Internal spline grinding forming cutter

Abstract

The utility model relates to the technical field of spline machining, in particular to an internal spline grinding forming tool which comprises a tool bit and a tool bar, and the tool bit and the tool bar are of an integrally-formed structure. The outer diameter of the tool bit is larger than that of the tool bar, and hollow flow channels are further formed in the tool bit and the tool bar and used for allowing cooling liquid to pass through. Spline machining teeth are uniformly distributed on the tool bit, and the tooth number and modulus of the spline machining teeth are matched with those of a spline to be machined; a lead groove is further formed in the tooth surface of the spline machining tooth; the tooth surface of the spline machining tooth is further coated with a grinding layer. According to the utility model, the hollow forming cutter made of superhard materials is researched and developed, finish machining and trimming of the tooth surface of the internal spline are carried out in an axial reciprocating motion mode or a cutter radial feeding grinding mode, the industrial problem is well solved, and the precision after machining completely meets the application size requirement.

Description

Technical Field

[0001] The utility model relates to the technical field of spline processing and metal grinding processing, in particular to an internal spline grinding and forming tool. Background Art

[0002] Due to the development of electric vehicles, the use of motor shafts for drive motors has increased. The connections for motor-driven gearbox rotation are mostly splined, requiring high precision. For precision control of internal spline products, the industry currently uses heat treatment tooling to reduce deformation, but the accuracy still falls far short of application requirements. For workpieces that exceed tolerances after heat treatment, a shaped push tool is used to correct the deformation, but the tool is prone to chipping and the workpiece accuracy cannot be guaranteed. Gear products with internal splines also face the problem of internal spline deformation after heat treatment. If conditions permit for through-hole internal splines, hard drawing after heat treatment can be used, but this is subject to high tool costs and large equipment investment, making it impossible to process blind-hole internal spline products.

[0003] After heat treatment, workpieces with internal splines can deform, becoming dimensionally out of tolerance and failing to meet service requirements. Due to the unique nature of the workpiece and limited space, traditional finishing methods are inapplicable to this deformation problem, especially for blind internal splines. Currently, there are no effective processing methods, and the industry generally employs specially designed tooling during the heat treatment process to minimize heat treatment deformation. Traditional processing methods, such as spline forming pushers and broaches, primarily use the blade as the cutting surface; however, this still fails to meet service requirements. Summary of the Invention

[0004] In order to solve the above-mentioned shortcomings and deficiencies of the existing internal spline processing technology, the utility model provides an internal spline grinding and forming tool that performs fine processing of the internal spline tooth surface in a mode of axial reciprocating motion and radial feed grinding of the tool to improve the spline processing accuracy.

[0005] The utility model adopts the following technical solutions to achieve the above purpose:

[0006] A tool for grinding and forming an internal spline, comprising a cutter head and a cutter rod, wherein the cutter head and the cutter rod are an integrally formed structure; the outer diameter of the cutter head is larger than the outer diameter of the cutter rod, and both are provided with a hollow flow channel inside, wherein the hollow flow channel is used to pass coolant; the cutter head is provided with evenly distributed spline processing teeth, the number of teeth and the module of the spline processing teeth match the spline to be processed; a lead groove is also provided on the tooth surface of the spline processing teeth; and the tooth surface of the spline processing teeth is also coated with a grinding layer.

[0007] As a preferred technical solution: the number of teeth of the spline machining teeth is at least one less than the number of teeth of the spline workpiece to be machined.

[0008] A further preferred technical solution is that the lead groove is a multi-start spiral groove.

[0009] A further preferred technical solution is: the grinding layer is made of superhard material microparticles, which serve as the cutting surface for grinding.

[0010] A further preferred technical solution is: the cutter head and the cutter rod are made of CBN material.

[0011] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention has developed a hollow forming tool made of superhard material, and the superhard particles coated on the outer surface of the forming tool are used as the cutting edge for grinding; compared with push cutters and broaches, the present invention uses the outer surface as the cutting edge; and the tooth surface of the internal spline workpiece is finely processed in the mode of axial reciprocating motion and radial feed grinding of the tool, which well solves the industry problem of finishing the internal spline products, especially the blind hole internal spline products after heat treatment deformation. After the forming tool enters the spline, since the number of teeth of the tool is more than one tooth less than the number of teeth of the internal spline of the workpiece, the two tooth surfaces of the tool and the tooth surface of the workpiece are ground under non-repeated contact surfaces, avoiding the inconsistency caused by the excessive precision of individual teeth; the precision after processing fully meets the dimensional requirements of the application. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0013] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0014] Figure 2 It is an internal sectional view of the present invention.

[0015] In the figure: 1. Cutter head; 2. Cutter shank; 3. Hollow flow channel; 4. Spline processing teeth; 5. Lead groove; 6. Grinding layer. DETAILED DESCRIPTION

[0016] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0017] It should be noted that, in the specific embodiments of the present invention, the terms "include", "comprises" or any other variations 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 includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the phrase "including a ..." or other limiting elements does not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0018] In the description of this utility model, unless otherwise expressly specified or limited, the terms "installed," "connected," "connected," and "provided with" that may appear should be understood in a broad sense. For example, they may refer to fixed connection, detachable connection, or integral connection; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; or internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on specific circumstances.

[0019] Example: Figures 1 to 2The figure shows an internal spline grinding tool, comprising a cutter head 1 and a shank 2, with the cutter head 1 and shank 2 forming an integral structure. The cutter head 1 and shank 2 are made of CBN material. The outer diameter of the cutter head 1 is larger than that of the shank 2, and both are internally provided with a hollow channel 3. The cutter head is in the shape of a hollow external spline, and the hollow channel 3 is used to pass coolant. This arrangement allows the coolant to enter through the hollow channel and then flow out through the spline grinding surface, discharging particles generated by grinding while preventing abnormally high temperatures in the tool during spline machining. The cutter head 1 is provided with evenly distributed spline machining teeth 5. The spline machining tooth surface is the tool grinding tooth surface, which is the part of the tool that contacts the workpiece grinding tooth surface when grinding the internal spline. The number of teeth and module of the spline machining teeth 5 match the spline to be machined; the number of teeth of the spline machining teeth 5 is at least one less than the number of teeth of the spline workpiece to be machined. The tooth surface of the forming tool is made of superhard material particles coated or sintered; the recommended superhard materials include CBN, etc., and the tool has high durability. After the forming tool enters the spline, since the number of teeth of the tool is more than one tooth less than the number of teeth of the spline in the workpiece, the two tooth surfaces of the tool and the tooth surface of the workpiece are ground under non-repeated contact surfaces, avoiding the inconsistency caused by the precision of individual teeth. A lead groove 6 for accommodating and discharging grinding particles is also provided on the tooth surface of the spline processing tooth 5; the lead groove 6 is a multi-head spiral groove. Among them, the number of spiral heads is adjusted according to the needs of processing spline products. There is a spiral guide groove on the surface of the tool to facilitate the discharge of the grinding material; the grinding amount feed can be precisely adjusted, which well guarantees the dimensional requirements of the spline span, and the accuracy can reach within 5 levels, which fully meets the use requirements of the product. The tooth surface of the spline processing tooth 5 is also coated with a grinding layer 7. The grinding layer 7 is superhard material microparticles, which serves as the cutting surface for grinding. The tooth surface normal of the forming tool is reduced as needed to facilitate the tool to enter the workpiece. The tooth surface shape is the surface shape cultivated at the relative position of the tool and the workpiece, rather than uniformly removing part of the tooth surface.

[0020] Working principle: The spline workpiece to be processed is installed on the hollow chuck of the external equipment. The spindle slide moves toward the forming tool before clamping. The forming tool is fixedly installed on the auxiliary equipment and can move back and forth. Let the forming tool enter the workpiece spline and adjust the feed position. At the same time, before clamping the workpiece, the tool is radially fed to make the tooth surfaces on both sides of the spline in the workpiece close to the tooth surfaces on both sides of the tool, and then the hollow chuck is clamped. The forming tool starts to perform axial reciprocating motion according to the adjusted reciprocating position by the reciprocating motor through the connecting rod to drive the forming movable tool slide; then, coolant is fed in while the tool reciprocates to start tooth surface grinding, and it exits after reaching the set grinding position, completing a grinding process. This grinding method can achieve relatively high spline accuracy due to its simple grinding amount setting, high repeatability, and high concentricity.

[0021] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An internal spline grinding and forming tool, characterized by: The tool comprises a cutter head (1) and a cutter bar (2), and the cutter head (1) and the cutter bar (2) are an integrally formed structure; the outer diameter of the cutter head (1) is larger than the outer diameter of the cutter bar (2), and a hollow flow channel (3) is provided inside the cutter head (1) for passing a coolant; the cutter head (1) is provided with evenly distributed spline processing teeth (4), and the number of teeth and the module of the spline processing teeth (4) match the spline to be processed; a lead groove (5) for accommodating and discharging grinding particles is provided on the tooth surface of the spline processing teeth (4); and a grinding layer (6) is coated on the tooth surface of the spline processing teeth (5).

2. The internal spline grinding and forming tool according to claim 1, characterized in that: The number of teeth of the spline processing teeth (5) is at least one less than the number of teeth of the spline workpiece to be processed.

3. The internal spline grinding and forming tool according to claim 2, characterized in that: The lead groove (5) is a multi-headed spiral groove.

4. The internal spline grinding and forming tool according to claim 3, characterized in that: The grinding layer (6) is a cutting surface made of superhard material microparticles.

5. The internal spline grinding and forming tool according to claim 4, characterized in that: The cutter head (1) and the cutter rod (2) are made of CBN material.

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