Machining method for tooth surface line contact flat spiral arc tooth trace cylindrical gear based on staggered arrangement of trapezoidal blades

Abstract

The invention discloses a method for processing a tooth surface line contact flat-rotation arc-tooth-trace cylindrical gear based on staggered arrangement of trapezoidal blades, which comprises the following steps: S1, a main blade I and a main blade II are mounted on a cutterhead, so that the position angle difference between the main blade I and the main blade II is # imgabs0 #, and the main blade I, the main blade II and an auxiliary cutter are all arranged on a set spiral line; s2, cutting deep processing is conducted, the gear blank rotates at the angular speed # imgabs 1 # while the cutter head rotates at the angular speed # imgabs 1 #, so that cross-tooth milling is achieved, and after the gear blank rotates by a circle, the gear blank conducts feeding motion in the tooth height direction till cutting of all tooth grooves is completed; s3, tooth surface generating machining is carried out; efficient machining of the cylindrical gear with the tooth surface in linear contact can be achieved, and the technical problem that in the prior art, only point contact can be machined, and the tooth surface in linear contact cannot be achieved is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of cylindrical gear machining, and particularly to a machining method for a face line-contact flat rotary arc-tooth cylindrical gear based on staggered arrangement of trapezoidal blades. Background Art

[0002] Spiral bevel cylindrical gears have more excellent transmission characteristics and stronger face load-bearing capacity. However, due to the need for tooth-by-tooth milling, the machining efficiency is low and high-efficiency milling cannot be achieved, and the face machining quality cannot be guaranteed. The flat spiral tooth cylindrical gear machined by a multi-blade milling disc arranged based on the Archimedean spiral can ensure high-efficiency and high-precision machining. However, the difference in the curvature radius of the concave and convex tooth faces of the machined gear is relatively large, and the theoretical contact form is point contact. After being loaded, elastic deformation occurs, the contact surface is elliptical, and the meshing contact line of the gear pair is mainly distributed in the middle of the tooth face, and line contact of the tooth face cannot be achieved. Summary of the Invention

[0003] The purpose of this part is to outline some aspects of the embodiments of the present invention and briefly introduce some preferred embodiments. Simplifications or omissions may be made in this part, as well as in the abstract and title of the present application, to avoid obscuring the purpose of this part, the abstract, and the title. Such simplifications or omissions shall not be used to limit the scope of the present invention.

[0004] In view of the above and / or existing problems in cylindrical gear machining, the present invention is proposed.

[0005] Therefore, the purpose of the present invention is to provide a machining method for a face line-contact flat rotary arc-tooth cylindrical gear based on staggered arrangement of trapezoidal blades. A main blade one and a main blade two are arranged on the cutter disc. The inner cutting edge of the main blade one mills the convex tooth face of the tooth, and the outer cutting edge of the main blade two mills the concave tooth face of the tooth. It breaks the conventional setting. By adjusting the angular difference of the installation positions of the main blade one and the main blade two on the cutter disc, the rotation radius of the cutting edge can be changed, thereby adjusting the curvature radius of the concave and convex tooth face tooth lines and controlling the crown amount of the flat rotary arc-tooth cylindrical gear.

[0006] To solve the above technical problems, the present invention provides the following technical solution: A machining method for a face line-contact flat rotary arc-tooth cylindrical gear based on staggered arrangement of trapezoidal blades. The machining device used in the machining includes a rotatable cutter disc and a base. A movable Y-axis slide is connected to the base. An X-axis slide that can move is connected to the Y-axis slide. The moving directions of the X-axis slide and the Y-axis slide are perpendicular. A vertically arranged rotating shaft for connecting the blank is rotatably connected to the X-axis slide. The central axis of the cutter disc and the central axis of the rotating shaft are perpendicular to each other. A main blade one and a main blade two are installed on the cutter disc. A number of auxiliary tools are also installed on the cutter disc. The length of the auxiliary tool extending out of the cutter disc is less than the length of the main blade one or the main blade two extending out of the cutter disc. The method includes the following steps.

[0007] S1. Install the primary blade one and the primary blade two on the cutter head, such that the angular difference in position between the primary blade one and the primary blade two is , and the primary blade one, the primary blade two, and the auxiliary tool are all on the set spiral line, and the spiral line equation is , represents the installation radius of the primary blade one, is the position angle of a point on the spiral line, and m represents the module of the gear;

[0008] S2. Perform finish machining. While the cutter head rotates at an angular velocity , the blank rotates at an angular velocity , and it satisfies , where Z is the number of teeth of the face-contact flat turning arc tooth line cylindrical gear, thereby realizing cross-tooth milling. After the blank rotates one circle, the blank makes a feed movement along the tooth height direction until the cutting of all tooth grooves is completed;

[0009] S3. Perform face generation machining.

[0010] As a preferred embodiment of the machining method of the face-contact flat turning arc tooth line cylindrical gear based on the staggered arrangement of trapezoidal blades in the present invention, wherein: the specific steps of step S3 are as follows. When performing face generation machining on the convex tooth face of the gear, the cutter head maintains the original rotational angular velocity , and the feed velocity along the negative direction of the axis becomes zero. At this time, the Y-axis slide starts to perform a linear motion along the positive direction of the axis at a velocity , and the velocity relationship satisfies , where r is the pitch circle radius of the blank. At the same time, the rotational speed of the blank is adjusted to , where is the additional rotational speed applied to the blank, and this angular velocity rotates clockwise along the positive direction of the axis, that is, the face generation of the left tooth face of the gear in the face generation motion is completed; then the blank is returned to the original position along the reverse path, and finally the face generation machining of the right tooth face is performed.

[0011] As a preferred embodiment of the machining method of the face-contact flat turning arc tooth line cylindrical gear based on the staggered arrangement of trapezoidal blades in the present invention, wherein: the tooth line equations of the concave tooth face and the convex tooth face in the face-contact flat turning arc tooth line cylindrical gear are respectively , , represents the rotational radius of the inner cutting edge of the primary blade one and the outer cutting edge of the primary blade two at the pitch circle; m represents the module of the gear, , .

[0012] As a preferred embodiment of the processing method of the flat rotary arc tooth line cylindrical gear with line contact on the tooth surface based on the staggered arrangement of trapezoidal blades in the present invention, wherein: the tool widths of the first main blade, the second main blade and the auxiliary tool are all not greater than .

[0013] As a preferred embodiment of the processing method of the flat rotary arc tooth line cylindrical gear with line contact on the tooth surface based on the staggered arrangement of trapezoidal blades in the present invention, wherein: the generating motion of the concave tooth surface is similar to that of the convex tooth surface. The difference is that the tooth blank is changed to move linearly along the negative direction of the axis at a speed of , and the angular velocity of the rotation of the tooth blank is adjusted to .

[0014] As a preferred embodiment of the processing method of the flat rotary arc tooth line cylindrical gear with line contact on the tooth surface based on the staggered arrangement of trapezoidal blades in the present invention, wherein: both the first main blade and the second main blade are trapezoidal blades. The trapezoidal blade has two cutting edges. The outer cutting edge on the outside of the blade is the outer cutting edge, and the inner cutting edge on the inside is the inner cutting edge. The inner cutting edge of the first main blade mills the convex tooth surface of the tooth blank, and the outer cutting edge of the second main blade mills the concave tooth surface of the tooth blank.

[0015] As a preferred embodiment of the processing method of the flat rotary arc tooth line cylindrical gear with line contact on the tooth surface based on the staggered arrangement of trapezoidal blades in the present invention, wherein: is greater than 120° but not greater than 180°.

[0016] Compared with the prior art, the present invention has the following technical effects: The present invention can be used to process a flat translation spiral arc tooth line cylindrical gear pair with line contact on the tooth surface; only by adjusting the installation radii of the first main blade and the second main blade, the control of the difference in the curvature radii of the concave tooth line and the convex tooth surface can be realized, so that line contact on the tooth surface is achieved when the convex and concave tooth surfaces of the flat rotary arc tooth line cylindrical gear pair are engaged, and the load-bearing capacity and transmission characteristics of the gear pair are improved; the tool widths of all blades at the pitch circle are all not greater than , the heights of the auxiliary tools extending outside the cutter head are all lower than those of the main blades. When the auxiliary tools are processing, they only share the cutting amount and the cutting force and do not affect the formation of the tooth groove, thereby reducing the cutting amount and the cutting force of the first main blade or the second main blade, reducing wear and improving the tooth surface forming accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts. Among them:

[0018] Figure 1This is a schematic structural diagram of the device for machining a cylindric gear with a flat rotary arc tooth line in line contact on the tooth surface in the present invention.

[0019] Figure 2 This is the angular difference of the installation positions of the two main blades on the cutter head in the present invention. Schematic diagram of the layout position at that time.

[0020] Figure 3 In the present invention Figure 2 The middle tool widths are all Schematic cross-sectional view of the main blade.

[0021] Figure 4 This is a schematic diagram of the cutting edge locus of the cylindric gear with a flat rotary arc tooth line in line contact on the tooth surface in the present invention.

[0022] Figure 5 This is a schematic diagram of the generating motion of the left tooth surface in the present invention.

[0023] Figure 6 This is a schematic diagram of the generating motion of the right tooth surface in the present invention.

[0024] Figure 7 This is a schematic diagram of the cylindric gear with a flat rotary arc tooth line in line contact on the tooth surface in the present invention.

[0025] Figure 8 This is a schematic diagram of the development of the pitch circle of the cylindric gear with a flat rotary arc tooth line in line contact on the tooth surface in the present invention.

[0026] Figure 9 This is a schematic diagram of the meshing of the cylindric gear pair with a flat rotary arc tooth line in line contact on the tooth surface in the present invention.

[0027] Figure 10 This is a schematic diagram of the installation height of the blade in the present invention.

[0028] In the figure, 1 is the first main blade, 2 is the blank, 3 is the rotating shaft, 4 is the X-axis slide, 5 is the Y-axis slide, 6 is the base, 7 is the cutter head, 8 is the second main blade, 9 is the tool bar, 10 is the auxiliary tool, and 11 is the spiral line. Detailed implementation manners

[0029] To make the above objects, features and advantages of the present invention more obvious and understandable, the following detailed description of the specific implementation manners of the present invention will be given in conjunction with the accompanying drawings of the specification.

[0030] In the following description, many specific details are set forth in order to fully understand the present invention. However, the present invention can also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0031] Second, the so-called "one embodiment" or "embodiment" herein refers to specific features, structures or characteristics that can be included in at least one implementation manner of the present invention. The phrase "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor is it an individual or alternative embodiment that is mutually exclusive with other embodiments.

[0032] Embodiment: Refer to Figures 1 to 10 , which is the first embodiment of the present invention. This embodiment provides a processing method for a flat rotary arc tooth line cylindrical gear with line contact on the tooth surface, and a flat rotary arc tooth line cylindrical gear with line contact on the tooth surface can be realized by using it.

[0033] A processing method for a flat rotary arc tooth line cylindrical gear with line contact on the tooth surface based on staggered arrangement of trapezoidal blades. The processing device used in the processing includes a rotatable cutter head 7 and a base 6. A Y-axis slide 5 that can move back and forth is connected to the base 6. An X-axis slide 4 that can move left and right is connected to the Y-axis slide 5. A vertically arranged rotating shaft 3 for connecting a blank 2 is rotatably connected to the X-axis slide 4. The central axis of the cutter head 7 and the central axis of the rotating shaft 3 are perpendicular to each other. The structures for realizing the movement of the X-axis slide 4 and the Y-axis slide 5 and the rotation of the cutter head 7 are all prior arts and are not the improvement points of the present invention; A main blade one 1 and a main blade two 8 are installed on the cutter head 7. A number of auxiliary tools 10 are also installed on the cutter head 7. The length of the auxiliary tool 10 extending out of the cutter head 7 is less than the length of the main blade one 1 or the main blade two 8 extending out of the cutter head 7. The lengths of the main blade one 1 and the main blade two 8 extending in front of the cutter head 7 are equal. As Figure 3 shown, it is Figure 2 the cross-sectional schematic diagram of the main blade in . The widths of the main blade one 1, the main blade two 8 and the auxiliary tool 10 . When the auxiliary tool 10 is processing, it only shares the cutting amount and cutting force and does not affect the formation of the tooth groove, so as to reduce the cutting amount and cutting force of the main blade, reduce wear and improve the tooth surface forming accuracy; Both the main blade one 1 and the main blade two 8 are trapezoidal blades. The trapezoidal blade has two cutting edges. The outer cutting edge of the blade is the outer cutting edge, and the inner cutting edge is the inner cutting edge. The inner cutting edge of the main blade one 1 mills the convex tooth surface of the blank 2, and the outer cutting edge of the main blade two 8 mills the concave tooth surface of the blank 2. A number of mounting components for connecting the tool bar 9 are detachably connected to the cutter head 7. The mounting components are prior arts and will not be elaborated in this application. Each blade is connected to the corresponding tool bar 9. The tool bars 9 are arranged on the cutter head 7 in an Archimedean spiral 11; The following steps are included,

[0034] S1. Install the main blade one 1 and the main blade two 8 on the cutter head 7 so that the position angle difference between the main blade one 1 and the main blade two 8 is , Greater than 120° but not greater than 180°, the main blade 1, the main blade 2 8 and the auxiliary tool 10 are all on the set helix 11, and the equation of the helix 11 is ,like Figure 2 As shown, the installation position of the main blade 1 is to the center of the cutter head 7 O D The distance is , is the position angle of a point on the helix 11, m represents the gear module, and the pitch of the blade arrangement helix 11 is the tooth pitch of the gear blank 2;

[0035] S2, such as Figure 1 As shown, deep cutting is performed, and the cutter head 7 moves at an angular velocity While rotating, the gear blank 2 moves at an angular velocity Perform rotational motion and satisfy , Z is the number of teeth of the cylindrical gear with horizontal arc tooth line contact, so as to realize cross-tooth milling. When the gear blank 2 rotates one circle, the gear blank 2 is fed along the tooth height direction until all the tooth grooves are cut;

[0036] S3, perform tooth surface development processing, such as Figure 5 As shown, when the convex tooth surface of the gear is generated, the cutter head 7 maintains the original rotation angular velocity ,along Feedrate in the negative direction of the axis becomes zero, and the Y-axis slide 5 starts to move along The positive direction of the axis is measured at speed Start linear motion, the speed relationship satisfies , r is the pitch circle radius of the gear blank 2, and the rotation speed of the gear blank 2 is adjusted to ,in is the additional rotational speed applied to the gear blank 2, and the angular velocity is along The shaft rotates clockwise in the positive direction, completing the generation of the left tooth surface of the gear in the generation movement; then returns to the positive gear blank 2 in the opposite path, and finally performs the generation process of the concave tooth surface. The generation movement of the right tooth surface is similar to that of the left tooth surface, such as Figure 6 As shown, the difference is that the tooth blank 2 is changed to be along The negative direction of the axis is at speed Perform linear motion, and the angular velocity of the gear blank 2 is adjusted to .

[0037] During the development process, the three-dimensional coordinate system O is established with the cutter head 7 plane D -X D Y D Z D , establish a three-dimensional coordinate system O with the rotation plane of gear blank 2 C -X C YC Z C , the above three-dimensional coordinate system is as Figure 1 shown.

[0038] As Figure 4 shown, it is a set of , When it is , the cutting edge rotation trajectories of the main blade 1 and the main blade 8 can be seen that the convex and concave tooth surfaces are cut by the inner cutting edge of the main blade 1 and the outer cutting edge of the main blade 8 respectively, forming tooth grooves.

[0039] Establish a rectangular coordinate system as Figure 4 . The tooth line equations of the concave tooth surface and the convex tooth surface in the face-contact flat envelope spiral bevel gear processed are respectively , [[ID=Z3]]Taking the rotation center O N of the main blade 1 as the center of the circle, the rotation direction of the gear blank 2 as the X-axis, and the axis direction of the rotation center of the gear blank 2 as the Z-axis, a rectangular coordinate system is established; θ is the independent variable, which is the position angle of any point on the tooth line, that is, the rotation angle of the corresponding blade. When θ is 0 + 2kπ (k is an integer), the blade coincides with the X-axis and cuts to the middle line of the tooth width of the gear blank 2; the rotation center O W of the main blade 8 is O N moves along the X-axis by , represents the rotation radius of the inner cutting edge of the main blade 1 and the outer cutting edge of the main blade 8 at the pitch circle; m represents the module of the gear, [[ID=3S]], ; when the installation position angle difference between the main blade 1 and the main blade 8 on the cutter head 7 is , the difference in the rotation radius of the tooth surface forming cutting edges of the main blade 1 and the main blade 8 at the pitch circle is 0, and the face-contact flat envelope spiral bevel gear can achieve face contact of the tooth surface; the processed face-contact flat envelope spiral bevel gear is as Figure 7 shown.

[0040] As Figure 8 shown, it is the development diagram of the face-contact flat envelope spiral bevel gear at the pitch circle when the installation position angle difference between the main blade 1 and the main blade 8 on the cutter head 7 is . The line segment AC is equal to the line segment DE, that is, the tooth groove widths are equal. As Figure 9 shown, when a pair of face-contact flat envelope spiral bevel gear pairs mesh, they are in face contact of the tooth surface, improving the tooth surface contact characteristics and enhancing the meshing stability and load-carrying capacity of the gear pair. When the installation position angle difference When it is less than 180° (between 120° and 180°), the rotational radius of the tooth surface forming cutting edge of the first main blade 1 at the pitch circle is slightly smaller than that of the tooth surface forming cutting edge of the second main blade 8 at the pitch circle. Then, the curvature radius of the convex tooth surface tooth line is slightly smaller than that of the concave tooth surface tooth line, forming a slightly bulged gear tooth.

[0041] As Figure 10 shown, it is a schematic diagram of the installation height with three blades as an example. The installation heights of the first main blade 1 and the second main blade 8 are respectively , and . The installation height of the auxiliary tool 10 is , and . During the cutting process, the auxiliary tool 10 only removes the surplus material and does not affect the tooth surface formation. This arrangement can reduce the cutting force and cutting amount of the tooth surface forming cutting edges of the first main blade 1 and the second main blade 8, ensure the tooth surface formation accuracy, and improve the cutting finish.

[0042] With reverse thinking, the present invention enables the first main blade 1 with a large installation radius to mill the convex tooth surface, and the second main blade 8 with a small installation radius to mill the concave tooth surface, solving the technical problem in the prior art that a cylindrical gear with a tooth surface line contact flat swing arc tooth line cannot be machined. Combining with the setting of the angle difference between the first main blade 1 and the second main blade 8, the curvature radii of the tooth lines of the convex tooth surface and the concave tooth surface can be adjusted.

[0043] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not restrictive. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered by the scope of the claims of the present invention.

Claims

1. A machining method for a face-line contact flat-spiral arc-tooth cylindrical gear with trapezoidal blades arranged staggeredly. The machining device used in the machining includes a rotatable cutter head and a base. A movable Y-axis slide is connected to the base, and a movable X-axis slide is connected to the Y-axis slide. The moving directions of the X-axis slide and the Y-axis slide are perpendicular to each other. A vertically arranged rotating shaft for connecting a gear blank is rotatably connected to the X-axis slide. The central axis of the cutter head and the central axis of the rotating shaft are perpendicular to each other. It is characterized in that: The main blade one and the main blade two are installed on the cutter head. A number of auxiliary cutters are also installed on the cutter head. The length that the auxiliary cutter extends outside the cutter head is less than the length that the main blade one or the main blade two extends outside the cutter head. It includes the following steps. S1. Install the first main blade and the second main blade on the cutter head, such that the positional angular difference between the first main blade and the second main blade is , and the first main blade, the second main blade and the auxiliary tool are all on the set spiral line, and the spiral line equation is , represents the installation radius of the first main blade, is the position angle of a point on the spiral line, and m represents the module of the gear; S2. Perform finish machining. While the cutter head rotates at an angular velocity , the blank rotates at an angular velocity , and it satisfies , where Z is the number of teeth of the face-contact flat-spiral bevel gear. In this way, cross-tooth milling is achieved. After the blank rotates one circle, the blank makes a feed movement along the tooth height direction until all the tooth grooves are cut; S3. Carry out tooth surface generation machining.

2. The machining method of the face line contact flat rotary arc tooth line cylindrical gear based on the staggered arrangement of trapezoidal blades as claimed in claim 1, wherein: The specific steps of step S3 are as follows: When generating the convex tooth surface of the gear, the cutter head maintains the original rotational angular velocity , along the feed rate in the negative direction of the axis becomes zero. At this time, the Y-axis slide starts to move linearly along the positive direction of the axis at a speed and starts to move linearly. The speed relationship satisfies , where r is the pitch circle radius of the blank. At the same time, the rotational speed of the blank is adjusted to , where is the additional rotational speed applied to the blank. This angular velocity rotates clockwise in the positive direction of the axis, that is, the generation of the convex side tooth surface of the gear in the generating motion is completed; then the blank is returned to the original position along the reverse path, and finally the generation machining of the concave tooth surface is carried out.

3. The machining method of the flat rotary arc tooth line cylindrical gear with line contact on the tooth surface based on the staggered arrangement of trapezoidal blades as claimed in claim 2, wherein: The tooth line equations of the concave tooth surface and the convex tooth surface of the face-contact flat swing circular-arc tooth line cylindrical gear are respectively and , represents the rotation radius of the inner cutting edge of the first main blade and the outer cutting edge of the second main blade at the pitch circle; m represents the module of the gear, , .

4. The machining method of the face line contact flat rotary arc tooth line cylindrical gear based on the staggered arrangement of trapezoidal blades according to any one of claims 1 to 3, characterized in that: The widths of the main blade 1, the main blade 2 and the auxiliary cutting tool are all not greater than .

5. The machining method of the face line contact flat rotary arc tooth line cylindrical gear based on the staggered arrangement of trapezoidal blades as claimed in claim 2, wherein: The generation motion of the concave tooth surface is similar to that of the convex tooth surface. The difference is that the blank is changed to move linearly along the negative direction of the axis at a speed of , and the angular velocity of the blank rotation is adjusted to .

6. The machining method of the face line contact flat swing arc tooth line cylindrical gear based on the staggered arrangement of trapezoidal blades according to claim 2, characterized in that: Both the main blade one and the main blade two are trapezoidal blades. The trapezoidal blade has two cutting edges. The outer cutting edge of the blade is the outer cutting edge, and the inner cutting edge is the inner cutting edge. The inner cutting edge of the main blade one mills the convex tooth surface of the blank, and the outer cutting edge of the main blade two mills the concave tooth surface of the blank.

7. The machining method of the face line contact flat rotary arc tooth line cylindrical gear based on the staggered arrangement of trapezoidal blades as described in any one of claims 1 to 3, 5 or 6, characterized in that: Greater than 120° but not greater than 180°.

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