阅读说明：本技术 一种指状刀具制造正交直齿面齿轮的加工方法 (Processing method for manufacturing orthogonal straight-tooth face gear by using finger-shaped cutter ) 是由 彭先龙 侯艳艳 江晓瑜 于 2020-04-07 设计创作，主要内容包括：本发明公开了一种指状刀具制造正交直齿面齿轮的加工方法,加工方法包括设计指状刀具、选用数控机床、设定指状刀具运动规律和编写数控程序等步骤。指状刀具的刀体锥面、刀柄锥面与柱面的产形线均为直线,刀具结构简单,且刀体锥面与被加工的正交直齿面齿轮的齿面为线接触,加工效率高。数控机床包含三个平移运动数控轴、两个旋转运动数控和一个自由旋转轴,齿面切削、磨削过程中三个平移运动数控轴与其中的一个旋转运动数控轴联动,正交直齿面齿轮工件保持静止,另一旋转运动数控轴驱动工件做分度运动。本发明不仅可用于切齿加工,还可用于磨齿加工,并能够对齿高、齿宽方向进行齿面修形。(The invention discloses a processing method for manufacturing an orthogonal straight-tooth face gear by using a finger-shaped cutter. The shape generating lines of the conical surface of the cutter body, the conical surface of the cutter handle and the cylindrical surface of the finger-shaped cutter are all straight lines, the structure of the cutter is simple, the conical surface of the cutter body is in line contact with the tooth surface of the processed orthogonal straight tooth surface, and the processing efficiency is high. The numerical control machine tool comprises three translational motion numerical control shafts, two rotational motion numerical control shafts and a free rotating shaft, wherein the three translational motion numerical control shafts are linked with one rotational motion numerical control shaft in the tooth surface cutting and grinding processes, the orthogonal straight tooth surface gear workpiece is kept static, and the other rotational motion numerical control shaft drives the workpiece to do indexing motion. The invention can be used for not only cutting teeth but also grinding teeth, and can carry out tooth surface modification in the tooth height and tooth width directions.)

1. A processing method for manufacturing an orthogonal straight-tooth face gear by using a finger-shaped cutter is characterized by comprising the following steps:

1) designing a finger-shaped cutter (1);

2) selecting a numerical control machine tool;

3) setting the motion rule of the finger-shaped cutter (1);

4) and (5) writing a numerical control program.

2. The method of manufacturing orthogonal spur face gears with a finger cutter as set forth in claim 1, wherein: the design of the finger cutter (1) comprises the following steps:

① creating a rectangular coordinate system S of the finger-like tool (1)_m(x_my_mz_mO_m) Wherein the coordinate axis z_mCoincides with the axis of the finger cutter (1);

② in the coordinate plane x_mO_mz_mA cutter body conical surface shape generating line (13) is determined on the upper part and is along the coordinate axis z_mNegative direction metric curve starting point (131) to coordinate axis x_mIs a distance L_mThe distance from the midpoint (132) of the generating line to the starting point is u₀The center point (132) of the shape-generating line to the coordinate axis z_mIs 0.25 pi m, m is the module of the gear, the distance from any point on the generating line to the middle point is u, and the included angle between the generating line (13) of the conical surface of the cutter body and the plumb line is a_mAnd u is₀＝1.25m/cosα_m；

③ determined by the following calculation formula α_m：

acos[r_bsN₂/(N_sL₁)]≥α_m≥0；

Wherein r is_bs、N_sRespectively the base radius and the number of teeth, N, of the imaginary involute cylindrical gear₂、L₁The number of teeth and the inner diameter of the orthogonal straight tooth face gear (2) are respectively α_mWhen 0rad, the finger cutter (1) is also called a stick cutter;

④ is formed by making the conical surface of the cutter body (13) form a line around the coordinate axis z_mRotating a circle to obtain a conical cutter body which is divided into a cutting cutter and a grinding cutter, when the conical cutter body is used as the cutting cutter, 4-8 chip grooves are uniformly formed on the circumference of the conical cutter body, and the main cutting edge is positioned on an axial plane x_mO_my_mThe projections are distributed along the radial direction, and when the conical grinding cutter is used as a grinding cutter, the conical cutter body is covered with abrasive materials.

Fifthly, according to the steps from the first step to the fourth step, the calculation formula of the cutter body conical surface of the finger-shaped cutter (1) is as follows:

φ_mis a conical shape generating line (13) of the cutter body around a coordinate axis z_mThe angle of rotation, the structure on the big end of the conical cutter body is a conical cutter handle (12) fixedly connected with the conical cutter body, and the structure on the big end of the conical cutter handle (12) is a cylindrical cutter handle (11) fixedly connected with the conical cutter handle (12).

3. The method of manufacturing orthogonal spur gears with a finger cutter as set forth in claim 2, wherein: the conical surface of the conical surface tool holder (12) of the finger-shaped tool (1) and the shape generating line of the cylindrical surface tool holder (11) are both straight lines, and the tool body conical surface shape generating line (13) of the finger-shaped tool (1) is changed into a parabola or a hyperbolic curve or a spline curve, so that the finger-shaped tool is suitable for modifying the tooth surface of the orthogonal straight tooth surface gear (2) in the tooth height direction.

4. The method of manufacturing orthogonal spur face gears with a finger cutter as set forth in claim 1, wherein: the selected numerical control machine comprises five numerical control shafts and a free rotating shaft, wherein three translation motion numerical control shafts N which are vertical to each other are arranged in the five numerical control shafts_x、N_y、N_zWith two mutually perpendicular numerically controlled axes of rotational movement N_A、N_BThe orthogonal straight tooth face gear (2) workpiece is arranged on a rotary motion numerical control shaft N_AUpper, translational motion numerical control shaft N_x、N_y、N_zNumerical control shaft N for driving rotary motion_BThe numerical control shaft N translates in three spatial directions which are mutually vertical and rotates_BIs perpendicular to the free rotating shaft and drives the free rotating shaft to rotate around a numerical control shaft N_BThe finger-shaped cutters (1) are coaxially arranged on a free rotating shaft, and the free rotating shaft drives the finger-shaped cutters (1) to rotate around the axis of the free rotating shaft to perform cutting motion.

5. The method of manufacturing orthogonal spur face gears with a finger cutter as set forth in claim 1, wherein: the setting of the motion rule of the finger-shaped cutter (1) comprises the following steps:

① static rectangular coordinate system S for setting orthogonal straight tooth face gear (2) workpiece₂(x₂y₂z₂O₂) Wherein the coordinate axis z₂The axis of the workpiece is superposed with the axis of the orthogonal straight tooth face gear (2);

② an auxiliary motion rectangular coordinate system S is set_q(x_qy_qz_qO_q) And S is_qRelative to S₂The following relationship is satisfied: x is the number of_q//x₂、y_q//y₂、z_q//z₂，S_qOrigin of coordinates O_qRelative to S₂Origin of coordinates O₂In the coordinate axis x₂、y₂、z₂The displacements in the directions are X, Y, Z respectively, and the calculation formulas are expressed as:

C_x＝-0.25πmcosα_m-(u₀cosα_m+L_m)sinα_m，

C_y＝-0.25πmsinα_m+(u₀cosα_m+L_m)cosα_m，

θ₀＝0.5π/N_s-tanα+α，

wherein a is the pressure angle of the gear;

③ let the finger-like tool (1) coordinate with a rectangular system S_mAt S_qMiddle rotation, and the following relation is satisfied: origin of coordinates O_q、O_mCoincident, coordinate axes y_q、y_mCoincidence, i.e. S_mWinding y in Sq_qRotation at an angle of psi_m。

6. The method of manufacturing orthogonal spur face gears with a finger cutter as set forth in claim 1, wherein: the writing of the numerical control program comprises the following steps:

1) according to the motion rule of the finger-shaped cutter (1), the cutter body conical surface S of the finger-shaped cutter (1) can be obtained₂The calculation formula of the cone family is as follows:

2) establishing the envelope condition of the cone family of the cutter body, and solving the small inner diameter L of the envelope curved surface of the cone family₁And maximum outer diameter L₂Corresponding corner psi_minAnd psi_mout；

3) Assuming that the position constants of all numerical control shafts relative to the origin of the machine tool are 0, writing a numerical control program for manufacturing the orthogonal straight-tooth face gear (2) by the finger-shaped cutter (1) according to the following steps:

the method comprises the following steps: indexing procedure for the finger cutter (1) to make orthogonal spur face gears (2):

N_Ai＝(i-1)·360°/(N₂-1) i＝1，2，3，…，N₂；

secondly, the step of: the finger-shaped cutter (1) makes the feeding program of the orthogonal straight face gear (2) in the tooth height direction:

Feed_j＝2.25·m-j·2.25·m/J j＝1，2，3，…，J，

wherein J is a positive integer greater than 1 in the rough cutting, semi-finish cutting, rough grinding and semi-finish grinding processing technologies, and J is 1:

③: a spread angle procedure for manufacturing orthogonal straight face gears (2) with finger cutters (1):

N_Bk＝ψ_mk＝ψ_min+(k-1)·(ψ_mout-ψ_min)/(K-1) k＝1，2，3，…，K，

wherein K is a positive integer between 15 and 40 in the rough cutting, semi-finish cutting, rough grinding and semi-finish grinding processing technology, and K is a positive integer between 40 and 90 in the finish cutting and finish grinding processing technology;

fourthly, the method comprises the following steps: the digital control shaft displacement program of the translational motion of the finger-shaped cutter (1) for manufacturing the orthogonal straight-tooth face gear (2) comprises the following steps:

and compiling a numerical control program according to the steps, inputting the numerical control program into a numerical control machine control computer, installing a finger-shaped cutter (1) and an orthogonal straight-tooth face gear (2) workpiece, and further cutting or grinding the orthogonal straight-tooth face gear (2).

7. The method of manufacturing orthogonal spur face gears with a finger cutter as set forth in claim 5, wherein: on a translational motion numerical control shaft N_zThe motion law represented by a parabola, a hyperbola and a spline curve is superposed on the gear surface, and the gear surface shaping method is suitable for shaping the gear surface of the gear (2) with the orthogonal straight gear surface in the tooth width direction.

8. The machining method for manufacturing an orthogonal straight-toothed face gear by using the finger cutter as set forth in any one of claims 1 to 7, wherein: firstly, the finger-shaped cutter (1) carries out tooth-by-tooth processing on the right side tooth surface of the orthogonal straight tooth surface gear (2), and after the right side tooth surfaces of all gear teeth are processed, the numerical control shaft N is in translational motion_yAnd changing the motion direction, and processing the left side tooth surface tooth by tooth.

9. The method of manufacturing orthogonal spur face gears with a finger cutter as set forth in claim 8, wherein: the cutter body conical surface of the finger-shaped cutter (1) and the tooth surface to be processed of the orthogonal straight-tooth face gear (2) are in line contact at any moment, and the processing method is called as the forming processing method of the orthogonal straight-tooth face gear (2).

10. The method of manufacturing orthogonal spur face gears with a finger cutter as set forth in claim 9, wherein: the orthogonal straight-tooth face gear (2) only needs to do indexing movement, and the orthogonal straight-tooth face gear (2) keeps static when the finger-shaped cutter (1) cuts and grinds any tooth side of any gear tooth.

Technical Field

The invention relates to the field of gear manufacturing, in particular to a processing method for manufacturing an orthogonal straight-tooth face gear by using a finger-shaped cutter.

Background

The surface gear transmission is a transmission mechanism with an involute cylindrical gear and a bevel gear which are meshed, and the surface gear transmission is mainly applied to a helicopter power split speed reducer, an automobile differential mechanism and the like, and a transmission system with high requirements on transmission performance such as multi-input multi-output and the like. The processing of the external gear is mainly based on the simulation of the meshing process of the face gear and the involute cylindrical gear, and because the production line of the worm cutter for hobbing and grinding is the involute of the cylindrical gear, the cutter has poor universality, the structure is complex, the cutter is inconvenient to manufacture and repair, and the face gear needs to be processed on a complex machine tool. China always tracks and continues to use foreign machining methods, and although theoretical and experimental research progresses obviously, the cost of tools and the cost of machine tools are always high.

The existing face gear processing method is mainly divided into two types according to the curved surface contact characteristics: the first type is a line contact processing method, such as a traditional gear shaping processing method of face gears (F.L. Litvin, Handbook on face gear drivers with an application input, 2000, NASA/CR-2000-; another line contact machining method is that gritson proposed uses a plane or a cutter with a certain taper to machine a face gear (US20120099939a1, CN103264198A), and based on the control of the cutter, a virtual involute generating wheel is formed in the machining process, so as to cut the face gear. The second type is a point contact processing method, such as a worm tool (US006146253A) using a cylindrical gear involute as a shape generating line, although the tool has the problems of continuous indexing and high processing efficiency, the tool has poor universality, complex structure, inconvenient manufacturing and trimming, and the like; the other point contact processing method is a disk (CN103530458A, CN106238830A) and a disk-shaped cutter which take a cylindrical gear involute as a shape generating line, and the processing efficiency is extremely low due to single tooth indexing and point contact.

Therefore, it is necessary to provide an efficient and high-precision face gear line contact processing method, which can only cut a soft tooth surface or has a large tooth surface deviation, and which has problems of a point contact processing method such as a complicated tool and a low processing efficiency.

Disclosure of Invention

The invention aims to: provided is a machining method which can be used for both gear cutting and gear grinding and can perform tooth surface modification in the tooth height and tooth width directions.

The technical scheme adopted by the invention is as follows:

a processing method for manufacturing an orthogonal straight-tooth face gear by using a finger-shaped cutter comprises the following steps:

1) designing a finger-shaped cutter;

2) selecting a numerical control machine tool;

3) setting a motion rule of the finger-shaped cutter;

4) and (5) writing a numerical control program.

As a preferred mode, designing the finger cutter comprises the steps of:

① creating a Cartesian coordinate System S for the finger cutter_m(x_my_mz_mO_m) Wherein the coordinate axis z_mCoinciding with the axis of the finger cutter;

② in the coordinate plane x_mO_mz_mA conical surface shape-generating line of the cutter body is determined on the upper part and is along the coordinate axis z_mNegative power production shape line starting point to coordinate axis x_mIs a distance L_mThe distance from the midpoint of the product line to the starting point is u₀From the midpoint of the shape-generating line to the coordinate axis z_mIs 0.25 pi m, m is the module of the gear, the distance from any point on the generating line to the middle point is u, and the included angle between the generating line of the conical surface of the cutter body and the plumb line is a_mAnd u is₀＝1.25m/cosa_m；

③ determined by the following calculation formula α_m：

acos[r_bsN₂/(N_sL₁)]≥α_m≥0；

Wherein r is_bs、N_sRespectively the base radius and the number of teeth, N, of the imaginary involute cylindrical gear₂、L₁The number of teeth of each gear being orthogonal straight toothed surfacesAnd an inner diameter when a_mWhen 0rad, the finger cutter is also called a stick cutter;

④ the cone of the cutter body is shaped around the coordinate axis z_mRotating a circle to obtain a conical cutter body which is divided into a cutting cutter and a grinding cutter, when the conical cutter body is used as the cutting cutter, 4-8 chip grooves are uniformly formed on the circumference of the conical cutter body, and the main cutting edge is positioned on an axial plane x_mO_my_mThe projections are distributed along the radial direction, and when the conical grinding cutter is used as a grinding cutter, the conical cutter body is covered with abrasive materials.

Fifthly, according to the steps from the first step to the fourth step, the calculation formula of the cutter body conical surface of the finger-shaped cutter is as follows:

φ_mis a line winding coordinate axis z of the conical surface of the cutter body_mThe structure above the large end of the conical cutter handle is a conical cutter handle fixedly connected with the conical cutter body, and the structure above the large end of the conical cutter handle is a cylindrical cutter handle fixedly connected with the conical cutter handle.

Preferably, the conical surface of the conical surface tool holder and the profile generating line of the cylindrical surface tool holder of the finger-shaped tool are both straight lines, and the modification of the tooth height direction of the tooth surface of the gear with a straight orthogonal tooth surface is suitably performed by replacing the conical surface profile generating line of the tool body of the finger-shaped tool with a parabolic curve or a hyperbolic curve or a spline curve.

As a preferred mode, the selected numerical control machine tool comprises five numerical control shafts and a free rotating shaft, wherein three mutually vertical translational motion numerical control shafts N are arranged in the five numerical control shafts_x、N_y、N_zWith two mutually perpendicular numerically controlled axes of rotational movement N_A、N_BIn which orthogonal straight-tooth face gear workpiece is mounted on rotary motion numerical control shaft N_AUpper, translational motion numerical control shaft N_x、N_y、N_zNumerical control shaft N for driving rotary motion_BThe numerical control shaft N translates in three spatial directions which are mutually vertical and rotates_BIs perpendicular to the free rotating shaft and drives the free rotating shaft to rotate around a numerical control shaft N_BThe finger-shaped cutters are coaxially arrangedOn the free rotating shaft, the free rotating shaft drives the finger-shaped cutter to rotate around the axis of the free rotating shaft to perform cutting motion.

As a preferred mode, the setting of the motion law of the finger-shaped cutter comprises the following steps:

① static rectangular coordinate system S for setting orthogonal straight-tooth face gear workpiece₂(x₂y₂z₂O₂) Wherein the coordinate axis z₂The axis of the workpiece is overlapped with the axis of the orthogonal straight tooth face gear workpiece;

② an auxiliary motion rectangular coordinate system S is set_q(x_qy_qz_qO_q) And S is_qRelative to S₂The following relationship is satisfied: x is the number of_q∥x₂、y_q∥y₂、z_q∥z₂，S_qOrigin of coordinates O_qRelative to S₂Origin of coordinates O₂In the coordinate axis x₂、y₂、z₂The displacements in the directions are X, Y, Z respectively, and the calculation formulas are expressed as:

C_x＝-0.25πmcosα_m-(u₀cosα_m+L_m)sinα_m，

C_y＝-0.25πmsinα_m+(u₀cosα_m+L_m)cosα_m，

θ₀＝0.5π/N_s-tanα+α，

wherein a is the pressure angle of the gear;

③ order the rectangular coordinate system S of finger-like tool_mAt S_qMiddle rotation, and the following relation is satisfied: origin of coordinates O_q、O_mCoincident, coordinate axes y_q、y_mCoincidence, i.e. S_mAt S_qMiddle winding y_qRotation at an angle of psi_m。

6. The method of manufacturing orthogonal spur face gears with a finger cutter as set forth in claim 1, wherein: the numerical control program writing method comprises the following steps:

1) according to the motion rule of the finger-shaped cutter, the conical surface S of the cutter body of the finger-shaped cutter can be obtained₂The calculation formula of the cone family is as follows:

2) establishing the envelope condition of the cone family of the cutter body, and solving the small inner diameter L of the envelope curved surface of the cone family₁And maximum outer diameter L₂Corresponding corner psi_minAnd psi_mout；

3) Assuming that the position constants of the numerical control shafts relative to the origin of the machine tool are all 0, writing a numerical control program for manufacturing the orthogonal straight-tooth face gear by the finger-shaped cutter according to the following steps:

the method comprises the following steps: indexing procedure for finger cutters to make orthogonal spur face gears:

N_Ai＝(i-1)·360°/(N₂-1)i＝1，2，3，…，N₂；

secondly, the step of: feed program of finger cutter for manufacturing orthogonal straight face gear in tooth height direction:

Feed_j＝2.25·m-j·2.25·m/J j＝1，2，3，…，J，

wherein J is a positive integer greater than 1 in the rough cutting, semi-finish cutting, rough grinding and semi-finish grinding processing technologies, and 1 is taken from J in the finish cutting and finish grinding processing technologies;

③: angular spread procedure for finger cutters to make orthogonal straight face gears:

N_Bk＝ψ_mk＝ψ_min+(k-1)·(ψ_mout-ψ_min)/(K-1)k＝1，2，3，…，K，

wherein K is a positive integer between 15 and 40 in the rough cutting, semi-finish cutting, rough grinding and semi-finish grinding processing technology, and K is a positive integer between 40 and 90 in the finish cutting and finish grinding processing technology;

fourthly, the method comprises the following steps: the digital control shaft displacement program of the translational motion of the finger-shaped cutter for manufacturing the orthogonal straight tooth face gear:

preferably, a numerical control program is written according to the steps and input into a numerical control machine control computer, the finger-shaped cutter and the orthogonal straight-tooth face gear workpiece are installed, and then the orthogonal straight-tooth face gear is cut or ground.

Preferably, N is on a numerical control axis of translational movement_zThe motion rules represented by parabola, hyperbola and spline curve are superimposed on the gear tooth surface of the gear, and the gear tooth surface shaping device is suitable for shaping the gear tooth surface of the gear with the orthogonal straight tooth surface in the tooth width direction.

As a preferred mode, firstly, the finger-shaped cutter carries out tooth-by-tooth processing on the right side tooth surface of the orthogonal straight tooth surface gear, and after the right side tooth surfaces of all the gear teeth are processed, the translational motion numerical control shaft N carries out translational motion_yAnd changing the motion direction, and processing the left side tooth surface tooth by tooth.

Preferably, the body conical surface of the finger cutter and the tooth surface to be machined of the orthogonal straight-tooth face gear are in line contact at any instant, and the machining method is called a forming machining method of the orthogonal straight-tooth face gear.

Preferably, the orthogonal spur face gear is only required to perform indexing motion, and the orthogonal spur face gear remains stationary while the finger cutter is cutting and grinding any flank of any tooth.

In summary, due to the adoption of the technical scheme, the invention has the beneficial effects that:

1. in the invention, the shape generating line of the conical surface of the finger-shaped cutter body is a straight line, thereby avoiding involute curves and simplifying the manufacture and the trimming of the conical surface of the cutter body.

2. In the invention, the conical surface of the cutter body of the finger-shaped cutter is in line contact with the tooth surface of the processed orthogonal straight tooth surface gear, so that the traditional point contact is replaced, and the processing efficiency can be greatly improved;

3. the invention can process the orthogonal straight-tooth face gear on the existing 5-axis numerical control machine tool without developing a complex special machine tool.

4. The finger-shaped cutter arranges the cutter body conical surface shaping line as a linear group of orthogonal straight tooth face gear tooth surfaces according to the rule of the invention, can be used for cutting and grinding face gears, and ensures the tooth surface precision, compared with the Gleason plane cutter processing method, the tooth surface deviation of the face gear with the modulus of 6.35 and the tooth number of 160 is reduced from more than 1000 mu m to less than 12 mu m.

Drawings

FIG. 1 is a schematic view of a finger cutter according to the present invention;

FIG. 2 is a schematic view of the coordinate system of FIG. 1;

FIG. 3 is a schematic diagram of a coordinate system and its relative motion relationship for a finger cutter machining orthogonal straight face gears;

FIG. 4 is a schematic view of a finger cutter producing a machined simulated tooth flank of an orthogonal spur gear and its relationship to a gear shaping machined simulated tooth flank;

the labels in the figure are: 1 finger-shaped cutter, 11 cylindrical surface cutter handles, 12 conical surface cutter handles, 13 cutter body conical surface shape-generating lines, 131 shape-generating line starting points, 132 shape-generating line middle points and 2 orthogonal straight-tooth-surface gears.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.