Low-speed rotating tool bit structure suitable for vacuum environment

Abstract

The utility model provides a low-speed rotating tool bit structure suitable for a vacuum environment, which comprises a tool body and a plurality of cutting edges distributed on the tool body, and the cutting edges are uniformly distributed on the tool body in the circumferential direction; each cutting edge comprises a front angle representing the inclination degree of the front tool face, a rear angle representing the friction degree of the rear tool face in the cutting process, a side angle representing the inclined cutting angle of the cutting edge in the inclined cutting process and a tool nose according to the motion mode of the cutting edge; the side angle is set to be 24.9-25.1 degrees, and it is guaranteed that in a vacuum environment and under the low-speed condition that the rotating speed of a cutter shaft is not larger than 50 degrees per second, a cutter tip can conduct automatic feeding cutting under the action of constant pressure.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of machining, in particular to the field of low-speed rotating tool bit in vacuum environment. BACKGROUND

[0002] With the development of China's aerospace technology, the demand for drilling maintenance operation in the extravehicular vacuum environment is put forward.

[0003] For the drilling operation of the extravehicular vacuum environment equipment, research is needed for the vacuum environment, drilling object and rotation speed, and relevant parameter research is carried out, and a low-speed rotating tool bit structure suitable for vacuum environment is proposed to solve the technical problems of ensuring drilling effectiveness and drilling surface finish in the extravehicular vacuum environment.

[0004] At present, the technology of drilling and repairing aircraft in space environment is applied for the first time in China, and there is no related tool bit development basis. In foreign aircraft drilling and repairing, the center drill bit method is used for operation. The center drill bit method has high hole turning efficiency when operating on hard objects, but the cutting material is small in amount and difficult to collect in the vacuum environment. INVENTION CONTENTS

[0005] The technical problem solved by the utility model is to provide a low-speed rotating tool bit structure suitable for vacuum environment, and the purpose of the low-speed rotating tool bit structure suitable for vacuum environment is to ensure low-speed drilling operation in the extravehicular vacuum environment.

[0006] The technical solution of the utility model is: a low-speed rotating tool bit structure suitable for vacuum environment, comprising a tool body and tool edges distributed on the tool body, the number of tool edges is multiple, and the tool edges are uniformly distributed in the circumferential direction on the tool body; each tool edge comprises a rake angle representing the inclination degree of the rake face, a relief angle representing the friction degree of the relief face in the cutting process, a side angle representing the cutting angle of the tool edge in the cutting process, and a tool tip according to the movement mode of the tool edge; the side angle is set to 24.9°-25.1°, so that under the condition of low speed of the tool shaft rotation speed not greater than 50° / s in the vacuum environment, the tool tip can be self-fed cutting under the action of constant pressure.

[0007] Preferably, the side angle is set to 25°.

[0008] Preferably, the rake angle of the tool edge is set to 59.9°-60.1°, and the drilling efficiency of the tool bit is improved.

[0009] Preferably, the rake angle of the tool edge is set to 60°.

[0010] Preferably, the relief angle of the tool edge is set to 28.4°-28.6°, and the drilling surface finish is improved.

[0011] Preferably, the relief angle of the tool edge is set to 28.5°.

[0012] Preferably, the tip is a front end round head with a diameter ranging from 0.5mm to 1mm.

[0013] Preferably, the bottom of the shank is provided with an inner hexagonal hole.

[0014] Preferably, the shank and the blade are coated with red vacuum pigment on the outside.

[0015] The utility model has the beneficial effects compared with the prior art:

[0016] The utility model discloses a low-speed rotating tool bit structure suitable for vacuum environment, which is an important guarantee for implementing low-speed drilling operation in the extravehicular vacuum environment.

[0017] For the in-orbit use scene in China, the low-speed circular drilling mode is adopted for operation, the drilling area is large, and the cutting object is an integral whole, which is convenient to collect in the vacuum environment. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 Fig. 1 is a schematic view of a low-speed rotating tool bit structure suitable for vacuum environment;

[0019] Figure 2 Fig. 2 is a schematic view of the blade distribution and installation interface;

[0020] Figure 3 Fig. 3 is a schematic view of the rake angle, relief angle and side angle of the blade;

[0021] Figure 4 Fig. 4 is a schematic view of the rake angle of the blade;

[0022] Figure 5 Fig. 5 is a schematic view of the relief angle of the blade;

[0023] Figure 6 Fig. 6 is a schematic view of the side angle of the blade;

[0024] Figure 7 Fig. 7 is a schematic view of the self-feeding principle of the blade. DETAILED DESCRIPTION

[0025] The utility model will be further described below in combination with the embodiments.

[0026] The utility model provides a low -speed rotating tool bit structure of suitable vacuum environment, for guaranteeing the safety of astronaut extravehicular environment drilling operation, the low speed condition of tool shaft rotation speed not more than 50 DEG / s, and the cutting feed of blade is independently completed after the blade receives constant pressure. Figure 1 )。

[0027] 1) tool body

[0028] The tool body is provided with an inner hexagonal hole with a diameter of 20mm and a bottom spacing of 11mm, which facilitates installation and meets the transmission of rotary force. The cutting edges are uniformly distributed on the top of the tool body.

[0029] 2) cutting edge

[0030] The cutting edge has a front angle 21, a back angle 22, a side angle 23 and a cutting tip 24. Figure 3 The front angle represents the inclination of the rake face, and is the angle between the rake face and the surface of the material being cut. The larger the front angle, the sharper the cutting edge, but the strength of the cutting edge will decrease. The back angle is the angle between the relief face and the surface of the material being cut, and represents the degree of friction of the relief face during cutting. The larger the back angle, the less the friction, the better the surface quality of the processed surface, and the sharper the cutting edge. The side angle is the angle between the side of the cutting edge and the feed direction of the tool bit, and represents the angle of inclination of the cutting edge during cutting. The smaller the side angle, the smaller the cutting force, and the higher the precision of the inclined cutting.

[0031] According to the characteristics of the small-density metal material selected for the outer shell of the extravehicular equipment, a large angle is selected in the design of the front angle of the cutting edge, which can reduce the stress and heat stress during the extrusion of the metal material by the inclined cutting edge, effectively improving the smoothness of the cutting surface. A large angle is selected in the design of the back angle of the cutting edge to improve the surface quality of the processed surface. A small angle is selected in the design of the side angle of the cutting edge to reduce the cutting force and improve the processing precision.

[0032] According to the movement mode of the tool bit, 12 cutting edges are uniformly distributed on the circumference of the tool body. One cutting edge is provided every 30 DEG Figure 2), according to the low-speed rotation characteristics of the tool shaft speed, the structure of the blade is innovatively designed (the side angle of the blade is 24.9°-25.1°, the rake angle of the blade is set to 59.9°-60.1°, the relief angle of the blade is set to 28.4°-28.6°, and the metal sharp angle in the range of 0.5mm-1mm of the tip of the blade is set), the sharpness of the blade face is ensured through the rake angle design of the movement direction of the blade, and the friction of the blade is reduced through the relief angle design of the blade; according to the characteristics that the tool head is used by astronauts in a vacuum environment, through the above parameter design, the tool head is ensured to move at a low speed, the tool tip still has processing on the cutting object under the condition of small cutting force, and has the characteristics of high-precision processing.

[0033] In a preferred embodiment of the present application, the rake angle of the blade is set to 60° Figure 4 ), the relief angle of the blade is set to 28.5° Figure 5 ) to form a cutting angle of 31.5°, the strength of the blade is increased under the premise of ensuring the sharpness of the rake face and the small friction of the relief face, the side angle of the blade is set to 25° Figure 6 ) to ensure the sharpness of the tip of the blade and the strength of the tip.

[0034] To remind astronauts that this tool head is dangerous goods and is prohibited to touch, red vacuum pigment is applied on the outside of the tool head, so that astronauts can clearly see the tool head area in the space suit outside the cabin.

[0035] (3) Work flow

[0036] The tool shaft rotates at a rotation speed of 50° / s, the blade is first contacted with the cutting surface by the tip under the action of constant pressure, and then the object is cut by the rake face.

[0037] During the cutting process of the blade, the blade is subjected to F0 cutting resistance, f1 tool shaft rotation resistance and f2 upward component of the blade, wherein when f2=F constant, the cutting resistance and the blade pressure are balanced, and the blade does not feed. With the cutting process of the blade, when f2 decreases, the blade further moves downward under the action of F constant, until f2 increases again to realize f2=F constant.

[0038] Finally, the blade forms a process of gradually autonomous feeding under the action of constant pressure, and finally realizes the cutting of the object.

[0039] The utility model discloses although has disclosed as above with preferable embodiment, but it is not used to limit the utility model, any person skilled in the art without departing from the spirit and range of the utility model can utilize the method and technical content of above disclosure to make possible change and modification to the utility model technical scheme, therefore, all the content without departing from the utility model technical scheme, according to the technical essence of the utility model to the simple modification, equivalent change and modification of above embodiment, all belong to the protection range of the utility model technical scheme.

Claims

1. A low-speed rotating cutter head structure suitable for vacuum environments, comprising a cutter body and cutting edges distributed on the cutter body, characterized in that: The number of the cutting edges is multiple, which are uniformly distributed in the circumferential direction of the cutter body; each cutting edge comprises a rake angle representing the inclination degree of the rake face, a relief angle representing the friction degree of the relief face in the cutting process, a side angle representing the cutting angle in the cutting process, and a cutting tip according to the movement mode of the cutting edge; the side angle is set to 24.9°-25.1°, which ensures that the cutting tip can be self-fed and cut under the action of constant pressure in the condition of low speed of the cutter shaft rotation speed not more than 50° / s in the vacuum environment.

2. The low-speed rotating tool head structure for use in a vacuum environment according to claim 1, characterized by: The side angle is set to 25°.

3. The low speed rotary tool head structure for use in a vacuum environment according to claim 1, wherein: The rake angle of the cutting edge is set to 59.9°-60.1°, which improves the drilling efficiency of the drill bit.

4. The low speed rotary tool head structure for use in a vacuum environment according to claim 3, wherein: The rake angle of the cutting edge is set to 60°.

5. The low speed rotary tool head structure for use in a vacuum environment according to claim 3, wherein: The relief angle of the cutting edge is set to 28.4°-28.6°, which improves the surface finish of the drilling.

6. A low speed rotary tool head structure for use in a vacuum environment according to claim 5, wherein: The relief angle of the cutting edge is set to 28.5°.

7. The low speed rotary tool head structure for use in a vacuum environment according to claim 1, wherein: The cutting tip is a front-end round head with a diameter of 0.5mm-1mm.

8. The low speed rotary tool head structure for use in a vacuum environment according to claim 1, wherein: An inner hexagonal hole is arranged at the bottom of the cutter body.

9. The low speed rotary tool tip structure for use in a vacuum environment of claim 1, wherein: Red vacuum paint is applied to the outer side of the cutter body and the cutting edge.

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