral ^ pannut 14 and the Begrenzimgsflache 17 (Fiü x 3) is at 3ymmetrieaclise the 3oliraube! Your Iind than the distance a ^ from the intersection between the 3piralfürmißen flute 14 of the Flattening 12 on the axis of symmetry of the screw. The chip formation is supported by a pri angle q (~ , which results between the flattened surfaces 9, 12 of the ear tip 6 and the symmetry areas of the limb as a blunt irinkol.

109827/0935

BATH

Claims (2)

Patent application: 5 1. Drill driver screw with a flattened drill tip, which includes an approximately 3tumpfen 7 / inch and the opposite flattened holes. Cutting edge m form, from which, reaming, in front of 2u £ 3Viui3o spiral-shaped '! Juts largely down to the threadless. The shaft part is stretched, initially cylindrical and then conical bia sum maximum diameter of the drill tip, characterized by the fact that the flattened areas (9, 12) are broken as a broken iPlaoho a.uni-Johraubenspacheuende (11) lilη run in such a way that from the maximum diameter of the ßohrjx-i fcisa (6) there are flattened areas (9), which eixischlasson with the normal to the screw hole oinen r, ^r iiikel (. ^ ₀ ), which approximately do ^ i ^ lt OO is as large as the T / tnkel (/ ^ - i)> those with the aforementioned flattening on (9) achnoldende and for the screw: on: ;; - it; aonende (11) leading flattenings (12) form with the normal to the 3chraubach.se, whereby the flattened areas (9,12) running as a broken surface "a polygonal scrmoid edge (10,13) © r- 2. Drift screw according to Ansi ^ ruch 1, thereby aßk shows that the cutting surface (15) due to the same overlying chip flutes (14-), flattened areas (9,12) and Degronisunga areas (16,17) 109827/0935 BAD ORJQlNÄt - is delimited, the distance (a ₂ ) between the axis of symmetry of the screw and the cutting edges (10.13) is greater than the distance (a ^) between the axis of symmetry of the miter hood and the intersection of the chip grooves (14) with the boundary surfaces (16.17), 3 · drilling tapping screw according to claim 1, characterized gels: hen characterized in that the outlet of preferably spiral flute (14) rising at an axis of symmetry * 7inkel (cY].) ^E * · '-folgt and extending between the flat portions (9 »12) the BohrspitzQ (6) and dor 3ymmetrioobeno the Bohrtreibreabü create an obtuse angle designed clearance angle (CXO) 109827/0935 BATH ORIGINAL