Twist drill for improving composite material-titanium alloy lamination hole making efficiency

Abstract

The utility model mainly relates to drilling of an aircraft composite material and metal material laminated structure, and belongs to the field of aircraft assembly. In particular to a twist drill capable of improving composite material-titanium alloy lamination hole making efficiency. The twist drill is of an integrated structure and is divided into a cutting edge section and a clamping handle section. Wherein the drill tip relief angle of the cutting edge section is an 18-degree multi-plane relief angle, the helical angle is 20 degrees, the core diameter is phi 1.08, and the groove type is a U-shaped groove; the clamping handle section is of a cylindrical structure. The problems of frequent drill bit tipping, clamping stagnation and the like in the composite material-titanium alloy laminated structure drilling process are effectively solved, and the risk of product surface quality damage caused by the problems is reduced.

Description

Technical Field

[0001] The utility model mainly relates to the hole making of the laminated structure of aircraft composite materials and metal materials, belonging to the field of aircraft assembly. Specifically, it is a twist drill for improving the hole making efficiency of composite-titanium alloy laminates. Background Technique

[0002] With the development of modern science and technology and the accelerating replacement and renewal of aircraft, new materials and new technologies are increasingly widely used in new aircraft. In particular, the proportion of lightweight metals such as composite materials and titanium alloys in the aircraft body structure is increasing. Therefore, improving the quality and efficiency of composite-titanium alloy laminate hole making is of great significance for improving the quality and efficiency of aircraft assembly.

[0003] Common composite-titanium alloy laminated structures in the aircraft manufacturing process are as Figure 1 shown. The glass fiber composite skin (hereinafter referred to as "composite skin") and the titanium alloy flat plate (hereinafter referred to as "titanium plate") are combined and bonded together through an adhesive, and the three materials are fastened and connected using bolts.

[0004] Currently, when making holes in composite-titanium alloy laminated materials or titanium alloys, a cemented carbide twist drill is mainly used to drill the primary hole, and a reamer is used to ream the hole. However, due to the relatively hard texture of the titanium alloy material, when an ordinary cemented carbide twist drill drills a titanium alloy or a composite-titanium alloy laminated structure, there are problems such as drill bit chipping, tool jamming, rapid tool wear and low tool life. Seriously, when the drill bit chips or jams, it will cause damage to the surface composite material layer. Content of the Utility Model

[0005] Purpose of the Utility Model

[0006] The utility model aims to solve the problems of low hole making efficiency and product damage caused by rapid wear and low life of the cemented carbide twist drill, and easy tool jamming and chipping during the hole making process of composite-titanium alloy laminates. The existing hole making methods for composite-titanium alloy laminates mainly have the problems of rapid tool wear, low tool life, and easy tool jamming and chipping.

[0007] In view of the above problems, the utility model proposes an improved twist drill for hole making of composite-titanium alloy laminates, which improves the stability and efficiency of hole making, reduces problems such as tool fracture, chipping, and jamming, and at the same time improves the tool service life and reduces the tool cost. It not only shortens the manufacturing cycle but also reduces the manufacturing cost.

[0008] Technical Solution

[0009] A twist drill for improving the hole-making efficiency of composite-titanium alloy laminates. The twist drill is of an integral structure and is divided into a cutting edge section and a clamping shank section. Among them, the back angle of the drill tip in the cutting edge section is an 18° multi-plane back angle, the helix angle is 20°, the core diameter is φ1.08 mm, and the flute profile is a "U" groove. The clamping shank section is of a cylindrical structure.

[0010] Furthermore, the twist drill is made of cemented carbide.

[0011] Furthermore, the length dimension of the twist drill is determined according to the working conditions.

[0012] Furthermore, the length of the twist drill is 70 mm. The length of the cutting edge section is 30 mm.

[0013] Furthermore, the diameter of the clamping shank section is determined according to the working conditions and the clamping range of the clamping tool.

[0014] Furthermore, the twist drill is suitable for cutting processing of through holes or blind holes.

[0015] Furthermore, when the twist drill is making holes in composite-titanium alloy laminates, it can maintain the same rotational speed at different material interfaces to complete hole-making.

[0016] Furthermore, when the twist drill is making holes in composite-titanium alloy laminates, it can keep the same feed rate throughout the titanium alloy laminate part to drill through the titanium alloy and obtain smaller burrs.

[0017] Technical effects

[0018] The twist drill described in the present utility model has been successfully applied to a certain aircraft functional structural part. Through a large number of usage verifications, the twist drill described in the present utility model has effectively solved problems frequently occurring during the hole-making process of composite-titanium alloy laminate structures, such as drill bit chipping and jamming, and reduced the risk of product surface quality damage caused thereby. In addition, compared with ordinary twist drills, the service life of the twist drill described in the present utility model has been greatly improved, and it has better wear resistance. Taking the hole-making of a laminate material with a thickness of 5 mm of composite material + 5 mm of titanium alloy as an example, the number of qualified holes continuously drilled by the twist drill described in the present utility model is at least 3 times that of ordinary cemented carbide twist drills continuously drilling qualified holes. Thereby, the tool usage cost is reduced, and the manufacturing cost of the entire product is indirectly reduced. In addition, the improvement of the twist drill life also reduces the number and time of workers replacing tools during the hole-making process, and the operation efficiency is improved, achieving the purpose of improving quality and efficiency, and obtaining good economic and social benefits. Description of the drawings

[0019] Figure 1 It is a schematic diagram of an aluminum alloy-composite material-titanium alloy laminate structure;

[0020] Figure 2 Schematic diagram of the structure of the twist drill involved in the present utility model;

[0021] Wherein: 1 - cutting edge section, 2 - clamping shank section, 3 - helix angle, 4 - core diameter;

[0022] Figure 3 Schematic diagram of the 18° multi-plane flank angle ( Figure 2 E-direction view in the figure);

[0023] Wherein: 5 - 18° multi-plane flank angle;

[0024] Figure 4 Schematic diagram of the drill tip protection belt ( Figure 2 B-B view in the figure);

[0025] Wherein: 6 - drill tip protection belt;

[0026] Figure 5 Schematic diagram of the U-shaped groove;

[0027] Wherein: 7 - "U" shaped groove. Specific implementation manners

[0028] To make the purpose, technical solutions and advantages of the implementation of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be described in more detail below with reference to the accompanying drawings in the embodiments of the present utility model. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions from beginning to end. The described embodiments are some, but not all, of the embodiments of the present utility model. The embodiments described below by referring to the drawings are exemplary and are intended to explain the present utility model, and should not be construed as a limitation of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts fall within the scope of protection of the present utility model. The embodiments of the present utility model will be described in detail below with reference to the drawings.

[0029] The improvements of the present utility model compared with the prior art include the following:

[0030] Change the drill tip flank angle on the twist drill to an 18° multi-plane flank angle. Delete the drill tip protection edge on the twist drill. Optimize the helix angle on the twist drill to 20°. Optimize the core diameter on the twist drill to φ1.08 mm and change the groove shape to a "U" shaped groove.

[0031] Change the back angle of the drill tip on the twist drill to an 18° multi-plane back angle. The changed back angle of the drill tip increases the rake angle of the cutting edge flank, making the cutting edge sharper, weakening the adhesion and wear of the flank, and improving the life of the cutting edge as much as possible under sufficient cutting strength. Delete the protective edge of the drill tip on the twist drill. The cutting edge of the drill tip adopts the structure of a "protective edge", which can reduce the rake angle of the actual cutting edge of the drill tip, improve the edge strength of the drill tip, make it not easy for the cutting edge of the drill tip to appear defects such as chipping and notches, and increase the life of the drill tip. In addition, this structure is also applicable to manual hole making, avoiding the situation of "drill jamming" and making the cutting more stable. Optimize and reduce the helix angle on the twist drill to 20°. The reduction of the helix angle shortens the chip evacuation path by 3.56%. While taking into account chip accommodation and chip evacuation, it also improves the strength and rigidity of the drill bit. Optimize the core diameter on the twist drill to φ1.08mm and change the groove shape to a "U" groove. Reducing the core diameter increases the chip accommodation space. At the same time, the chip evacuation groove shape is optimized to be closer to the "U" parabolic groove shape, making chip evacuation smoother, completely eliminating quality accidents such as the target hole becoming larger due to chip jamming and even tool breakage.

[0032] A method for using a twist drill, comprising the following steps:

[0033] Step 1, firmly clamp the twist drill using a hole-making tool such as a pneumatic drill.

[0034] Step 2, hold the pneumatic drill and align and press the drill tip of the twist drill against the hole site (or hole position line, initial hole, etc.).

[0035] Step 3, start the pneumatic drill and perform hole-making cutting.

[0036] Those skilled in the art of this technology can understand that, unless otherwise defined, all terms used here (including technical terms and scientific terms) have the same meaning as the general understanding of those of ordinary skill in the field to which this utility model belongs. It should also be understood that terms such as those defined in a general dictionary should be understood to have a meaning consistent with the meaning in the context of the prior art, and will not be interpreted with idealized or overly formal meanings unless defined as here. The above-described specific embodiments have further detailed the purpose, technical solution, and beneficial effects of this utility model. It should be understood that the above is only the specific embodiment of this utility model and is not used to limit this utility model. Any person skilled in the art may, within the spirit and principle of this utility model, use the disclosed technical content to make changes or modifications into equivalent embodiments with equivalent changes and apply them to other fields. However, any simple modification, equivalent change, and modification made to the above embodiments based on the technical essence of this utility model without departing from the technical solution content of this utility model, any modification, equivalent replacement, improvement, etc., shall be included in the protection scope of this utility model.

Claims

1. A twist drill for improving the hole-making efficiency of a composite material-titanium alloy laminate, characterized in that, The twist drill is of an integral structure and is divided into a cutting edge section and a clamping shank section; among them, the drill tip clearance angle of the cutting edge section is an 18° multi-plane clearance angle, the helix angle is 20°, the core diameter is φ1.08 mm, and the flute type is a "U" type flute; the clamping shank section is of a cylindrical structure.

2. The twist drill according to claim 1, characterized in that, The twist drill is made of cemented carbide.

3. The twist drill according to claim 1, characterized in that, The length of the twist drill is 70 mm; among them, the length of the cutting edge section is 30 mm.

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