A special-shaped tooth curved rake face tooth-scratching cutter and its design and shaping method

Abstract

The present invention discloses a tooth cutter with a curved front blade surface for special-shaped gears and a design and shaping method thereof in the field of tooth cutter processing. The tool comprises a tool body and a plurality of teeth arranged circumferentially along the outer edge of the tool body; the teeth comprise a cutting edge, a front blade surface and a back blade surface; the cutting edge is a profile point selected by a conjugate surface of the tooth surface of a special-shaped gear according to a constraint condition, and is obtained by fitting the profile point through a fitting curve; the back blade surface is a free-form surface composed of a series of cutting edges obtained by intersection; the front blade surface is a free-form surface for controlling a constant cutting front angle of the cutting edge; the present invention also discloses a design and shaping method for the tooth cutter with a curved front blade surface for special-shaped gears, so that the curved front blade surface of the special-shaped gears is consistent with the cutting front angle of the cutting edge, thereby maintaining the stability of the tooth cutter during cutting to improve the surface quality and enhance the processing accuracy.

Description

Technical Field

[0001] The invention belongs to the field of gear cutting tool processing, in particular to a gear cutting tool with a special-shaped tooth and a curved front cutting surface and a design and shaping method thereof. Background Art

[0002] With the deepening of the theoretical research on gear cutting and the continuous promotion of gear cutting machines, the use of gear cutting technology has become the future trend of gear industry processing. At present, the design theory and method of gear cutting tools are becoming more and more mature, but most of the tool design theories and methods are aimed at involute gear cutting cutters, and the research on tool design of special-shaped gear cutting cutters is blank. However, in actual engineering applications, the demand for special-shaped gears is relatively large. Therefore, the present invention provides a design and modeling method for a special-shaped gear curved front cutting edge gear cutting cutter. Summary of the invention

[0003] The purpose of the present invention is to provide a tooth cutter with a special-shaped tooth and a curved front blade surface and a design and shaping method thereof, so that the cutting front angle of the special-shaped tooth and the curved front blade surface are consistent with the cutting edge, the stability of the tooth cutter during the cutting process is maintained to improve the surface quality and enhance the processing accuracy.

[0004] In order to achieve the above object, the technical solution of the present invention is as follows:

[0005] On the one hand, a tooth-cutting cutter with a curved rake face of a special-shaped tooth type is provided, comprising a cutter body and a plurality of cutter teeth arranged circumferentially along the outer edge of the cutter body;

[0006] The cutting teeth include cutting edge, front cutting face and back cutting face; the cutting edge is the shape value point selected by the conjugate surface of the tooth surface of the special-shaped gear according to the constraint conditions, and is obtained by fitting the shape value point by fitting the curve; the back cutting face is a free-form surface composed of a series of cutting edges obtained by intersection; the front cutting face is a free-form surface that controls the constant cutting front angle of the cutting edge (the free-form surface is constructed in the UG10.0 modeling module through the surface modeling function).

[0007] Furthermore, the blade teeth are straight teeth or helical teeth.

[0008] Further, the cutting front angle of the cutting edge is 5-10°.

[0009] On the other hand, a design and shaping method for the above-mentioned tooth-shaped curved rake face tooth-cutting cutter is provided, comprising the following steps:

[0010] Step 1: Establish a conjugate tooth surface of the tooth surface to be processed according to the processing parameters and the workpiece parameters, select some points on the conjugate tooth surface as cutting edge value points according to the constraint conditions, and fit the cutting edge value points with a spline curve to obtain a spatial curve to form a cutting edge;

[0011] Step 2, establishing a rake face, based on the plurality of cutting edges formed in step 1, forming a curved surface in a constant direction of the cutting rake angle of the cutting edge to establish the rake face;

[0012] Step 3: Establish the back face of the cutting tool. Based on the several cutting edges formed in step 1, the cutting edges are intersected to obtain a free-form surface, and the surface modeling is constructed.

[0013] Furthermore, in steps one to three, the tooth surface of the special-shaped tooth in contact with the cutting edge is assumed to be the P tooth surface, and a conjugate tooth surface model of the P tooth surface is established according to the conjugate principle; the displacement 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, and the cutting edge is fitted with a curved surface, and the curved surface formed is the back cutting edge.

[0014] Further, in step 2, the shape value point on the cutting edge is assumed to be, where ,in , establish tool cutting angle reference planes including base plane, cutting plane and orthogonal plane;

[0015] Set line segment lies on the intersection of the orthogonal plane and the base plane, and The direction points inward; set the type value point in the orthogonal plane Make a line segment ,make Point to the inside of the blade teeth so that the angle Equal to the cutting front angle of the set cutting edge; Do surface fitting, where , the surface obtained is called a surface ;Will and Connect them with line segments. Constructed as a filled surface ,in ; Surface and Surface Together they form the front cutting edge.

[0016] Furthermore, in steps one to three, the method for selecting the shape value point of the cutting edge is to construct a number of tangent arc segments on the conjugate surface of the tooth surface of the special-shaped gear, and discretize the arc segments on the arc according to the fixed center angle, so as to obtain the shape value point.

[0017] Furthermore, in steps one to three, the cutting edge is obtained by fitting the model value points through the curve fitting function of the UG10.0 modeling module; the rear face modeling is constructed using the surface modeling function of the UG10.0 modeling module; and the front face modeling is constructed using the surface modeling function of the UG10.0 modeling module.

[0018] Further, in step 1 to step 3, the rake face processed for the first time during the rough machining of the cutter body is recorded as the first rake face, and the flank face processed for the first time is recorded as the first flank face; the rake face processed for the last time is recorded as the expected rake face, and the flank face processed for the last time is recorded as the expected flank face;

[0019] Obtain a first machining depth between a first rake face and an expected rake face, and obtain a second machining depth between a first flank face and an expected flank face; obtain an area to be machined between the rake face and the flank face during rough machining, mark the area to be machined according to the number of feeds and feed depth during rough machining of each flank face, and obtain a retraction depth;

[0020] The first processing angle of the first front cutting surface is adjusted based on the retraction depth and the cutting front angle corresponding to the expected front cutting surface, so that the intersection between the first front cutting surface formed by the first processing and the expected back cutting surface retains two retraction depths to obtain a formed front cutting surface; based on the formed front cutting surface, the first processing angle is further adjusted to obtain the expected front cutting surface.

[0021] Furthermore, in steps one to three, the shaping of the front cutting edge is constructed using the surface modeling function of the UG10.0 modeling module.

[0022] The following beneficial effects are achieved by adopting the above scheme:

[0023] (1) Through surface fitting, the design parameters of the tooth cutter, such as the blade shape, front angle, and back angle, can be optimized to make the tool more efficient during the processing. It can also detect errors caused by human factors or equipment precision limitations during the design stage and avoid the accumulation of errors during the processing process.

[0024] (2) The cutting angle of the curved rake face of the special-shaped tooth is consistent with that of the cutting edge. The working rake angle of each point on the cutting edge is constant when participating in cutting. The cutting force is more evenly distributed at each cutting point, maintaining contact stability during the cutting process, which helps to reduce the roughness of the workpiece surface, thereby improving surface quality and improving machining accuracy.

[0025] (3) During the rough machining process, the machining conditions between the rake face and the flank face are adjusted to ensure the stability of the tool retraction during the machining of the rake face, so as to ensure that the cutting front angles of the rake face and the cutting edge are consistent.

[0026] (4) The consistent cutting rake angle keeps the cutting conditions of each cutting edge the same, reduces tool wear, ensures the smoothness of the cutting process, helps reduce the chatter and vibration of the machine tool, and thus improves machining accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The figure is a schematic structural diagram of a tooth-cutting cutter with a curved rake face and special-shaped teeth according to an embodiment of the present invention.

[0028] Figure 2 The figure is a schematic diagram of the selection of the profile points of the tooth-cutting cutter with a curved rake face of a special-shaped tooth according to an embodiment of the present invention.

[0029] Figure 3 for Figure 1 Schematic diagram of the back face construction.

[0030] Figure 4 for Figure 1 Schematic diagram of the coordinate establishment of the front cutting edge.

[0031] Figure 5 for Figure 1 Schematic diagram of the construction of the front cutting edge.

[0032] Among them, the figure marks in the drawings of the specification include: tooth 1, conjugate surface 10, cutting edge 2, front cutting surface 3, back cutting surface 4, profile point 5, arc segment 6. DETAILED DESCRIPTION

[0033] The following is further described in detail through specific implementation methods:

[0034] Embodiment 1:

[0035] The embodiment is basically as follows Figures 1 to 5 As shown: a special-shaped tooth curved front blade cutting tooth cutter, comprising a cutter body and a plurality of cutter teeth 1 arranged circumferentially along the outer edge of the cutter body, wherein the cutter teeth 1 are straight teeth or oblique teeth.

[0036] The tooth 1 includes a cutting edge 2, a front cutting face 3 and a back cutting face 4, and the cutting front angle of the cutting edge 2 is 5-10°; the cutting edge 2 is obtained by fitting the shape value point 5 selected by the conjugate surface 10 of the tooth surface of the special-shaped gear according to the constraint conditions, and the shape value point 5 is fitted by the fitting curve; the back cutting face 4 is a free-form surface composed of a series of cutting edges 2 obtained by intersection; the front cutting face 3 is a free-form surface for controlling the constant cutting front angle of the cutting edge 2, and the free-form surface is constructed in the UG10.0 modeling module through the surface modeling function.

[0037] For example, through surface fitting, the design parameters of the tooth cutter such as the blade shape, front angle, and back angle can be optimized, and a cutting front angle that conforms to the processing parameters and workpiece parameters can be established, making the tool more efficient during the processing process. Errors caused by human factors or equipment precision limitations during the design stage can be discovered to avoid the accumulation of errors during the processing process.

[0038] The design and shaping method of the above-mentioned special-shaped tooth curved rake face 3 tooth-cutting cutter comprises the following steps:

[0039] Step 1. Establish the conjugate tooth surface of the tooth surface to be machined according to the machining parameters and workpiece parameters, select some points on the conjugate tooth surface as the cutting edge 2 type value point 5 according to the constraint conditions, assume that the tooth surface of the special-shaped tooth in contact with the cutting edge 2 is the P tooth surface, and establish the conjugate tooth surface model of the P tooth surface according to the conjugate principle, select some points on the conjugate tooth surface of the P tooth surface according to the constraint conditions as the cutting edge 2 type value point 5, and fit the cutting edge 2 type value point 5 with a spline curve to obtain a spatial curve. This curve is the cutting edge 2, and the cutting edge 2 is obtained by fitting the type value point 5 through the curve fitting function of the UG10.0 modeling module.

[0040] For example, a conjugate tooth surface of the tooth surface to be machined is established according to the machining parameters and workpiece parameters to determine the kinematic relationship between the geometric features and the tooth cutting machining, to ensure that the cutting edge 2 moves along the correct path during the machining process and to achieve consistency in the cutting front angle.

[0041] Step 2: Establish the rake face 3. Based on the cutting edges 2 formed in step 1, set the profile point 5 on the cutting edge 2 as ,in , establish the tool cutting angle reference plane including the base plane, cutting plane and orthogonal plane; set the line segment lies on the intersection of the orthogonal plane and the base plane, and The direction points inward; set the type value point 5 in the orthogonal plane Make a line segment ,make Point to the inside of tooth 1, so that the angle Equal to the cutting front angle of the set cutting edge 2; Do surface fitting, where , the surface obtained is called a surface ;Will and Connect them with line segments. Constructed as a filled surface ,in ; Surface and Surface Together they form the front cutting surface 3. The front cutting surface 3 modeling is constructed using the surface modeling function of the UG10.0 modeling module.

[0042] For example, through the surface and Surface Fitting is performed to keep the cutting conditions constant. The cutting rake angle of the curved rake face 3 of the special-shaped tooth is made consistent with that of the cutting edge 2. The working rake angle of each point on the cutting edge 2 is constant when participating in cutting. The distribution of cutting force at each cutting point is more uniform, and the contact stability during the cutting process is maintained, which helps to reduce the roughness of the workpiece surface, improve the surface quality, and improve the machining accuracy.

[0043] Step 3: Establish the flank 4. Based on the several cutting edges 2 formed in step 1, the tooth surface of the special-shaped tooth in contact with the cutting edge 2 is set as the P tooth surface. According to the conjugate principle, establish the conjugate tooth surface model of the P tooth surface; change the displacement coefficient of the conjugate tooth surface of the P tooth surface to obtain several conjugate tooth surfaces of the P tooth surface, and obtain several cutting edges 2. Fit the cutting edge 2 to form a curved surface, and the curved surface formed is the flank 4. The flank 4 modeling is constructed using the surface modeling function of the UG10.0 modeling module.

[0044] For example, by sequentially fitting the cutting edges 2 to construct the back face 4, based on the cutting front angle consistency, the cutting conditions of each cutting edge 2 are kept the same, so that the shape of the back face 4 can still maintain the consistency of the cutting front angle after the cutting edge 2 is formed, thereby ensuring the stability of the cutting process and helping to reduce the chatter and vibration of the machine tool to improve the processing accuracy.

[0045] Embodiment 2:

[0046] The difference from the above-mentioned embodiment lies in that: in steps one to three of the design and shaping method of the tooth-cutting cutter with a curved front cutting edge 3 for special-shaped teeth, the front cutting edge 3 processed for the first time during the rough machining of the cutter body is referred to as the first front cutting edge, and the back cutting edge 4 processed for the first time is referred to as the first back cutting edge; the front cutting edge 3 processed for the last time is referred to as the forming front cutting edge, and the back cutting edge 4 processed for the last time is referred to as the forming back cutting edge.

[0047] Obtain a first machining depth between the first rake face and the formed rake face, and obtain a second machining depth between the first flank face and the formed flank face; obtain an area to be machined between the rake face 3 and the flank face 4, mark the area to be machined according to the number of feeds and feed depth during each rough machining of the flank face 4, and obtain a retraction depth.

[0048] The first machining angle of the first rake face is adjusted based on the retraction depth and the cutting front angle of the formed rake face, so that the intersection between the first rake face formed by the first machining and the formed flank face retains two retraction depths. The modeling of the formed rake face is constructed using the surface modeling function of the UG10.0 modeling module.

[0049] For example, during the rough machining process, based on the angle between the front cutting edge 3 and the back cutting edge 4, it is possible to ensure that the back cutting edge 4 is modified during the subsequent fine machining process, gradually reduce the cutting resistance when machining the front cutting edge 3, improve control stability, and reduce the cutting amount at the retraction position to ensure stability, so as to reduce the machining errors caused by vibration caused by collision and extrusion during machining, so as to ensure that the cutting front angles of the front cutting edge 3 and the cutting edge 2 are consistent.

[0050] Embodiment 3:

[0051] The difference from the above embodiment is that an image capture module, a light angle irradiation module and a depth comparison module are provided. The image capture module is used to collect the processed image of the cutting edge 2 during the cutting process, and send the processed image to the depth comparison module. The light angle irradiation module is used to irradiate the processed area of ​​the cutting edge at a specified angle after the processing of a cutting edge 2 is completed, and send a marking instruction to the depth comparison module, and the depth comparison module marks the processed image at the current time based on the marking instruction.

[0052] The depth comparison module is used to obtain the corresponding dark area brightness based on the processed image, and compare the dark area brightness with the set standard brightness. If the dark area brightness is greater than or equal to the standard brightness, the current cutting edge mark is fed normally. If the dark area brightness is less than the standard brightness, an adjustment instruction is sent to the light angle illumination module until the dark area brightness is greater than or equal to the standard brightness.

[0053] For example, in different processing stages, during the initial processing, the light irradiation angle is inconsistent due to the different clamping positions during the previous part processing. The angle is continuously adjusted to ensure that the light illuminates the bottom of the processed area, thereby facilitating subsequent comparison and verification of the consistency of the cutting edge.

[0054] The depth comparison module is also used to compare the marks of the front and rear cutting edges for consistency during a processing process. If they are consistent, a normal instruction is sent to the outside world; if they are inconsistent, a warning instruction is sent to the outside world.

[0055] The consistency of the marks on the front and rear cutting edges is compared to determine the consistency of the feed depth, to provide reminders for work, and to ensure timely adjustments to the stability of the cutting process to improve machining accuracy.

[0056] The above is only an embodiment of the present invention, and the common knowledge such as the known specific structure and / or characteristics in the scheme is not described in detail here. It should be pointed out that for those skilled in the art, several deformations and improvements can be made without departing from the structure of the present invention, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection 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 design and shaping method for a tooth-cutting cutter with a curved rake face of a special-shaped tooth, characterized in that: The toothed cutter with a curved rake face of a special-shaped gear comprises a cutter body and a plurality of cutter teeth arranged circumferentially along the outer edge of the cutter body; the cutter teeth comprise a cutting edge, a rake face and a flank face; the cutting edge is a shape value point selected from a conjugate surface of the tooth surface of the special-shaped gear according to a constraint condition, and is obtained by fitting the shape value point through a fitting curve; the flank face is a free-form surface composed of a series of cutting edges obtained by intersection; the rake face is a free-form surface for controlling a constant cutting front angle of the cutting edge; The design and modeling method comprises the following steps: Step 1: Establish a conjugate tooth surface of the tooth surface to be processed according to the processing parameters and the workpiece parameters, select some points on the conjugate tooth surface as cutting edge value points according to the constraint conditions, and fit the cutting edge value points with a spline curve to obtain a spatial curve to form a cutting edge; Step 2, establishing a rake face, based on the plurality of cutting edges formed in step 1, forming a curved surface in a constant direction of the cutting rake angle of the cutting edge to establish the rake face; Step 3: Establish the back face, based on the several cutting edges formed in step 1, cut the cutting edges to obtain a free-form surface, and construct the surface modeling; In step 1 to step 3, the tooth surface of the special-shaped tooth in contact with the cutting edge is assumed to be the P tooth surface, and a conjugate tooth surface model of the P tooth surface is established according to the conjugate principle; the displacement 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, and the cutting edges are fitted with a curved surface, and the curved surface formed is the back cutting edge; In step 2, let the shape value point on the cutting edge be ,in , establish tool cutting angle reference planes including base plane, cutting plane and orthogonal plane; Set line segment lies on the intersection of the orthogonal plane and the base plane, and The direction points inward; set the type value point in the orthogonal plane Make a line segment ,make Point to the inside of the blade teeth so that the angle Equal to the cutting front angle of the set cutting edge; Do surface fitting, where , the surface obtained is called a surface ;Will and Connect them with line segments. Constructed as a filled surface ,in ; Surface and Surface Together they form the front cutting edge.

2. The design and shaping method of the tooth-cutting cutter with a curved rake face of a special-shaped tooth according to claim 1, characterized in that: In steps 1 to 3, the method for selecting the value point of the cutting edge is to construct a number of tangent arc segments on the conjugate surface of the tooth surface of the special-shaped gear, discretize the arc segments on the arc according to the fixed center angle, and then obtain the value point.

3. The design and shaping method of the tooth-cutting cutter with a curved rake face of a special-shaped tooth according to claim 2, characterized in that: In step 1 to step 3, the cutting edge is obtained by fitting the type value points through the curve fitting function of the UG10.0 modeling module; the rear face modeling is constructed using the surface modeling function of the UG10.0 modeling module; and the front face modeling is constructed using the surface modeling function of the UG10.0 modeling module.

4. The design and shaping method of the tooth-cutting cutter with a curved rake face according to claim 3 is characterized by: In steps 1 to 3, the rake face processed for the first time during the rough machining of the cutter body is recorded as the first rake face, and the flank face processed for the first time is recorded as the first flank face; the rake face processed for the last time is recorded as the expected rake face, and the flank face processed for the last time is recorded as the expected flank face; Obtain a first machining depth between a first rake face and an expected rake face, and obtain a second machining depth between a first flank face and an expected flank face; obtain an area to be machined between the rake face and the flank face during rough machining, mark the area to be machined according to the number of feeds and feed depth during rough machining of each flank face, and obtain a retraction depth; The first processing angle of the first front cutting surface is adjusted based on the retraction depth and the cutting front angle corresponding to the expected front cutting surface, so that the intersection between the first front cutting surface formed by the first processing and the expected back cutting surface retains two retraction depths to obtain a formed front cutting surface; based on the formed front cutting surface, the first processing angle is further adjusted to obtain the expected front cutting surface.

5. The design and shaping method of the tooth-cutting cutter with a curved rake face of a special-shaped tooth according to claim 4, characterized in that: In step 1 to step 3, the shaping of the front cutting edge is constructed using the surface modeling function of the UG10.0 modeling module.

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