SU1696175A1 - Multiflute drill - Google Patents

Abstract

The invention relates to the field of metal cutting and can be used for drilling holes. The purpose of the invention is to simplify the design. A drill countersink contains a drill with a working part 1, on which screw grooves are made, and a cylindrical shank 2 and a countersink assembly, which includes a countersink body 3 and a removable cutting plate 4. On the side of a part, the countersink body 3 is cut with radial cuts and is a collet . On the shank side, the countersink body is made in the form of a threaded sleeve 6. The outer surface 7 of the collet in the area adjacent to the threaded sleeve 6 is made conical. The diameter of the hole in the housing 3 countersink is larger than the diameter of the drill. The cutting plate 4 is installed in the radial slot of the body of the countersink 3 and, with its non-working part, is placed in the screw groove of the working part 1 of the drill. To exclude the possibility of turning the drill, the cutting plate 4 is in contact with the two side surfaces of the helical groove, provided that the dimensions of the cutting plate are related to the geometrical parameters of the helical groove of the drill. Zil. with

Description

The invention relates to the field of metal cutting and can be used for machining holes.

The aim of the invention is to simplify the design.

FIG. 1 shows drill drill, general view; in fig. 2 is a view A of FIG. one; in fig. 3 - development of the screw groove of the drill and the positioning of the countersink cutting plate in it.

The countersink drill bit contains a drill with working part 1, on which screw grooves are made, and cylindrical shank 2 and countersink assembly, including a countersink body 3 and a replaceable cutting core 4. From the working part, the countersink body is cut by non-radial slots 5 and is a collet.

From the side of the shank, the countersink body is made in the form of a threaded sleeve 6. The outer surface 7 of the collet in the area adjacent to the threaded sleeve is made conical. The diameter of the hole in the housing 3 countersink larger than the diameter of the drill. The cutting plate 4 is installed in the radial slot 5 of the body 3 of the countersink and its non-working part is placed in the screw groove of the working part 1 of the drill. A threaded bushing 6 of the countersink housing 3 is screwed on with an internal thread 8, a transitional mandrel 9 in contact with the conical outer surface 7 of the countersink housing. The outer surface of the transition mandrel 9 is designed to fasten the tool in the chuck of the machine, and the inside - contains a hole, coinciding with

about

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diametrically with the shank 2 of the drill and has a threaded section 10 under the locking screw 11 on the rear side. To exclude the possibility of turning the drill, the cutting plate must be in contact with both surfaces of the helical groove. This requirement is fulfilled if the size of the cutting insert is related to the geometrical parameters of the helical groove of the drill by the equation b I sin о) + h cos to

where b is the width of the screw groove of the drill, mm;

o is the angle of inclination of the screw groove of the drill;

h is the thickness of the cutting plate, mm; I is the length of the cutting plate in cross section, passing through the points of its Contacts with the screw groove of the drill, mm.

When assembling the tool body 3 countersink wear on the drill, enter the shank 2 drills into the hole of the adapter mandrel 9 and screw the adapter mandrel onto the threaded bushing 6 of the cylinder core 3. After that, insert the cutting plate 4 into the slot 5 of the zaigus honor of the body 3, turning the drill bit with it, so that the non-working part of the cutting plate 4 fits into the screw groove of the drill. Turning the drill bit n, respectively, moving it in the axial direction, set the drill bit in a position in which the cutting plate touches the exit surface of the helical groove excluding the axial movement of the drill bit.

The cutting plate, the dimensions of which are made according to the above equation, concerns both sides of the helical groove profile and eliminates the possibility of turning the drill. Since the diameter of the hole in the body of the countersink is larger than the diameter

drill bits, body drill with a drill is not in contact. The position of the drill is determined by the placement of its shank in the hole of the transition mandrel 9 and the location of the non-working part of the cutting plate 4 in the helical groove of the drill. When tightening the thread 8 on the thread of the sleeve 6, the transition mandrel 9 acts on the conical surface 7 of the countersink body, squeezes it

collet and secures the cutting plate 4 in the slot 5. Screwing the screw 11 into the thread 10 until it stops in the drill shank, finally fix its position.

In the process of cutting under the influence of

5 cutting forces the thread of the adapter is tightened on the thread of the countersink body, which increases the reliability of the cutting attachment

plates.

Claims (1)

Invention Formula 0 A countersink drill in which the drill with screw grooves is placed in the axial hole of the countersink body, and the replaceable cutting plate is fixed on the countersink case, characterized in that 5 in order to simplify the design, the countersink body is made in the form of a collet with radial slots, the cutting plate is installed in the slot of the collet, and the non-working part of the cutting plate is located in the helical groove 0 drill widths determined by equation b I sin a) + h cos a where b is the width of the screw groove of the drill, mm; 5th - the angle of the screw grooves drill; h is the countersink cutting plate thickness, mm; I - the length of the cutting plate in cross section, 0 passing through the point of its contact with the screw groove of the drill, mm. 4 3.1b at 2yu M LL ± L Phi. 111 Thebes. I Fm