Straight tooth cycloid tooth cutting tooth cutter and construction method thereof

Abstract

The invention discloses a straight-tooth cycloid tooth cutting cutter and a construction method thereof in the technical field of machining design, the straight-tooth cycloid tooth cutting cutter comprises a cutter body and a plurality of cutter teeth evenly arranged in the circumferential direction of the cutter body, each cutter tooth comprises a rear cutter face, a front cutter face and a cutting edge, and the cutting edge is a conjugate line of the tooth face of a cycloid gear to be machined. The cutting edge is an intersection line of the tooth surface of the cycloidal gear to be machined and the front tool face, the rear tool face is a free-form surface composed of a plurality of cutting edges, and the front tool face is a free-form surface for controlling the cutting front angle of the cutting edge to be constant. According to the straight tooth cycloid tooth cutting cutter, it can be guaranteed that the cutting front angles of the cutting edges of the straight tooth cycloid tooth cutting cutter are consistent, the high machining precision is guaranteed, the good surface quality is guaranteed, and it is guaranteed that the precision is constant.

Description

Technical Field

[0001] The invention belongs to the technical field of mechanical processing design, and in particular is a spur-tooth cycloid-tooth cutting cutter and a construction method thereof. Background Art

[0002] Gears are basic parts that need to be used in many industries. At present, my country's gear industry is large but not strong, with prominent structural contradictions, huge production capacity of low-end gears, insufficient production capacity of high-end gears, and a very large gap in the quality stability and reliability of high-end gear products compared with developed countries. High-end gear products rely heavily on imports, such as involute and arc gears, and even more so for cycloid gears. Scudding technology (known as Scudding or Power Skiving abroad) is a new gear processing technology that has only been truly realized in the 21st century. It has the advantages of high efficiency, high precision, and dry cutting. Unfortunately, although the gear skiving technology has been developed for many years, it has not yet been widely used. One of the important reasons is that there is no qualitative breakthrough in tool design. The cycloid gear skiving cutter currently developed on the market is only a visiting model and cannot be truly put into actual production and processing. Summary of the invention

[0003] In order to solve the problem that the above-mentioned cycloidal tooth cutter is only a viewing model but not actually produced, the purpose of the present invention is to provide a spur tooth cycloidal tooth cutter and a construction method thereof, which can ensure that the cutting front angle of the cutting edge of the spur tooth cycloidal tooth cutter is consistent, thereby ensuring both high processing accuracy and good surface quality, and ensuring constant accuracy.

[0004] In order to achieve the above-mentioned purpose, the technical scheme of the present invention is as follows: a spur cycloid tooth cutting cutter comprises a cutter body and a plurality of cutter teeth evenly arranged along the circumference of the cutter body, the cutter teeth comprising a back cutter face, a front cutter face and a cutting edge, the cutting edge is a conjugate line of the cycloid wheel tooth face to be processed, and the cutting edge is an intersection line of the cycloid wheel tooth face to be processed and the front cutter face, the back cutter face is a free-form surface composed of a plurality of cutting edges, and the front cutter face is a free-form surface for controlling a constant cutting front angle of the cutting edge.

[0005] Furthermore, the blade teeth are straight teeth.

[0006] Further, the cutting front angle of the cutting edge is 5-10°.

[0007] Furthermore, the cycloid wheel tooth surface in contact with the cutting edge is assumed to be the P tooth surface. According to the conjugate principle, a conjugate tooth surface model of the P tooth surface is established. Some points are selected on the conjugate tooth surface of the P tooth surface according to the constraint conditions as the cutting edge profile points. The cutting edge profile points are fitted with a spline curve to obtain a space curve, which is the cutting edge.

[0008] The cutting edge is composed of the left cutting edge and the right cutting edge, and the constraint condition of the left cutting edge shape value point is: the difference between adjacent shape value points in a certain coordinate axis direction is a constant value, and X i+1 Relative to X i The direction of X i+2 Relative to X i+1 The direction is consistent, i = 1, 2, 3...n; the constraint conditions of the right cutting edge value point are: the difference between adjacent value points in a certain coordinate axis direction is a constant value, and Y i+1 Relative to Y i The direction of Y i+2 Relative to Y i+1 The direction is consistent, i = 1, 2, 3...n; X i With Y i The overlap is the focus of the cutting edge.

[0009] Furthermore, the modification coefficient of the conjugate tooth surface of the P tooth surface is changed to obtain several conjugate tooth surfaces of the P tooth surface, and several cutting edges are obtained. The cutting edges are fitted with a curved surface, and the resulting curved surface is the flank surface.

[0010] Furthermore, let the corresponding value point on the cutting edge be U i , where i = 1, 2, 3...n, and establish a tool cutting angle reference plane including a base plane, a cutting plane and an orthogonal plane;

[0011] Let line segment U i K i lies on the intersection of the orthogonal plane and the base plane, and The direction points inward; in the orthogonal plane, through the value point U i Make line segment U i V i ,make Point to the inside of the blade teeth, making the angle V i U i K i Equal to the cutting front angle of the set cutting edge; i V i Perform surface fitting, where i = 1, 2, 3...n, and the obtained surface is called surface S1; V1 and V n Connect them with line segments. i The structure is a filling surface S2, where i=1, 2, 3...n; the surface S1 and the surface S2 together constitute the rake surface.

[0012] The principle and beneficial effects of the basic scheme are: a cycloidal tooth scraping cutter of the present invention has equal rake angles at each point on the cutting edge, so that the surface quality of the cycloidal wheel processing is better, the processing accuracy is higher, and the tooth surface processing accuracy is consistent; for the cycloidal wheel tooth surface, the processing accuracy before and after the tool is sharpened is consistent, that is, constant accuracy; when the cycloidal tooth scraping cutter is used to scrape the cycloidal wheel, the cutting force fluctuates little. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 1 is an axonometric view of a spur-tooth cycloid-tooth cutter in an embodiment of the present invention.

[0014] Figure 2 Schematic diagram of the tooth structure of the cycloid tooth cutting cutter in an embodiment of the present invention.

[0015] Figure 3 Schematic diagram of the cutting edge structure of the cycloid tooth cutter in an embodiment of the present invention.

[0016] Figure 4 Schematic diagram of the flank formation process of the cycloid-toothed cutter in an embodiment of the present invention.

[0017] Figure 5 Schematic diagram of the reference plane of the tool cutting angle of the cycloid tooth cutter in the embodiment of the present invention.

[0018] Figure 6 Schematic diagram of the process of forming the rake face of the cycloid tooth cutter in an embodiment of the present invention. DETAILED DESCRIPTION

[0019] The following is further described in detail through specific implementation methods:

[0020] The reference numerals in the drawings of the specification include: a cutter body 1 , a cutter tooth 2 , a flank surface 201 , a cutting edge 202 , and a rake surface 203 .

[0021] The embodiment is basically as shown in the attached Figure 1-Figure 6 As shown: a spur cycloid tooth cutting cutter, comprising a cutter body 1 and a plurality of cutter teeth 2 evenly arranged along the circumference of the cutter body 1, the cutter teeth 2 comprising a flank 201, a rake 203 and a cutting edge 202, the cutting edge 202 being a conjugate line of the cycloid wheel tooth surface to be processed, and the cutting edge 202 being an intersection line between the cycloid wheel tooth surface to be processed and the rake 203, the flank 201 being a free-form surface composed of a plurality of cutting edges 202, and the rake 203 being a free-form surface for controlling a constant cutting front angle of the cutting edge 202. The cutter teeth 2 are spur teeth, the cutting front angle of the cutting edge 202 is 5-10°, and the cutting edge 202 after re-sharpening is still on the conjugate surface of the cycloid wheel tooth surface to be processed.

[0022] Example 2

[0023] The difference from the above embodiment is that a method for constructing a spur cycloid tooth cutter is that firstly, the cycloid wheel tooth surface in contact with the cutting edge 202 is set as the P tooth surface, and according to the conjugate principle, a conjugate tooth surface model of the P tooth surface is established, and some points are selected on the conjugate tooth surface of the P tooth surface according to the constraint conditions as the cutting edge 202 type value points, and the cutting edge 202 type value points are fitted with a spline curve to obtain a space curve, and this curve is the cutting edge 202;

[0024] Then, the displacement coefficient of the conjugate tooth surface of the P tooth surface is changed to obtain a plurality of conjugate tooth surfaces of the P tooth surface, and a plurality of cutting edges 202 are obtained. The cutting edges 202 are fitted with a curved surface, and the resulting curved surface is the flank surface 201 .

[0025] Finally, let the corresponding profile point on the cutting edge 202 be U i , where i = 1, 2, 3...n, and establish a tool cutting angle reference plane including a base plane, a cutting plane and an orthogonal plane;

[0026] Let line segment U i K i lies on the intersection of the orthogonal plane and the base plane, and The direction points inward; in the orthogonal plane, through the value point U i Make line segment U i V i ,make Point to the inside of the blade teeth, making the angle V i U i K i is equal to the cutting front angle of the cutting edge 202; i V i Perform surface fitting, where i = 1, 2, 3...n, and the obtained surface is called surface S1; V1 and V n Connect them with line segments. i The structure is a filled surface S2 , where i=1, 2, 3 . . . n; the surface S1 and the surface S2 together constitute the rake surface 203 .

[0027] The specific implementation process is as follows:

[0028] Taking the cycloid wheel in a certain reducer as an example, the design process of the cycloid tooth cutting cutter is explained. The main parameters of the cycloid wheel are shown in Table 1-1, and the tool parameters are set according to the cycloid wheel parameters as shown in Table 1-2.

[0029] Table 1-1 Cycloidal wheel parameters

[0030]

[0031] Table 1-2 Parameters of cycloid wheel cutter

[0032]

[0033] The cycloid tooth cutting cutter construction method of the present invention comprises:

[0034] 1. Cutting edge construction method:

[0035] Assume that the tooth surface of the cycloid wheel in contact with the cutting edge 1 is tooth surface A. According to the conjugate principle, a conjugate tooth surface model of the cycloid wheel tooth surface A is established. On the conjugate tooth surface of the cycloid wheel tooth surface A, some points are selected as cutting edge value points according to the constraint conditions. Let X i is the shape value point on the conjugate tooth surface of the cycloid wheel A, i = 1, 2, 3...n, these shape value points X i A space curve is obtained by fitting the spline curve, and this curve is the cutting edge 202. The cutting edge 202 is composed of a left cutting edge and a right cutting edge.

[0036] Among them, the constraint conditions of the left cutting edge value point are: the difference between adjacent value points in a certain coordinate axis direction is a constant value, and X i+1 Relative to X i The direction of X i+2 Relative to X i+1 The direction is consistent, i = 1, 2, 3...n. The constraint conditions of the right cutting edge value point are: the difference between adjacent value points in a certain coordinate axis direction is a constant value, and Y i+1 Relative to Y i The direction of Y i+2 Relative to Y i+1 The direction is consistent, i = 1, 2, 3...n. X i With Y i Overlap, and both are the focus of the cutting edge 202.

[0037] 2. Construction method of the back face:

[0038] By changing the modification coefficient of the conjugate tooth surface of the cycloid wheel A tooth surface, a series of conjugate tooth surfaces of the cycloid wheel A tooth surface are obtained. According to the above constraints, the cutting edge 202 type value points are selected to obtain a series of cutting edges 202. These cutting edges 202 are fitted with a curved surface, and the resulting curved surface is the back cutting surface 201.

[0039] 3. Construction method of the front cutting edge:

[0040] Corresponding to the profile point U on the cutting edge i , i = 1, 2, 3...n, establish the tool cutting angle reference plane including the base plane, cutting plane and orthogonal plane; set the line segment U i K i lies on the intersection of the orthogonal plane and the base plane, and The direction points inward; in the orthogonal plane, through the value point U i Make line segment Ui V i ,make Point to the inside of the blade teeth, making the angle V i U i K i is equal to the cutting front angle of the cutting edge 202; i V i (i=1, 2, 3...n) to do surface fitting, and the obtained surface is called surface S1; V1 and V n Connect them with line segments. i (i=1, 2, 3 . . . n) is constructed as a filling surface S2; the curved surface S1 and the curved surface S2 together constitute the rake surface 203.

[0041] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0042] The above is only an embodiment of the present invention. The common sense such as the known specific structure and characteristics in the scheme is not described in detail here. The ordinary technicians in the relevant field know all the common technical knowledge in the technical field of the invention before the application date or priority date, can obtain all the existing technologies in the field, and have the ability to apply the conventional experimental means before that date. The ordinary technicians in the relevant field can improve and implement this scheme in combination with their own abilities under the enlightenment given by this application. Some typical known structures or known methods should not become obstacles for ordinary technicians in the relevant field to implement this application. It should be pointed out that for those skilled in the art, without departing from the structure of the present invention, several deformations and improvements can be made, which should also be regarded as the protection scope of the present invention, which will not affect the effect of the implementation of the present invention and the practicality of the patent. The protection scope required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A spur-tooth cycloid-toothed cutter, characterized in that: It includes a cutter body and a number of cutter teeth evenly arranged along the circumference of the cutter body. The cutter teeth include a flank face, a rake face and a cutting edge. The cutting edge is a conjugate line of the cycloid wheel tooth surface to be processed, and the cutting edge is an intersection line between the cycloid wheel tooth surface to be processed and the rake face. The flank face is a free-form surface composed of multiple cutting edges, and the rake face is a free-form surface that controls the cutting front angle of the cutting edge to be constant.

2. The spur-tooth cycloid-toothed cutter according to claim 1, characterized in that: The teeth are straight.

3. The spur-tooth cycloid-toothed cutter according to claim 2, characterized in that: The cutting edge has a cutting rake angle of 5-10°.

4. A method for constructing a spur-tooth cycloid-toothed cutter, characterized in that: Assume that the cycloidal wheel tooth surface in contact with the cutting edge is the P tooth surface. According to the conjugate principle, a conjugate tooth surface model of the P tooth surface is established. Some points are selected on the conjugate tooth surface of the P tooth surface according to the constraint conditions as the cutting edge shape value points. The cutting edge shape value points are fitted with a spline curve to obtain a space curve, which is the cutting edge. The cutting edge is composed of the left cutting edge and the right cutting edge, and the constraint condition of the left cutting edge shape value point is: the difference between adjacent shape value points in a certain coordinate axis direction is a constant value, and X i+1 Relative to X i The direction of X i+2 Relative to X i+1 The direction is consistent, i = 1, 2, 3...n; the constraint conditions of the right cutting edge value point are: the difference between adjacent value points in a certain coordinate axis direction is a constant value, and Y i+1 Relative to Y i The direction of Y i+2 Relative to Y i+1 The direction is consistent, i = 1, 2, 3...n; X i With Y i The overlap is the focus of the cutting edge.

5. The method for constructing a spur-tooth cycloid-toothed cutter according to claim 4, characterized in that: By changing the displacement coefficient of the conjugate tooth surface of the P tooth surface, a number of conjugate tooth surfaces of the P tooth surface are obtained, and a number of cutting edges are obtained. The cutting edges are fitted with a curved surface, and the resulting curved surface is the back tool surface.

6. The method for constructing a spur-tooth cycloid-toothed cutter according to claim 5, characterized in that: Let the corresponding point on the cutting edge be U i , where i = 1, 2, 3...n, and establish a tool cutting angle reference plane including a base plane, a cutting plane and an orthogonal plane; Let line segment U i K i lies on the intersection of the orthogonal plane and the base plane, and The direction points inward; in the orthogonal plane, through the value point U i Make line segment U i V i ,make Point to the inside of the blade, making the angle V i U i K i Equal to the cutting front angle of the set cutting edge; i V i Perform surface fitting, where i = 1, 2, 3...n, and the obtained surface is called surface S1; V1 and V n Connect them with line segments, and V i The structure is a filling surface S2, where i=1, 2, 3...n; the surface S1 and the surface S2 together constitute the rake surface.

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