CN211840286U - Double-edge gun drill - Google Patents

Abstract

The utility model provides a twolip gun drill, belongs to deep hole processing technology field, the drill point (1) the place ahead of twolip gun drill is equipped with guide section drill point (2), be equipped with three margin (3) on drill point (1) and the guide section drill point (2) of twolip gun drill, the drill point (1) of twolip gun drill is equipped with drill point outer fringe circular arc (4). The utility model improves the drill point part, thereby improving the positioning and guiding effect of the drill point; reducing the axial force; thereby achieving the purpose of improving the straightness of the processed hole.

Description

Double-edge gun drill

Technical Field

The utility model belongs to the technical field of deep hole processing, when the straightness accuracy requirement of concretely relates to twolip gun drill processing deep hole is higher, can adopt this type of drill point.

Background

When the double-edge gun drill is used for processing deep holes, the deviation of the straightness of the holes is 1-2/1000mm under an ideal state. If the straightness requirement is higher, it is difficult to realize. When a diesel engine factory processes a large-displacement diesel engine, the diameter of a main oil passage hole of a cylinder body of the diesel engine is 28mm, the depth of the main oil passage hole is 1000mm, the main oil passage hole can be processed only by using a double-edge gun drill, and the length or the efficiency of other cutters can not meet the basic requirements of customers. However, when the standard double-edged gun drill is used for machining, the straightness of the machined hole is poor, and the precision required by the drawing cannot be achieved.

In the field of diesel engines, engines are mainly used on heavy trucks or yachts. The engine cylinder body is mainly made of cast iron, including gray iron and vermicular cast iron. The cutter for processing the main oil passage hole of the cylinder body is a double-edge gun drill, and the standard double-edge gun drill has poor straightness for processing the hole due to the fact that the depth of the oil passage hole of the cylinder body is deep, and the requirement is difficult to achieve. Or the counter drill is adopted twice, but the workpiece needs to be rotated, repositioned, clamped and fast-forwarded, so that the production efficiency is seriously reduced.

SUMMERY OF THE UTILITY MODEL

In order to solve the technical problem, the utility model provides a double-edge gun drill, which improves the positioning and guiding effect of the drill tip by improving the drill tip part; reducing the axial force; thereby achieving the purpose of improving the straightness of the processed hole.

The utility model adopts the following technical scheme:

a guide section drill point is arranged in front of a drill point of the double-edge gun drill, three blade zones are arranged on the drill point of the double-edge gun drill and the guide section drill point, and the drill point of the double-edge gun drill is provided with a drill point outer edge arc.

Further, the guide section drill point diameter is 1/2 of the bore diameter being machined.

Further, the angle of the margin to the rake face is 50 °.

Further, the width of the cutting edge is 0.06x of the diameter of the outer circle.

Further, the guide section tip clearance angle is a standard plane relief surface, and is added with a 0.1dx30 ° chamfer, or in the form of r0.1d.

Further, the step part between the drill point of the double-edge gun drill and the drill point of the guide section is a 60-degree sharp angle, and a 3-degree axial relief angle and a 8-degree radial relief angle are adopted.

Furthermore, the drill point of the guide section is split, the length of the edge on one side is larger than the radius, and the length of the edge on the other side is smaller than the radius.

The utility model discloses an advantage and effect do:

1. the standard drill point has two margins, and the improved drill point has three margins. The guiding performance is improved.

2. The standard drill tip has a diameter and the modified drill tip increases the small end diameter. The centering performance is improved.

3. The standard drill point has a chisel edge and the modified drill point has no chisel edge. The axial force of the gun drill during processing is reduced. The straightness of the hole processed by the gun drill is better.

4. The standard drill point external support turning point is not provided with a circular arc, so that tipping is easy during processing of the vermicular iron, and the improved drill point external support turning point is provided with a circular arc design, so that the strength of the external circle turning point is improved, and the service life of the gun drill is prolonged.

Drawings

FIG. 1 is a schematic view of a standard drill point of a double-edged gun drill;

FIG. 2 is a schematic view of the structure of the drill point of the double-edged gun drill of the present invention;

FIG. 3 is a schematic view of a land distribution;

FIG. 4 is a schematic view of the transition step between the drill tip and the small drill tip;

fig. 5 is a schematic structural diagram of a small drill point head.

The components in the figure: 1 is a drill point, 2 is a guide section drill point, 3 is a cutting edge, 4 is an arc at the outer edge of the drill point, and 5 is a chisel edge.

Detailed Description

The present invention will be further explained with reference to the drawings and the embodiments.

As shown in fig. 1 and 2, is a comparison of the modified drill tip with a standard drill tip.

A guide section drill point 2 is arranged in front of a drill point 1 of a double-edge gun drill, three blade bands 3 are arranged on the drill point 1 and the guide section drill point 2 of the double-edge gun drill, and a drill point outer edge circular arc 4 is arranged on the drill point 1 of the double-edge gun drill.

1/2, the outer diameter of the positioning drill point is the diameter of the processed hole; the positioning drill point back angle is a standard plane back tool face, and a chamfer angle of 0.1dx30 degrees is added. It can also be made in R0.1d form, which is slightly more effective, but the tool manufacture is more complicated.

The angle between the increased margin and the rake face is 50 degrees; the width of the cutting edge =0.06x outer circle diameter; the three margins may be chosen to be of the same width, or the minor margins may be slightly wider.

The guide section 2 clearance angle is a standard plane clearance face, and is added with a chamfer angle of 0.1dx30 degrees or a form of R0.1d.

Step portion between drill point 1 and the guide section drill point 2 of twolip gun drill is 60 sharp angles, adopts 3 axial relief angles and 8 radial relief angles.

The guide section drill point 2 adopts a split design, and the axial force is reduced. Note that the edge length on one side is greater than the radius and the edge length on the other side is less than the radius.

Claims (7)

1. A double-edged gun drill characterized in that: the double-edge gun drill is characterized in that a guide section drill point (2) is arranged in front of a drill point (1) of the double-edge gun drill, three edge strips (3) are arranged on the drill point (1) and the guide section drill point (2) of the double-edge gun drill, and a drill point outer edge circular arc (4) is arranged on the drill point (1) of the double-edge gun drill.

2. A double-edged gun drill as defined in claim 1, wherein: the diameter of the guide section drill point (2) is 1/2 of the diameter of the bore to be processed.

3. A double-edged gun drill as defined in claim 1, wherein: the angle between the cutting edge (3) and the front cutter face is 50 degrees.

4. A double-edged gun drill as defined in claim 1, wherein: the width of the cutting edge is 0.06x of the diameter of the excircle.

5. A double-edged gun drill as defined in claim 1, wherein: the back angle of the drill point (2) of the guide section is a standard plane back tool face, and a chamfer angle of 0.1dx30 degrees or a form of R0.1d is added.

6. A double-edged gun drill as defined in claim 1, wherein: step portion between drill point (1) and the guide section drill point (2) of twolip gun drill is divided into 60 sharp angles, adopts 3 axial relief angles and 8 radial relief angles.

7. A double-edged gun drill as defined in claim 1, wherein: the drill point (2) of the guide section is split, the length of the edge on one side is larger than the radius, and the length of the edge on the other side is smaller than the radius.

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