GB2605739A - Detachable multi-blade skiving tool with staggered blades and assembling method therfor - Google Patents

Abstract

The tool includes a pressing end cover 5 to fasten a cutter blade set 2 to a tool substrate 1 through a connecting piece. The outer diameters and tooth profiles of cutter blades in the set decrease in sequence from top to bottom. Each of the cutter blades in the set have an identical number of teeth. The gear teeth of two adjacent cutter blades are staggered. An uppermost cutter blade in the set is configured for finish machining, and the other cutter blades are configured for rough machining. The cutter blade set includes a first cutter blade 21 located above second cutter blades 22. A symmetrical centreline of a tooth profile of each gear tooth of the second cutter blades deviates from an end surface from a symmetrical centreline of a tooth profile of a respective gear tooth on the first cutter blade by a predetermined angle. Two adjacent second cutter blades deviate in opposite directions. One pass of the multi-blade skiving tool is equivalent to multiple passes of a conventional single-blade tool, which improves the skiving efficiency. The staggered blades are conducive to the evacuation of chips, thereby reducing the cutting load and prolonging the tool life.

Description

DETACHABLE MULTI-BLADE SKIVING TOOL WITH STAGGERED

BLADES AND ASSEMBLING METHOD THEREFOR

Technical Field

The present invention relates to the technical field of gear machining, and particularly to a detachable multi-blade skiving tool with staggered blades and an assembling method therefor.

Background

Power skiving, also known as scudding or slicing, is a novel of cylindrical gear machining technology developed to overcome the limitations of conventional gear machining methods. It has the characteristics of high efficiency, high precision, dry cutting. However, the processing of power skiving is usually high-speed, dry cutting with extremely harsh cutting conditions. Under the coupling effect of instantaneous high cutting heat and large cutting force, the complex chip deformation is not conducive to the evacuation of chips, and the participation of the entire cutter blade of the tool in cutting has large load impact on the tool. The cutter blade of an existing single-blade skiving tool wears quickly, and is prone to tip breakage, resulting in a shortened tool life. In order to improve the cutting conditions and reduce the risk of tip breakage of the skiving tool, multiple or even dozens of micro-feeds of the tool are usually adopted. However, the multiple micro-feeds are at the expense of reducing the machining efficiency, and double or even increase the machining time multiple folds, which greatly affects the machining efficiency.

In addition, existing single-blade skiving tools usually use the center feed method, and the chips generated in this feed method are mostly "W-shaped chips, which are not easy to be quickly cut off and evacuated. On the one hand, the chip flow has great interference to the tool. On the other hand, the chips are easy to stick to the processed surface of the workpiece and the rake face of the cutter teeth, which increases the friction force and leads to a poor surface quality of the workpiece. In addition, due to the high temperature of the cutting edge of the tool, the hardness and wear resistance of the skiving tool are significantly reduced, reducing the tool life.

Summary

To overcome the drawbacks in the prior art, the present invention provides a detachable multi-blade skiving tool with staggered blades and an assembling method therefor, to solve the problems of large impact on the entire cutter blade of the tool with full load and difficulty in cutting off and evacuating the chips during gear skiving.

The above technical object of the presen nvention is atta ned with the following technical means.

A detachable multi-blade skiving tool with staggered blades is provided, including a tool substrate, a set of cutter blade, and a pressing end cover, where the pressing end cover is configured to fasten the cutter blades to the tool substrate through a connecting piece; outer diameters and tooth profiles of cutter blades in the cutter blade set respectively decrease in sequence in a direction from top to bottom; each of the cutter blades in the cutter blade set includes an identical number of teeth; gear teeth of adjacent two of the cutter blades are staggered; and an uppermost cutter blade in the cutter blade set is configured for finish machining to obtain a tooth profile of a workpiece that meets a requirement, with the other cutter blades being configured for rough machining.

Preferably, the cutter blade set includes a first cutter blade and a plurality of second cutter blades, the first cutter blade is located above the second cutter blades, a symmetrical center line of a tooth profile of each gear tooth of the plurality of second cutter blades is deviated on an end surface from a symmetrical center line of a tooth profile of a respective gear tooth on the first cutter blade by a predetermined angle, and adjacent two of the second cutter blades are deviated in opposite directions.

Preferably, a calculation formula for an outer diameter 6101 of each of the second cutter blades is cim=d0-(1-0.9*0.65('-')*2*H, where, dm) represents an outer diameter of the first cutter blade, represents a tooth groove depth of a gear workpiece to be machined, i represents a serial number of any one of the second cutter blades, iE [1,t], and i is a positive integer.

Preferably, tooth profile parameters of the first cutter blade are identical to tooth profile parameters of the second cutter blades except for modulus, and a calculation formula for a modulus mi of each of the second cutter blades is: ni,=da1/[zt+2(hao-Ex0())], where, zt represents a tooth number of the tool, hao represents an addendum coefficient, and xflo represents a profile shift coefficient.

Preferably, a rake angle of each of the second cutter blades is 0°, and a relief angle of each of the second cutter blades is 9° to 180 Preferably, a thickness of the first cutter blade is greater than a thickness of the second cutter blade.

Preferably, a circular through hole is provided on an end surface of the tool substrate, and a distance between a central axis of the circular through hole and a central axis of the tool substrate is a first positioning hole is provided on an end surface of the first cutter blade, a center of the first positioning hole is located on a symmetrical center line of a tooth profile of any cutter tooth, a diameter of the first positioning hole is equal to a diameter of the circular through hole, and a distance between a central axis of the first positioning hole and a central axis of the first cutter blade is Rp; and a second positioning hole is provided on an end surface of the second cutter blade, a center of the second positioning hole is located on a symmetrical center line of a tooth profile of any cutter tooth, a distance between a central axis of the second positioning hole and a central axis of a respective one of the second cutter blades is Rp, and a diameter of the second positioning hole is greater than the diameter of the first positioning hole.

Preferably, a calculation formula for the diameter of the second positioning hole and the diameter of the first positioning hole is: DI=D0+2R1,*sin 0, where, Do represents the diameter of the first positioning hole, Di represents the diameter of the second positioning hole, and 0 represents a deviation angle of a symmetrical center line of a tooth profile of the first cutter blade relative to a symmetrical center line of a tooth profile of the respective one of the second cutter blades on the end surface.

Preferably, a calculation formula for 0 is 0=(tanat-tanarkao-ai)*(f, where, ao represents a pressure angle on the first cutter blade, the pressure angle is measured at an intersection of an involute tooth profile and a circular arc with a diameter d,, and ao=acos[(inezt*cosa,z)/d,,]; al represents a pressure angle on a second cutter blade of the second cutter blades being in contact with the first cutter blade, the pressure angle is measured at an intersection of an involute tooth profile and a circular arc with a diameter d", and al=acos[(rni*zi*cosan)/d"]; and 4r represents a setting coefficient of the deviation angle, andE [0.6,1].

Preferably, the connecting piece includes a location pin, a binding screw, and a plurality of fastening screws The present invention also provides a method for assembling the detachable multi-blade skiving tool with the staggered blades as described above, including: first, passing the location pin through the second positioning hole and the first positioning hole in sequence, so that the location pin extends into the circular through hole to limit a positional relationship of the cutter blades in the cutter blade set relative to the tool substrate, so that the cutter teeth of the cutter blades are in one-to-one correspondence; sequentially numbering the plurality of second cutter blades in descending order of outer diameter, and rotating the odd-numbered second cutter blades in turn, to make the corresponding second positioning holes in contact with one side of the location pin for positioning; rotating the even-numbered second cutter blades, to make the corresponding second positioning holes in contact with the other side of the location pin for positioning; and tightly pressing the pressing end cover onto an end surface of the tool substrate by a plurality of fastening screws, so that the cutter blade set and the tool substrate are coupled together.

The present invention has the following beneficial effects.

The skiving tool of the present invention adopts a detachable multi-blade structure, and one pass of the multi-blade skiving tool is equivalent to multiple passes of a conventional single-blade tool, which greatly improves the machining efficiency. The tool substrate does not participate in cutting and can be reused, thereby avoiding the waste of tool material after the conventional single-bladed skiving tool is scrapped. The cutter blades are flexible to install and remove and have good regrinding performance. All the cutter blades except the first cutter blade have a low requirement on the profile precision, which reduces the grinding and machining costs of the tool.

The skiving tool of the present invention adopts a novel structure of multiple staggered blades, which can avoid full-load cutting of the entire cutter blade of the tool and convert the intermittent impact load in the cutting process into small continuous loads to realize load balancing and vibration reduction, and can alleviate the difficulty in cutting off and evacuating chips in the cutting process to prolong the tool life.

Brief Description of the Drawings

FIG. 1 is a detachable multi-blade skiving tool with staggered blades according to an embodiment of the present invention.

FIG. 2 is a schematic exploded view of the multi-blade skiving tool in FIG. 1.

FIG. 3 is a front view of the multi-blade skiving tool in FIG. 1.

FIG. 4 shows a cutting process of an existing single-blade skiving tool.

FIG. 5 is an envelope trajectory of each layer of cutter blade in FIG. 1.

FIG. 6 shows a load received by each layer of cutter blade in FIG. 1.

FIG. 7 is a schematic view of a position of a first positioning hole in the first cutter blade in FIG. 1.

FIG. 8 is a schematic view of a position of a second positioning hole in the second cutter blade in FIG. I FIG. 9 is a schematic view showing a calculation of a diameter of a location pin and a deviation angle of a gear tooth in each layer of cutter blade in FIG. 1.

FIG. 10 is a partial enlarged view of a tooth profile of each layer of the cutter blade in the cutter blade set in FIG. 1 FIG. 11 is a three-dimensional model of undeformed chips formed through cutting by the skiving tool in FIG. 1.

FIG. 12 shows a morphology of undeformed chips formed through cutting by the skiving tool in FIG. 1 in a tooth groove.

FIG. 13 is a three-dimensional model of undeformed chips formed through cutting by an existing single-blade skiving tool.

FIG. 14 shows a morphology of undeformed chips formed through cutting by an existing single-blade skiving tool in a tooth groove.

Detailed Description of the Embodiments

Embodiments of the present invention will be exemplarily described in detail hereinafter with reference to accompanying drawings in which the same or like reference characters refer to the same or like elements or elements having the same or like functions throughout. The embodiments described below with reference to accompanying drawings are exemplary, and intended to explain, instead of limiting the present invention.

In the description of the present invention, it should be understood that the orientation or positional relationships indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "axial", "radial", "vertical", "horizontal", "inner", "outer", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the apparatus or element described must have a specific orientation or be constructed and operated in a specific orientation, and therefore are not to be construed as limiting the present invention. Moreover, the terms "first" and "second" are used herein for purposes of description, and are not intended to indicate or imply relative importance or implicitly point out the number of the indicated technical feature. Therefore, the features defined by "first", and "second" may explicitly or implicitly include one or more features. In the description of the present invention, "plural" means two or more, unless it is defined otherwise specifically.

In the present invention, unless otherwise clearly specified and defined, the terms "mount", "connect", "couple", "fix" and variants thereof should be interpreted in a broad sense, for example, may be a fixed connection, a detachable connection, or an integral connection; may be a mechanical connection or an electrical connection; or may be a direct connection, an indirectly connection via an intermediate medium, or communication between the interiors of two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

A detachable multi-blade skiving tool with staggered blades according to the embodiments of the present invention is first described below with reference to the accompanying drawings.

In an embodiment of the present invention, a gear workpiece to be machined is an involute cylindrical internal helical gear Known basic parameters of the gear workpiece are shown in Table 1 Table 1 Basic parameters of gear workpiece Modu lus mn Numb Pressure angle a, Helix angle fig Profile shift coeffici ent x, Addend um coeffici ent ha Top clearan cc coeffici ent c Gear width b Precision Requirem ent er of teeth.z, 2 mm 72 200 200 0 1 0.25 30 mm 1S06 (rightward rotation) As shown in FIG. 1, a detachable multi-blade skiving tool with staggered blades according to an embodiment of the present invention includes a tool substrate 1, a cutter blade set 2, a location pin 3, a binding screw 4, a pressing end cover 5, and a plurality of fastening screws 6.

Specifically, the tool substrate I includes a cylindrical section and an annular flange arranged on a circumferential outer side of the cylindrical section. The cylindrical section and the flange are integrally formed. The tool substrate I is only used for installing and fixing the cutter set 2 and does not participate in metal cutting.

The cutter blade set 2 includes a plurality of cutter blades arranged in sequence from top to bottom. All the cutter blades are coaxial and include an identical number of teeth. Each of the cutter blades has a different outer diameter. In a direction from top to bottom, the outer diameters of the cutter blades decrease in sequence and tooth profiles of the cutter blades decrease in sequence. The cutter blade set 2 in this embodiment includes three cutter blades, where an uppermost cutter blade is a first cutter blade 21 which has a largest diameter, and a plurality of second cutter blades 22 are arranged below the first cutter blade 21. The number of the second cutter blades 22 in this embodiment is two. The cutter blade set 2 is sleeved on the cylindrical section of the tool substrate 1 and is arranged below the flange. The first cutter blade 21 is configured for finish machining to obtain a tooth profile of a gear workpiece that meets a requirement. The second cutter blades 22 are configured for rough machining. The tool structure design of such a multi-blade tool of the present invention has the following advantages: One pass of the multi-blade tool is equivalent to multiple passes of a conventional single-blade tool (as shown in FIG. 4). For a gear workpiece with a modulus of 0.8, the conventional single-blade skiving tool requires three passes in order to complete the machining of the entire tooth groove, and the multi-blade skiving tool of the present invention can complete the machining of the entire tooth space by only one pass (as shown in FIG. 5). That is to say, the three layers of cutter blades of the multi-blade tool is equivalent to three passes of the conventional single-blade skiving tool. Therefore, the multi-blade skiving tool of the present invention greatly improves the machining efficiency. The layers of cutter blades are flexible to install and remove and have good regrinding performance. In addition, during sharpening the cutter blades, it is only necessary to ensure the precision of the first cutter blade 21, and the precision of the second cutter blades 22 is smaller than that of the first cutter blade 21, thereby reducing the time and costs required for sharpening the cutter blades of the tool.

In this embodiment, a symmetrical center line of a tooth profile of each gear tooth of the two second cutter blades 22 is deviated on an end surface from a symmetrical center line of a tooth profile of a respective gear tooth on the first cutter blade 21 by a predetermined angle, and the two second cutter blades 22 are deviated in opposite directions. If the number of the second cutter blades 22 is more than two, any two adjacent second cutter blades 22 are deviated in opposite directions.

In this embodiment, the correct tooth profile of the gear workpiece is finally machined by the cutter blade with the largest outer diameter, i.e., the first cutter blade 21. Therefore, the design method of the first cutter blade 21 is the same as the design method of an ordinary single-blade skiving tool. In this embodiment, the tool is designed as a spur tool, where the number of teeth 2./ of the first cutter blade 21 is 36, the pressure angle a, is 200, the helix angle /1, is 0, the profile shift coefficient x,22 is 0, and the installation angle is 20°. To machine the root of the workpiece, the addendum coefficient h,, is 1.45, and the top clearance coefficient a is -0.2. The design precision of the tool is one level higher than the machining precision of the gear workpiece, which is determined as ISO 5. Initial design parameters of the first cutter blade 21 are shown in Table 2.

Table 2 Initial design parameters of first cutter blade Modulu s mo Numbe Pressur e angle a,, Hell x angl e Profile shift coefficie nt xno Addendu m Top clearancecoefficie nt co Installatio n angle": Precision r of fit coeffic en t hao R e quireme nt teeth z, 2 mm 36 20° 0° 0 1.45 -0.2 20° ISO 5 According to the initial design parameters of the first cutter blade 21 in Table 2, an addendum circle calculation formula is obtained from a general gear cutting tool design and calculation method: ct0=ni0*kr+2(hao+x,o)], into which the parameters are substituted to obtain the outer diameter of the first cutter blade 21: da0=77.8 mm. Then, the outer diameters of the second cutter blades 22 are calculated based on a calculation formula: da1=40-(1-0.9*0.65('))*2*H, where, H=mn*(2ha+c) representing a tooth groove depth of the gear workpiece to be machined. 14=4.5 mm. For HI, the parameters are substituted into the formula to obtain the outer diameter of the second cutter blade 22 in the middle layer: d"1=76.9 mm. For i=2, the parameters are substituted into the formula to obtain the outer diameter of the second cutter blade 22 with the smallest outer diameter, i.e., the second cutter blade 22 in the bottom layer: 42=74.1 mm. Therefore, the outer diameters of the three layers of cutter blades in descending order are: 40=77.8 mm, dai=76.9 mm, da2=74.1 mm. The use of the optimal calculation formula for the second cutter blade 22 in the present invention allows for a more reasonable selection of the outer diameters of the cutter blades. As shown in FIG. 6, in a simulated full-tooth-depth cutting process, the loads on the three layers of cutter blades exhibit a trend of high in the middle and low on both sides, i.e., the load of the second cutter blade 22 in the middle layer is higher, and the loads of the first cutter blade 21 and the second cutter blade 22 in the bottom layer are smaller. Such a configuration where the load is mainly distributed on the second cutter blade 22 in the middle layer have the following advantages. On the one hand, the load of the first cutter blade 21 used for finish machining is reduced, thereby reducing the wear of the first cutter blade 21 and ensuring the precision during finish machining. On the other hand, the load of the second cutter blade 22 in the bottom layer is reduced, so as to prevent the cutting depth of the second cutter blade 22 in the bottom layer from being too large to affect the heat dissipation and chip evacuation of the cutter blades.

In order to simplify the design of the tooth profile parameters of the cutter blades, the tooth profile parameters of the first cutter blade 21 are identical to those of the second cutter blades 22 except for modulus. The modulus in, of any second cutter blade 22 can be calculated from the known cia, based on the following calculation formula: ni,=c1mi[zt+2(h0n+x,0)], where, z, represents a tooth number of the tool, h, represents an addendum coefficient, and xn represents a profile shift coefficient. The parameters are substituted into the formula to respectively obtain the moduli of the second cutter blade 22 in the middle layer and the second cutter blade 22 in the bottom layer: mi=1.9769, and nn= 1.9049. Such a method of calculating the moduli of the cutter blades from the outer diameters of the cutter blades is advantageous in that: the cutter blades can be designed by changing the moduli of the cutter blades while keeping the other parameters unchanged, which not only ensures that the tooth profile of the cutter blade decreases with the outer diameter, but also reduces the workload required for tool design.

A rake angle of each cutter blade in the cutter blade set 2 is 0, and a relief angle of each cutter blade in the cutter blade set 2 is 12°. In this embodiment, it is determined that a thickness of the first cutter blade 21 is t0=12 mm, and thicknesses of the second cutter blade 22 in the middle layer and the second cutter blade 22 in the bottom layer are respectively: /1=5 mm and b=5 mm. The thickness /0 is greater than /1 and h, which is advantageous in that: the first cutter blade 21 has a sufficient regrinding amount to prolong the service life of the first cutter blade 21, and the teeth of the first cutter blade 21 have sufficient strength to prevent teeth breakage and tip breakage of the cutter blade under a large impact load, thereby ensuring the reliability of the tool.

A circular through hole 11 with a diameter of Do=5 mm is provided on an end surface of the flange the tool substrate 1, and a distance between a central axis of the circular through hole 11 and a central axis of the tool substrate 1 is R2. Half of a depth of the circular through hole 11 is processed into a positioning hole, and the other half of the depth is processed into a threaded hole.

A diameter of the location pin 3 is equal to a diameter of the circular through hole 11 on the tool substrate 1, and the diameter of the location pin 3 is din=5 mm.

A first positioning hole 211 with a diameter of D0=5 mm is provided on an end surface of the first cutter blade 21. A center of the first positioning hole 211 is located on a symmetrical center line of a tooth profile of any cutter tooth. A diameter of the first positioning hole 211 is equal to the diameter of the circular through hole 11. A distance between a central axis of the first positioning hole 211 and a central axis of the first cutter blade 21 is R. That is, when viewed from the end surface, the center of the first positioning hole 211 is located at an intersection of a circle with a radius of R2=28.5 mm and the symmetrical center line of a tooth profile of any cutter tooth, as shown in FIG. 7.

A second positioning hole 221 with a diameter of Di is provided on an end surface of each of the second cutter blades 22. A center of the second positioning hole 221 is located on a symmetrical center line of a tooth profile of any cutter tooth. A distance between a central axis of the second positioning hole 221 and a central axis of the second cutter blade 22 is Rp, as shown in FIG. 8.

The diameter of the second positioning hole 221 is greater than the diameter of the first positioning hole 211. The diameter Do of the first positioning hole 211 and the diameter DI of the second positioning hole 221 can be determined by the following relational expression: DI=Do + 2Rp*sinI0, where, 0 represents a deviation angle of a symmetrical center line of a tooth profile of a tooth on the first cutter blade 21 relative to a symmetrical center line of a tooth profile of a respective tooth on the second cutter blade 22 on the end surface, as shown in FIG. 9. Preferably, the angle 0 may be calculated by a formula 0=(tanoo-tanao+ao-co)*c;±, where, ao represents a pressure angle on the first cutter blade 21, the pressure angle is measured at an intersection of an involute tooth profile and a circular arc with a diameter ci (as shown in FIG. 9), and ao=acos[(mo*zi*cosanyd,,]=8.9940 4=68.5 mm; al represents a pressure angle on the second cutter blade 22 in contact with the first cutter blade 21, the pressure angle is measured at an intersection of an involute tooth profile and a circular arc with a diameter ci (as shown in FIG. 9), and ai=acosRmi*zt*cosan)/d,1=16.202°; and cc" represents a setting coefficient of the deviation angle, and E[0.6,1]. For (,=0.9, the parameters are substituted into the formula to obtain 0=0.334°. Finally, the 0 value is substituted into the formula DI=Do + 21t1,*sin0 to obtain the diameter of the second positioning hole 221 on the end surface of the second cutter blade 22: Di =5.3323 mm.

A method for assembling the multi-blade skiving tool includes the following steps.

First, the location pin 3 is passed through the second positioning hole 221 and the first positioning hole 211 in sequence, so that the location pin 3 extends into the circular through hole 11 to limit a positional relationship of the cutter blades in the cutter blade set 2 relative to the tool substrate 1, so that the cutter teeth of the cutter blades are in one-to-one correspondence.

The plurality of second cutter blades 22 are sequentially numbered in descending order of outer diameter, and the odd-numbered second cutter blades 22 are rotated in turn, to make the corresponding second positioning holes 221 in contact with one side of the location pin 3 for positioning.

The even-numbered second cutter blades 22 are rotated, to make the corresponding second positioning holes 221 in contact with the other side of the location pin 3 for positioning, so that the tooth profiles of the cutter blades are staggered.

The pressing end cover 5 is tightly pressed onto an end surface of the tool substrate 1 by a plurality of fastening screws 6, so that the cutter blade set 2 and the tool substrate I are coupled together. The pressing end cover 5 also blocks bottom ends of the second positioning holes 221 to prevent the location pin 3 from falling. In addition, the binding screw 4 is inserted from a top end of the circular through hole 11 and threadedly connected to the circular through hole II, thereby tightly pressing the location pin 3 Existing research results show that: in the skiving process, chips may be present in three geometric shapes: T-shaped, L-shaped, and U-shaped. The T-shaped and L-shaped chips have a small contact surface with the rake face, which is conducive to the rapid evacuation of the chips and can reduce the interference of the chip flow on the tool, thereby prolonging the tool life. However, the entire cutter blade of the cutter blade that generates U-shaped chips participates in cutting, and the generated chips cannot be quickly evacuated. On the one hand, the chip flow has great interference to the tool. On the other hand, the chips are easy to stick to the processed surface of the workpiece and the rake face of the cutter teeth, which increases the friction force and leads to a poor surface quality of the workpiece. In addition, due to the high temperature of the cutting edge of the tool, the hardness and wear resistance of the skiving tool are significantly reduced, reducing the tool life.

For the multi-blade skiving tool of the present invention, the relative deviation angles between the cutter blades are controlled, so that the tooth profiles of the cutter blades are staggered. As shown in FIG. 10, this is advantageous in that: chips formed by the staggered blades are I-shaped or L-shaped, and the generation of U-shaped chips can be avoided. Therefore, full-load cutting of the entire cutter blade of the tool is avoided, and the cutting load of a single cutter blade is reduced, thereby facilitating the evacuation of chips and prolonging the tool life.

Finally, final design parameters of each layer of cutter blade are shown in Table 3.

Table 3 Final design parameters of each layer of cutter blade Modul us Num ber of teeth Press ure angle (°) Rak e angl e (°) Top Side Blade thickn ess (mm) Outer diame ter (mm) Deviat ion angle (°) (mm) flank reli.et, . angle relief angle First layer of 2 36 20 0 12 4.424 12 77.8 0 cutter blade Middle layer of 1.9769 36 20 0 12 4.424 5 76.9 0.334 cutter blade Last layer of 1.9049 36 20 0 12 4.424 5 74.1 0.334 cutter blade In order to verify the beneficial effects of the multi-blade skiving tool with staggered edges, simulated cutting was adopted. The morphologies of chips generated by the multi-blade skiving tool with staggered blades and those generated by a single-blade skiving tool without staggered blades were compared under identical workpiece parameters and tool parameters. FIG. 11 and FIG. 12 respectively show a three-dimensional model of undeformed chips formed through cutting by the skiving tool with staggered blades according to the present invention and a morphology of the undeformed chips in a tooth groove, where the chips are mainly present on the right side of the tooth groove, and the undeformed chips exhibit an L-shape when evacuated from the tooth groove. FIG. 13 and FIG. 14 respectively show a three-dimensional model of undeformed chips formed through cutting by an existing single-blade skiving tool and a morphology of the undeformed chips in a tooth groove, where the chips are evenly distributed on both sides of the tooth groove, and the undeformed chips exhibit a U-shape when evacuated from the tooth groove. Therefore, the simulated cutting results show that the detachable multi-blade skiving tool with the staggered blades provided by the present invention can effectively solve the problems of full-load cutting of the entire cutter blade of the tool and difficulty in cutting off and evacuating the chips during power gear skiving, and prolong the tool life.

In the description of the specification, the description with reference to the terms "an embodiment", "some embodiments", "example", "specific example", or "some example" and so on means that specific features, structures, materials or characteristics described in connection with the embodiment or example are embraced in at least one embodiment or example of the present invention. In the present specification, the illustrative expression of the above tenns is not necessarily referring to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any suitable manner in one or more embodiments.

Although the embodiments of the present invention have been illustrated and described above, it is to be understood that the above embodiments are exemplary and not to be construed as limiting the present invention, and that changes, modifications, substitutions and alterations can be made by those skilled in the art without departing from the scope of the present invention.

Claims (10)

1. Claims What is claimed is: 1. A detachable multi-blade skiving tool with staggered blades, characterized by comprising a tool substrate (I), a cutter blade set (2), and a pressing end cover (5), wherein the pressing end cover (5) is configured to fasten the cutter blade set (2) to the tool substrate (1) through a connecting piece; outer diameters and tooth profiles of cutter blades in the cutter blade set (2) respectively decrease in sequence in a direction from top to bottom; each of the cutter blades in the cutter blade set (2) comprises an identical number of teeth; gear teeth of adjacent two of the cutter blades are staggered; and an uppermost cutter blade in the cutter blade set (2) is configured for finish machining to obtain a tooth profile of a gear workpiece that meets a requirement, with the other cutter blades being configured for rough machining.
2. 2. The detachable multi-blade skiving tool with the staggered blades according to claim 1, characterized in that the cutter blade set (2) comprises a first cutter blade (21) and a plurality of second cutter blades (22), the first cutter blade (21) is located above the second cutter blades (22), a symmetrical center line of a tooth profile of each gear tooth of the plurality of second cutter blades (22) is deviated on an end surface from a symmetrical center line of a tooth profile of a respective gear tooth on the first cutter blade (21) by a predetermined angle, and adjacent two of the second cutter blades (22) are deviated in opposite directions
3. 3. The detachable multi-blade skiving tool with the staggered blades according to claim 1, characterized in that a calculation formula for an outer diameter du, of each of the second cutter blades (22) is cim=d10-(1-0.9*0.650-1))*2*If, wherein dc,0 represents an outer diameter of the first cutter blade (2 1), If represents a tooth groove depth of the gear workpiece to be machined, i represents a serial number of any one of the second cutter blades (22), ie [I,11, and i is a positive integer.
4. 4. The detachable multi-blade skiving tool with the staggered blades according to claim 3, characterized in that tooth profile parameters of the first cutter blade (21) are identical to tooth profile parameters of the second cutter blades (22) except for modulus, and a calculation formula for a modulus in, of each of the second cutter blades (22) is: tm=dallizt+2(h00+x,,o)], wherein.2.1 represents a tooth number of the tool, ha° represents an addendum coefficient, and x,,0 represents a profile shift coefficient.
5. 5. The detachable multi-blade skiving tool with the staggered blades according to claim 3, characterized in that a rake angle of each of the second cutter blades (22) is 00, and a relief angle of each of the second cutter blades (22) is 9° to 18°.
6. 6. The detachable multi-blade skiving tool with the staggered blades according to claim 3, characterized in that a thickness of the first cutter blade (21) is greater than a thickness of each of the second cutter blades (22).
7. 7. The detachable multi-blade skiving tool with the staggered blades according to claim 2, characterized in that a circular through hole (11) is provided on an end surface of the tool substrate (1), and a distance between a central axis of the circular through hole (11) and a central axis of the tool substrate (1) is Rp; a first positioning hole (211) is provided on an end surface of the first cutter blade (21), a center of the first positioning hole (211) is located on a symmetrical center line of a tooth profile of any cutter tooth, a diameter of the first positioning hole (211) is equal to a diameter of the circular through hole (11), and a distance between a central axis of the first positioning hole (211) and a central axis of the first cutter blade (21) is Rp; and a second positioning hole (221) is provided on an end surface of each of the second cutter blades (22), a center of the second positioning hole (221) is located on a symmetrical center line of a tooth profile of any cutter tooth, a distance between a central axis of the second positioning hole (221) and a central axis of a respective one of the second cutter blades (22) is Rp, and a diameter of the second positioning hole (221) is greater than the diameter of the first positioning hole (211).
8. 8. The detachable multi-blade skiving tool with the staggered blades according to claim 7, characterized in that a calculation formula for the diameter of the second positioning hole (221) and the diameter of the first positioning hole (211) is: D -D0+2/?*sinA, wherein Do represents the diameter of the first positioning hole (211), Di represents the diameter of the second positioning hole (221), and 0 represents a deviation angle of a symmetrical center line of a tooth profile of the first cutter blade (21) relative to a symmetrical center line of a tooth profile of the respective one of the second cutter blades (22) on the end surface.
9. 9. The detachable multi-blade slaving tool v\ith the staggered blades according to claim 8, characterized in that a calculation formula for 0 is 0=(tanai-tanao+ao-ai)*(;, wherein ao represents a pressure angle on the first cutter blade (21), the pressure angle is measured at an intersection of an involute tooth profile and a circular arc with a diameter d", and am -acos[(niez,*cosa,,)/d,,]; al represents a pressure angle on a second cutter blade (22) of the second cutter blades (22) being in contact with the first cutter blade (21), the pressure angle is measured at an intersection of an involute tooth profile and a circular arc with a diameter ac, and ai=acos[(mi*zi*cosan)aid; and j represents a setting coefficient of the deviation angle, and E[0.6,1].
10. 10. A method for assembling the detachable multi-blade skiving tool with the staggered blades according to claim 7, characterized by comprising: passing a location pin (3) through the second positioning hole (221) and the first positioning hole (211) in sequence, so that the location pin (3) extends into the circular through hole (11) to limit a positional relationship of the cutter blades in the cutter blade set (2) relative to the tool substrate (1), so that the cutter teeth of the cutter blades are in one-to-one correspondence; sequentially numbering the plurality of second cutter blades (22) in descending order of outer diameter, and rotating the odd-numbered second cutter blades (22) in turn, to make the corresponding second positioning holes (221) in contact with one side of the location pin (3) for positioning; rotating the even-numbered second cutter blades (22), to make the corresponding second positioning holes (221) in contact with the other side of the location pin (3) for positioning; and tightly pressing the pressing end cover (5) onto an end surface of the tool substrate (1) by a plurality of fastening screws (6), so that the cutter blade set (2) and the tool substrate (1) are coupled together.