CN205764065U - Stepped hole drill bit - Google Patents

Abstract

The utility model discloses a kind of stepped hole drill bit, including fluted drill and counterbore, the drill bit of described counterbore is provided with a counterbore being coaxial therewith, the axostylus axostyle of counterbore is provided with a countersunk screw hole that is vertical with its axis and that communicate with described counterbore, having a circle to lack on the handle of a knife of described fluted drill, the handle of a knife of fluted drill and described counterbore form the matched in clearance of precision and are locked by sunk screw.Stepped hole can be processed and formed at one time by this utility model, saving of work and time, and working (machining) efficiency is high, it is possible to fully ensure that the axiality of stepped hole；Fluted drill can change, it is to avoid fluted drill abrasion or cause the discarded waste of solid tool after fractureing.

Description

Step hole drill

technical field

The utility model relates to a machining tool, in particular to a stepped hole drill bit.

Background technique

Drills are one of the most commonly used tools in mechanical processing. In the processing of some special holes, it is troublesome to use existing drills, and the required accuracy cannot be achieved. For example, to process a coaxial step hole, and the step surface in the step hole for the plane. At present, there are generally two ways to process this stepped hole. One is to process the small hole with a twist drill, and then process the large hole with a countersink. The other is to use a small twist drill to process the small hole first, then use a twist drill to process the large hole to a certain depth, and finally use the end face countersink to countersink the bottom surface of the large hole. Among these two processing methods, the former needs to use two kinds of drill bits, which has low processing efficiency, while the latter needs to use three kinds of drill bits, which has lower processing efficiency, and it is difficult to guarantee the coaxiality of the stepped holes.

Contents of the invention

The purpose of the utility model is to provide a step hole drill bit, which can complete the step hole processing at one time, and can ensure that the two holes are concentric.

The technical solution to achieve the above object is: a stepped hole drill bit, including a twist drill and a flat countersink drill, a counterbore coaxial with the countersink is provided on the drill bit of the flat countersink, and a A countersunk screw hole perpendicular to its axis and communicating with the counterbore. There is a round segment on the handle of the twist drill. The handle of the twist drill forms a precise clearance fit with the counterbore and is formed by the countersunk screw. locking.

Further, there are two blades on the flat countersink, and the height of the blades is 4-5mm.

The utility model can process and shape the step hole at one time, saves labor and time, has high processing efficiency, and can fully ensure the coaxiality of the step hole; the twist drill can be replaced, which avoids the waste of the whole tool being discarded after the twist drill is worn or broken.

Description of drawings

Fig. 1 is a schematic structural view of an embodiment of the utility model.

Fig. 2 is a left side view of Fig. 1 .

Fig. 3 is a cross-sectional view at Fig. 1A-A.

Fig. 4 is a perspective view of the countersink drill in Fig. 1 .

In the figure: 1. Twist drill, 101. Twist drill handle, 102. Round, 2. Flat bottom countersink, 201. Blade, 202. Countersunk hole, 203. Countersunk screw hole, 204. Flat bottom countersink drill handle, 3. Countersunk head screws.

detailed description

Below in conjunction with accompanying drawing, the utility model is further described.

As shown in Figures 1-4, the utility model includes a twist drill 1 and a countersink drill 2, the drill bit of the countersink drill 2 is provided with a counterbore 202 coaxial with it, There is a countersunk screw hole 203 that is perpendicular to its axis and communicates with the counterbore, and there is a round segment 102 on the twist drill handle 101. 3 locks.

In the present utility model, there are two blades 201 on the flat countersink 2, and the height of the blades 201 is 4-5mm.

Claims (2)

1. A step hole drill bit, comprising a twist drill and a flat countersink, characterized in that: the drill bit of the flat countersink is provided with a counterbore coaxial with it, and a countersink with it is provided on the shaft of the flat countersink. A countersunk screw hole whose axis is vertical and communicated with the counterbore, a circular segment on the shank of the twist drill, the shank of the twist drill forms a precise clearance fit with the counterbore and is locked by the countersunk screw. 2. The stepped hole drill according to claim 1, characterized in that: there are two blades on the flat countersink, and the height of the blades is 4-5mm.