CN212822925U - Twist drill - Google Patents

Abstract

The utility model provides a twist drill belongs to mechanical technical field. It has solved the current not good problem of fluted drill structural stability. This twist drill includes the body of rod and the drill point of locating the body of rod front end, be equipped with the axial round hole on the terminal surface before the body of rod, the drill point rear end has the convex body, the convex body inserts and inlays in the axial round hole, still run through the radial pinhole that has and axial round hole intercommunication on the body of rod lateral wall, be equipped with the pin in the radial pinhole, the pin tip sticiss on the convex body lateral wall, the cold water hole has in the body of rod, cold water hole front end intercommunication axial round hole, the convex body anterior segment is the cylinder portion that matches with the axial round hole, the convex body back end is for being the pyramis of solid circular cone form, the pyramis diameter is diminished gradually to the back before by, be equipped with the groove of stepping down that is the bar on the axial round hole lateral wall, the groove front end of stepping down. This auger bit stable in structure.

Description

Twist drill

Technical Field

The utility model belongs to the technical field of machinery, a drill bit, especially a twist drill bit is related to.

Background

Twist drills are tools for drilling round holes in workpieces by rotary cutting relative to a fixed axis, and are known as twist drills because the chip flutes are helical.

The conventional twist drill is a twist drill with a replaceable drill bit as disclosed in chinese patent library [ application number: 201520317344.5, comprising a drill handle and a drill body, wherein the end of the drill body is provided with a replaceable drill, characterized in that the inner end of the drill is axially provided with a connecting column, the end of the drill body is axially provided with a connecting hole matched with the connecting column, the outer side wall of the connecting column is provided with a plurality of convex protrusions, the side wall of the connecting hole is provided with a strip-shaped groove matched with the protrusions, and the protrusions are embedded in the strip-shaped groove; and a through cooling hole is axially formed in the middle of the drill shank and communicated with the connecting hole.

In the drill bit, the convex body is embedded in the strip-shaped groove to form a certain seal, cooling water entering from the cooling hole has certain pressure, and the pressure impacts on the convex body to enable the convex body to have a moving trend, so that the convex body is loosened in time and the use is influenced.

SUMMERY OF THE UTILITY MODEL

The utility model aims at solving the problems in the prior art, and provides a twist drill bit with stable structure.

The purpose of the utility model can be realized by the following technical proposal: a twist drill comprises a rod body and a drill tip arranged at the front end of the rod body, wherein an axial round hole is formed in the front end face of the rod body, a convex body matched with the axial round hole is arranged at the rear end of the drill tip, the convex body is inserted and embedded in the axial round hole, a radial pin hole communicated with the axial round hole is further formed in the side wall of the rod body in a penetrating mode, a pin is arranged in the radial pin hole, the end portion of the pin is tightly pressed on the side wall of the convex body, a cold water hole is axially arranged in the rod body, the front end of the cold water hole is communicated with the axial round hole, and the rear end of the cold water hole extends to the rear end face of the rod body; the lateral wall of axial round hole on be equipped with the groove of stepping down that is the bar, the groove length of stepping down extends along the axis of axial round hole, the front end in groove of stepping down extends to the body of rod preceding terminal surface, and the rear end in groove of stepping down extends to just right with the pyramis.

During the use, cooling water gets into and flows into axial round hole by cold water hole rear end, discharges into the breach inslot through the groove of stepping down under the pyramis water conservancy diversion effect to cool off the drill point drilling.

Set up the downward pyramis that diminishes gradually of diameter in axial round hole cooling water income position to make rivers to disperse all around and discharge through the groove of stepping down, thereby effectively reduce the impact of cooling water to the convex body, reduce the relative motion between convex body and pin and the body of rod, make the convex body lock steadily in the axial round hole, improve the structural stability of this drill bit, in order to ensure the stability of its work.

In the twist drill, the receding grooves are at least two and are uniformly distributed along the circumferential direction of the axial round hole, so that cooling water is smoothly discharged.

In the twist drill, the cross section of the abdicating groove is arc-shaped.

In the twist drill, the side wall of the rod body is provided with the spiral chip groove, and the rod body is internally provided with the drain hole which enables the chip groove to be communicated with the cold water hole, so that cooling water in the cold water hole can flow into the chip groove to cool the whole rod body.

In the twist drill, the front end face of the rod body is integrally formed with two convex blocks, the two convex blocks are arranged oppositely and form a notch groove with the front end face of the rod body, the drill point is provided with a clamping block clamped and embedded in the notch groove, a gap exists between the clamping block and the front end face of the rod body, and the convex body is arranged on the clamping block. The fixture block is matched with the notch groove, so that the positioning effect of the drill point can be enhanced.

In the twist drill, the drill tip is made of a hard alloy material.

Compared with the prior art, this twist drill bit sets up the downward pyramis that diminishes gradually of diameter through setting up the awl portion in axial round hole cooling water income position to make rivers to disperse all around and discharge through the groove of stepping down, thereby effectively reduce the impact of cooling water to the convex body, reduce the relative motion between convex body and pin and the body of rod, make the convex body lock steadily in the axial round hole, improve the structural stability of this drill bit, in order to ensure its job stabilization nature.

Drawings

Fig. 1 is a schematic diagram of an exploded structure of a twist drill.

Fig. 2 is a schematic sectional view of the twist drill.

Fig. 3 is an enlarged schematic view of a structure at a in fig. 2.

In the figure, 1, a rod body; 1a, cold water holes; 1b, a chip groove; 1c, a drain hole; 1d, axial round holes; 1d1, a relief groove; 1e, radial pin holes; 1f, a bump; 2. drilling a tip; 2a, a drill part; 2b, a clamping block; 2c, convex body; 2c1, a cylindrical portion; 2c2, taper; 3. a pin.

Detailed Description

The following are specific embodiments of the present invention and the accompanying drawings are used to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

As shown in fig. 1, the twist drill includes a rod 1 and a tip 2 disposed at a front end of the rod 1. In this embodiment, the drill tip 2 is made of cemented carbide material and the shank 1 is made of stainless steel material.

Wherein, be equipped with along the cold water hole 1a of axial setting in the body of rod 1, cold water hole 1a rear end extends to body of rod 1 rear end face, is equipped with spiral helicine chip groove 1b on the body of rod 1 lateral wall, and is equipped with the wash port 1c that makes chip groove 1b and cold water hole 1a intercommunication in the body of rod 1, makes the cooling water in cold water hole 1a can flow into chip groove 1b, cools off whole body of rod 1. In the actual product, the drainage holes 1c are plural and distributed along the length direction of the chip grooves 1 b.

The drill point 2 is an integrated structure, and consists of a base and a drill part 2a arranged on the base, and the base is positioned between the drill part 2a and the rod body 1. The base comprises fixture block 2b and the convex body 2c of setting on fixture block 2b, as shown in fig. 1 and 3, is equipped with axial round hole 1d on the preceding terminal surface of the body of rod 1, and the front end intercommunication axial round hole 1d of cold water hole 1 a. The shape and the size of the convex body 2c are matched with the axial round hole 1d, and the convex body 2c is inserted and embedded in the axial round hole 1 d. Still run through on the body of rod 1 lateral wall have with the radial pinhole 1e of axial round hole 1d intercommunication, be equipped with pin 3 in the radial pinhole 1e, and 3 tip sticiss on the convex body 2c lateral wall of pin to better location convex body 2 c. The integrated into one piece has two lugs 1f on the preceding terminal surface of the body of rod 1, and lug 1f length is along body of rod 1 axial extension, and two lugs 1f are just to setting up and constitute a breach groove with the preceding terminal surface of the body of rod 1, and the shape and the size of fixture block 2b all match with the breach groove, and fixture block 2b inlay card is in the breach groove, and at this moment, has the clearance between the preceding terminal surface of fixture block 2b and the body of rod 1.

To explain further, as shown in fig. 1 and 2, the convex body 2c is composed of a front section and a rear section, the front section of the convex body 2c is a cylindrical portion 2c1 matching with the axial circular hole 1d, the rear section of the convex body 2c is a tapered portion 2c2 in a solid conical shape, the diameter of the tapered portion 2c2 is gradually reduced from the front to the rear, and the maximum diameter of the tapered portion 2c2 is the same as the diameter of the cylindrical portion 2c 1. The side wall of the axial round hole 1d is provided with a strip-shaped abdicating groove 1d1, the length of the abdicating groove 1d1 extends along the axis of the axial round hole 1d, the front end of the abdicating groove 1d1 extends to the front end face of the rod body 1, and the rear end of the abdicating groove 1d1 extends to be opposite to the cone part 2c 2. At least two of the receding grooves 1d1 are uniformly distributed along the circumferential direction of the axial round hole 1d, so that cooling water can be smoothly discharged. In this embodiment, it is preferable that the number of the relief grooves 1d1 is 4, and the cross section of the relief groove 1d1 is circular arc.

When the drill bit is used, cooling water enters from the rear end of the cold water hole 1a and flows into the axial round hole 1d, and is discharged into the notch groove through the abdicating groove 1d1 under the flow guiding effect of the cone part 2c2, so that the drill bit 2 is cooled in a drilling mode. Set up the downward toper part 2c2 that diminishes of diameter at axial round hole 1d cooling water income position to make water flow to disperse all around and discharge through letting the groove 1d1, thereby effectively reduce the impact of cooling water to convex body 2c, reduce the relative motion between convex body 2c and pin 3 and the body of rod 1, make convex body 2c lock in axial round hole 1d steadily, improve the structural stability of this drill bit, in order to ensure its job stabilization nature.

The specific embodiments described herein are merely illustrative of the spirit of the invention. Various modifications, additions and substitutions for the specific embodiments described herein may be made by those skilled in the art without departing from the spirit of the invention or exceeding the scope of the invention as defined in the accompanying claims.

Claims (6)

1. A twist drill comprises a rod body (1) and a drill point (2) arranged at the front end of the rod body (1), wherein an axial round hole (1d) is formed in the front end face of the rod body (1), a convex body (2c) matched with the axial round hole (1d) is arranged at the rear end of the drill point (2), the convex body (2c) is inserted and embedded in the axial round hole (1d), a radial pin hole (1e) communicated with the axial round hole (1d) is further penetrated through the side wall of the rod body (1), a pin (3) is arranged in the radial pin hole (1e), the end part of the pin (3) is tightly pressed on the side wall of the convex body (2c), a cold water hole (1a) arranged along the axial direction is formed in the rod body (1), the front end of the cold water hole (1a) is communicated with the axial round hole (1d), the rear end of the cold water hole (1a) extends to the rear end face of the rod body (1), and the twist drill is characterized in that the front section of the convex body (, the rear section of the convex body (2c) is a taper part (2c2) in a solid conical shape, the diameter of the taper part (2c2) is gradually reduced from front to back, and the maximum diameter of the taper part (2c2) is the same as that of the cylindrical part (2c 1); the lateral wall of axial round hole (1d) on be equipped with the groove of stepping down (1d1) that is the bar, the axis of the groove of stepping down (1d1) length along axial round hole (1d) extends, the front end of the groove of stepping down (1d1) extends to body of rod (1) preceding terminal surface, and the rear end of the groove of stepping down (1d1) extends to just right with pyramis (2c 2).

2. The twist drill according to claim 1, wherein the relief grooves (1d1) are at least two and are uniformly distributed along the circumferential direction of the axial circular hole (1 d).

3. Twist drill according to claim 1 or 2, characterized in that the relief groove (1d1) has a circular arc-shaped cross-section.

4. The twist drill according to claim 1 or 2, wherein the side wall of the shank (1) is provided with a helical chip groove (1b), and the shank (1) is provided with a water drain hole (1c) for communicating the chip groove (1b) with the cold water hole (1 a).

5. The twist drill according to claim 1 or 2, wherein the front end surface of the rod body (1) is integrally formed with two protrusions (1f), the two protrusions (1f) are oppositely arranged and form a gap groove with the front end surface of the rod body (1), the drill tip (2) is provided with a fixture block (2b) which is clamped in the gap groove, a gap exists between the fixture block (2b) and the front end surface of the rod body (1), and the protrusion (2c) is arranged on the fixture block (2 b).

6. Twist drill according to claim 1 or 2, characterized in that the drill tip (2) is made of cemented carbide material.

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