SU1127704A2 - Drill - Google Patents

Abstract

Drill on the bus. St. No 992 S4, characterized in that, in order to improve the quality of the machined holes, the boring bar guiding elements are located between two groups of guiding elements of the drilling head, and the boring bar guiding elements are displaced in the radial direction by an angle of at least 20 &;deg; (L 1C vj

Description

The invention relates to metal cutting with chip removal, namely, tools for machining deep precision holes and can be used in mechanical engineering for machining precise holes on machines with increased spindle runout, for example, radial drilling.

Known drill on Aut. St. No. 992134, containing a bushing with guiding elements, at the end of which a drilling head is installed, which is provided with main and additional guiding elements spaced axially at a distance equal to or greater than the diameter of the tool 1.

The disadvantage of this design is the sequential arrangement of at least two boring bar guiding elements behind the second group of drilling head guiding elements, which leads to the formation of defects on the machined surface of the holes and to the extension of the conductor, sleeve, and deformation of the boring bar.

The aim of the invention is to increase the quality of the machined holes and improve processability.

The goal is achieved by the fact that in a drill containing a drill rod with guide elements mounted on its end facing the drill head with two groups of guide elements spaced axially at a distance equal to or greater than the diameter of the drill bit, the guide elements of the boring bar are located between the two groups of guiding elements of the drilling head, and the guiding elements of the borschtangi are offset relative to the guiding elements of the drilling head in the radial direction by an angle of at least 20 °.

FIG. 1 shows a drill at the articulation of the boring bar and the drilling head by means of end grooves - protrusions, general view; in fig. 2 shows section A-A in FIG. I; in fig. 3 - the same, a drill at the articulation of the boring bar and the drilling head with the help of splines, general view; in fig. 4 shows a section BB in FIG. 3; in fig. 5 is a view along arrow B in FIG. 3; in fig. 6 shows a drill when articulating a boring bar and a drilling head by means of a spherical surface, a general view.

Drill With articulation of borshtangi and; turning head through end grooves - protrusions (Figs. 1 and 2) contains boring bar I articulated with drilling head 2 by means of end grooves - protrusions 3. Drill head 2 contains cutting 4 and two groups of guide elements 5 and 6. Groups of guide elements 5 and 6 are axially spaced apart by a distance equal to or

larger drilling diameter, which provides an autonomous base of the drilling head 2. Between the two groups of guide elements of the drilling head, there are guide elements 7 and boring bars 1, radially displaced relative to the guides 5 and 6, of the drilling head, on the front grooves.

The drill with articulation of borschtangi and drilling head by means of slits (Fig. 3-5) contains boring bar 1 articulated with the drilling head by means of splines 8 .. Drilling head 2 contains cutting 4 and two groups of guide elements 5 and 6. Groups of guides 5 and 6 are axially spaced apart from each other at a distance equal to or greater than the drilling diameter, which provides an independent base for the drilling head 2. The guide elements 7 are located between two groups of guide elements 5 and 6 of the drilling head 2 w 1, offset radially with respect to the guide members 5 and 6, the drilling head (Fig. 4). The guiding elements 6 of the drilling head are installed in the through-holes 9 of Borschtang I and fixed in the slots of the body of the drilling head by means of screws 10. The seal 11 serves to seal the inner surface of the drill from which external high-pressure coolant is applied during operation. The reverse arrangement is also possible, in which the boring bar guiding elements are installed in the through-holes of the drilling head. This is shown in FIG. 6 by the example of a drill in which the boring bars are articulated with the drilling head by means of a spherical surface 12. The drilling head 2 comprises two groups of guide elements 5 and 6, which are axially spaced apart from each other at a distance equal to or greater than the drilling diameter. The guide elements 7 of the boring bars 1 are mounted in the through-holes 9 of the drilling head and secured in the slots of the borings by means of screws 10.

All three of the above design drills work the same way. Coolant flow is supplied to the annular gap between the walls of the machined hole and the outer surface of the boring bar.

The drill (or part) is driven by the drive of the machine. The torque from the boring bar to the drilling head is transmitted by means of slots - protrusions (Fig. 3) or by means of guide elements installed in - through

boring windows {or drilling head).

The additional forces arising from misalignment of the machine spindle (or the oil receiver spindle in the case of ejector drills) and the conductor sleeve are closed on the guide boring bars (Fig. 1.3). These guiding elements degrade the surface quality of the hole machined by the cutting and the first group of guiding elements of the drilling head due to the additional forces due to misalignment. However, the second group of guide elements of the drilling head, located in the axial direction behind the group of guide elements of the boring bar, makes it possible to correct these defects due to the force effect on the surface being treated. The normal forces acting on the guiding elements of the drilling head are a redistribution of the cutting force during drilling and are therefore significantly greater than the normal forces acting on the boring bar guiding elements and arising from the misalignment of the boring bar and the conductor sleeve. This allows the guide elements of the drilling head to fully correct the defects of the boring guide elements. Coolant flow to the drill bit lubricates and cools the cutting and guiding

the elements and chips are retracted along the inner surface of the drill.

Sequentially parallel

to the arrangement of the guide elements, the length of the conductor sleeve will be determined only by the distance between the two groups of the guide elements of the drill bit. lilny head. At the same time, a greater amount of plastic deformation is transferred to the second group of guide elements,

This makes it possible to completely eliminate the surface defects of the hole left by the guide elements of the borschtangi. To improve the smoothing process, the boring guide elements are radially displaced relative to the drilling head guide elements by an angle of at least 20 °. The magnitude of this angle is due to the angular position of the two guides with the exception of their mutual overlap (20 ° - this angle is greater than the angular size of two radially arranged guide elements).

The application of the proposed construction makes it possible to improve the accuracy of the machined holes, especially at large misalignments of the boring rods and the conductor sleeve. Or the large beats of the machine spindles.

fe. g

FIG. 6

Claims (1)

DRILL St. No. 992134, characterized in that, in order to improve the quality of the machined holes, the guide elements of the boring bar are located between two groups of guide elements' of the drill head, and the guide elements of the boring bar are offset relative to the guide elements of the drill head in a radial direction by at least 20 °. SU „., 1127704 FIG. /