A design method for a worm wheel slotted PCD turning tool and a PCD turning tool

Abstract

The present invention provides a design method for a worm grinding wheel slotting PCD turning tool and a PCD turning tool. According to the relationship between the grinding ratio and the lead, the integer division verification method is used to determine the number of worm grinding wheel heads; according to the left-handed or right-handed rotation of the processed gear and the worm grinding wheel, the left and right clearance angles of the slotting PCD turning tool are determined; based on the lead angle of the worm pitch circle, the left and right clearance angles of the PCD turning tool and the PCD turning tool tooth profile angle, as well as the angle of the PCD tool tip are calculated, and based on the module, the PCD tool tip arc and the depth of the PCD tool tip of the turning tool are determined; based on the spiral worm processing principle, the PCD turning tool slotting is completed. The present application utilizes the method to process the worm grinding wheel of gears with different parameters, and can not only be used for the early machinability verification of the worm grinding wheel, but also can be used as a drawing for pre-processing of the worm grinding wheel. The original PCD turning tool has a left and right clearance angle structure for the tool body to avoid interference between the turning tool and the grinding wheel during processing.

Description

Technical Field

[0001] The invention belongs to the technical field of grinding wheel turning tool processing, and in particular relates to a design method for a worm grinding wheel slotted PCD turning tool and a PCD turning tool. Background Art

[0002] With the development of new gearboxes such as new energy and AMT, the requirements for high speed and high torque of gears are further improved, and the rapid promotion of new gear grinding technology is imminent. At the same time, with the personalized customization of existing customers and diversified demands, high-speed gears are showing a trend of multi-variety and small-batch production.

[0003] In the prior art, slotted diamond rollers are used for worm wheel slotting. However, diamond rollers are expensive and have poor versatility. Different varieties require different diamond rollers, and a single diamond roller is not compatible with other varieties. Moreover, when designing the slotting of the diamond roller, the influence of the designed helix angle is not considered, which results in certain theoretical defects. Summary of the invention

[0004] In view of the problems existing in the prior art, the present invention provides a design method for a worm grinding wheel slotting PCD turning tool and a PCD turning tool, which solve the problems of high cost and poor versatility of worm grinding wheel slotting processing tools.

[0005] The present invention is achieved through the following technical solutions:

[0006] A design method for a worm wheel slotted PCD turning tool comprises the following steps:

[0007] According to the relationship between grinding ratio and lead, the number of worm wheel heads is determined using the integer verification method;

[0008] Determine the left and right clearance angles of the PCD tool for slotting according to whether the gear and worm wheel are rotated left or right;

[0009] The left and right clearance angles of the PCD turning tool, the tooth profile angle of the PCD turning tool, and the angle of the PCD tool tip are calculated based on the lead angle of the worm pitch circle, and the PCD tool tip arc and the depth of the PCD tool tip of the turning tool are determined based on the modulus;

[0010] PCD turning tool grooving is completed based on the helical worm machining principle.

[0011] Furthermore, the grinding ratio is the ratio of the number of teeth to the number of heads, and the grinding ratio is 8.5-11.

[0012] Furthermore, the number of heads in the integer divisibility verification method is a to-be-determined value, the number of heads is a positive integer N, and the ratio of the number of teeth to the number of heads cannot be an integer.

[0013] Furthermore, the lead is module*π*number of heads, and the lead ratio is less than 60.

[0014] Furthermore, when the worm wheel rotates counterclockwise, the left rear angle is greater than the right rear angle; when the worm wheel rotates clockwise, the right rear angle is greater than the left rear angle.

[0015] Furthermore, the calculation process of the left and right clearance angles of the PCD turning tool is as follows:

[0016] The grinding wheel tooth root height is the tooth root height ha0 of the machined part, ha0 = hf, hf is the tooth root height of the machined part;

[0017] Grinding wheel pitch circle diameter d0, d0 = da0 – 2·ha0, da0 is the grinding wheel tooth top circle diameter;

[0018] Grinding wheel pitch circle thread lead angle γz0, sinγz0=mn*N / d0, where mn is the normal module of the machined part and N is the number of heads;

[0019] With the same number of spiral threads, the larger the outer diameter of the worm wheel, the smaller the helix angle of the worm.

[0020] The maximum back angle of the cutter body is the thread lead angle of the grinding wheel indexing circle γz0+5°;

[0021] The small back angle of the tool body is 3°, which is an empirical value.

[0022] Furthermore, the tooth profile angle of the PCD turning tool is twice the normal pressure angle of the pitch circle of the machined part;

[0023] The included angle of the PCD tool tip is twice the normal pressure angle of the pitch circle of the machined part.

[0024] Furthermore, if the module is 1-3 mm, the arc of the PCD tool tip is R1, if the module is 4-6 mm, the arc of the PCD tool tip is R1.6, and if the module is 6-8 mm, the arc of the PCD tool tip is R3.

[0025] Furthermore, the depth of the PCD tool tip is:

[0026] Grinding wheel tooth top height ha0, ha0 = hf, where hf is the tooth root height of the machined part;

[0027] Grinding wheel tooth root height hf0, hf0 = ha + c'·mn, where ha is the tooth top height of the machined part, c' is the radial clearance coefficient, and mn is the normal module of the machined part;

[0028] The total height of the grinding wheel teeth is h0, h0=ha0+hf0, and the total height of the grinding wheel teeth h0 is the depth of the PCD tool tip of the turning tool.

[0029] A worm wheel slotted PCD turning tool, a PCD turning tool adopted in a design method for a worm wheel slotted PCD turning tool, comprising a tool body and a PCD tool tip fixedly arranged at the end of the tool body;

[0030] The knife body is a rectangular structure, the end of which is a V-shaped structure, and one side is provided with a groove, and a PCD knife tip is fixedly arranged in the groove.

[0031] Compared with the prior art, the present invention has the following beneficial technical effects:

[0032] The present invention provides a design method for a worm grinding wheel slotting PCD turning tool and a PCD turning tool. According to the relationship between the grinding ratio and the lead, the integer division verification method is used to determine the number of worm grinding wheel heads; according to the left-handed or right-handed rotation of the processed gear and the worm grinding wheel, the left and right clearance angles of the slotting PCD turning tool are determined; based on the lead angle of the worm pitch circle, the left and right clearance angles of the PCD turning tool and the PCD turning tool tooth profile angle, as well as the angle of the PCD tool tip are calculated, and based on the module, the PCD tool tip arc and the depth of the PCD tool tip of the turning tool are determined; based on the spiral worm processing principle, the PCD turning tool slotting is completed. The present application utilizes the method to process the worm grinding wheel of gears with different parameters, and can not only be used for the early machinability verification of the worm grinding wheel, but also can be used as a drawing for pre-processing of the worm grinding wheel. The original PCD turning tool has a left and right clearance angle structure for the tool body to avoid interference between the turning tool and the grinding wheel during processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 A flow chart of a method for designing a worm wheel slotted PCD turning tool according to the present invention;

[0034] Figure 2 This is a front view of the PCD turning tool structure of the present invention;

[0035] Figure 3 It is a side view of the PCD turning tool structure of the present invention;

[0036] Figure 4 It is a schematic diagram of the knife body structure of the present invention;

[0037] Figure 5 This is a schematic diagram of the PCD tool tip structure of the present invention.

[0038] In the figure: 1. tool body; 2. PCD tool tip; 3. groove. DETAILED DESCRIPTION

[0039] The present invention is further described in detail below in conjunction with specific embodiments, which are intended to explain the present invention rather than to limit it.

[0040] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments 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 creative work should fall within the scope of protection of the present invention.

[0041] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0042] The present invention provides a design method for a worm grinding wheel slotted PCD turning tool, comprising the following steps:

[0043] According to the relationship between grinding ratio and lead, the number of worm wheel heads is determined using the integer verification method;

[0044] Determine the left and right clearance angles of the PCD tool for slotting according to whether the gear and worm wheel are rotated left or right;

[0045] The left and right clearance angles of the PCD turning tool, the tooth profile angle of the PCD turning tool, and the angle of the PCD tool tip are calculated based on the lead angle of the worm pitch circle, and the PCD tool tip arc and the depth of the PCD tool tip of the turning tool are determined based on the modulus;

[0046] PCD turning tool grooving is completed based on the helical worm machining principle.

[0047] Preferably, the grinding ratio is the ratio of the number of teeth to the number of heads, and the grinding ratio is 8.5-11.

[0048] Preferably, the number of heads in the integer divisibility verification method is a to-be-determined value, the number of heads is a positive integer N, and the ratio of the number of teeth to the number of heads cannot be an integer.

[0049] Preferably, the lead is module*π*number of heads, and the lead ratio is less than 60.

[0050] Preferably, when the worm wheel rotates counterclockwise, the left rear angle is greater than the right rear angle; when the worm wheel rotates clockwise, the right rear angle is greater than the left rear angle.

[0051] Preferably, the calculation process of the left and right clearance angles of the PCD turning tool is as follows:

[0052] The grinding wheel tooth root height is the tooth root height ha0 of the machined part, ha0 = hf, hf is the tooth root height of the machined part;

[0053] Grinding wheel pitch circle diameter d0, d0 = da0 – 2·ha0, da0 is the grinding wheel tooth top circle diameter;

[0054] Grinding wheel pitch circle thread lead angle γz0, sinγz0=mn*N / d0, where mn is the normal module of the machined part and N is the number of heads;

[0055] With the same number of spiral threads, the larger the outer diameter of the worm wheel, the smaller the helix angle of the worm.

[0056] The maximum back angle of the cutter body is the thread lead angle of the grinding wheel indexing circle γz0+5°;

[0057] The small back angle of the tool body is 3°, which is an empirical value commonly used by technicians in this field.

[0058] Preferably, the tooth profile angle of the PCD turning tool is twice the normal pressure angle of the pitch circle of the machined part;

[0059] The included angle of the PCD tool tip is twice the normal pressure angle of the pitch circle of the machined part.

[0060] Preferably, if the module is 1-3 mm, the arc of the PCD tool tip is R1, if the module is 4-6 mm, the arc of the PCD tool tip is R1.6, and if the module is 6-8 mm, the arc of the PCD tool tip is R3.

[0061] Preferably, the depth of the PCD tool tip is:

[0062] Grinding wheel tooth top height ha0, ha0 = hf, where hf is the tooth root height of the machined part;

[0063] Grinding wheel tooth root height hf0, hf0 = ha + c'·mn, where ha is the tooth top height of the machined part, c' is the radial clearance coefficient, and mn is the normal module of the machined part;

[0064] The total height of the grinding wheel teeth is h0, h0=ha0+hf0, and the total height of the grinding wheel teeth h0 is the depth of the PCD tool tip of the turning tool.

[0065] The invention provides a worm grinding wheel slotted PCD turning tool, which is obtained based on a worm grinding wheel slotted PCD turning tool design method.

[0066] The present invention provides a preferred embodiment: the parameters of the processed gear are: normal module (basic parameter of the gear) mn=4.118, pressure angle (basic parameter of the gear) α=20°, number of teeth (basic parameter of the gear) Z=25, left-handed hf=5.474;

[0067] The specifications of the worm grinding wheel (outer diameter x length x inner hole) are φ150x200xφ50.8mm;

[0068] Calculation 1. Grinding ratio = Z / N = 25 / 3 = 8.33, which is between 8 and 11.

[0069] Calculation 2: Lead = m*π*N = 4.118X3.14X3 = 38.79, which is less than 60.

[0070] Calculation 3, divisibility = Z / N = 25 / 3 = 8.3, which is not divisible.

[0071] The number of worm grinding wheel heads is generally N=1 / 2 / 3 / 4 / 5 / 6. Using the substitution method, conditions 1, 2 and 3 must be met. Based on the fact that the number of heads in the integer verification method is a pending value, the number of heads is a positive integer N, and the ratio of the number of teeth to the number of heads cannot be an integer, N=3 is selected.

[0072] Step 2: The processed parts rotate counterclockwise, the worm grinding wheel rotates counterclockwise, and the left rear angle is greater than the right rear angle.

[0073] Step 3: Grinding wheel tooth top height ha0, ha0=hf=5.474mm;

[0074] Grinding wheel pitch circle diameter d0, d0 = da0 – 2 ha0 = 150-2x5.474 = 99.052;

[0075] Grinding wheel indexing circle thread lead angle γz0, sinγz0=mn·N / d0;

[0076] γz0=arcsin(mn·N / d0)=arcsin(4.118x3 / 99.052)=7.16°;

[0077] The maximum back angle of the tool body = γz0 = arcsin (7x6 / 99.052) = 25°, according to the limit values ​​mn = 7, N = 6.

[0078] The small back angle of the cutter body = 3°;

[0079] Step 4: Cutter body tooth profile angle = 2* normal pressure angle of the pitch circle of the machined part = 2x20° = 40°;

[0080] Step 5: The angle of the PCD tool tip = 2*the normal pressure angle of the pitch circle of the machined part = 2x20° = 40°;

[0081] Step 6: Determine the PCD tool tip radius, modulus 4-6mm, select R1.6;

[0082] Step 7: Determine the depth of the PCD tool tip: H = h0 + 6mm, 6 is the margin.

[0083] h0=ha0+hf0=hf+ha+c′·mn=5.474+5.278+0.2X4.118=11.57mm

[0084] H=h0+6mm=11.57+6=18mm

[0085] The present invention provides a worm wheel slotted PCD turning tool, specifically: a PCD turning tool used in a worm wheel slotted PCD turning tool design method, such as Figure 2 and Figure 3 As shown, it comprises a knife body 1 and a PCD knife tip 2 fixedly arranged at the end of the knife body 1; the knife body 1 is a rectangular structure, the end of which is a V-shaped structure, and a groove 3 is arranged on one side, and the PCD knife tip 2 is fixedly arranged in the groove 3; further, as Figure 4 and Figure 5 As shown, the V-shaped structure at the end of the tool body 1 is asymmetrical, the left rear angle of the tool body is 25°, the right rear angle of the tool body is 3°, the tooth angle of the tool body of the V-shaped structure is 40°±6′, the PCD tool tip 2 is an isosceles triangle shape, the angle of the PCD tool tip 2 is 40°±6′, and the arc of the PCD tool tip 2 is R1.6. The depth of the PCD tool tip of the turning tool is determined to be 18mm, and the thickness of the PCD tool tip 2 is 3mm. Specifically, the worm wheel slotting PCD turning tool adopts the welding process of the tool body 1 and the PCD tool tip 2 to be firm and without false welding.

[0086] This PCD turning tool and design method can achieve high-precision and high-efficiency worm wheel slotting processing and reduce tool costs.

[0087] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A design method for a worm wheel slotted PCD turning tool, characterized in that: The following steps are involved: According to the relationship between grinding ratio and lead, the number of worm wheel heads is determined using the integer verification method; The grinding ratio is the ratio of the number of teeth to the number of heads of the machined part, and the grinding ratio is 8.5-11; the number of heads in the integer verification method is a pending value, the number of heads is a positive integer N, and the ratio of the number of teeth to the number of heads cannot be an integer; the lead is the module*π*number of heads, and the lead is less than 60mm; Determine the left and right clearance angles of the PCD tool for slotting according to whether the gear being processed and the worm wheel are left-handed or right-handed; Based on the thread lead angle of the grinding wheel pitch circle, the specific values ​​of the left and right clearance angles of the PCD turning tool, the pressure angle on the gear pitch circle, and the angle of the PCD tool tip are calculated. Based on the modulus, the PCD tool tip arc and the depth of the PCD tool tip of the turning tool are determined. The specific numerical calculation process of the left and right clearance angles of the PCD turning tool is as follows: The grinding wheel tooth top height ha0 is the tooth root height hf of the machined part; Grinding wheel pitch circle diameter d0, d0=da0–2·ha0, da0 is the grinding wheel tooth top circle diameter; Grinding wheel pitch circle thread lead angle γz0, sinγz0=mn*N / d0, where mn is the normal module of the machined part and N is the number of heads; With the same number of worm wheel heads, the larger the outer diameter of the worm wheel, the smaller the helix angle of the worm. When the worm wheel rotates counterclockwise, the left rear angle is greater than the right rear angle; The left rear angle of the PCD turning tool is the thread lead angle of the grinding wheel indexing circle γz0+5°; The right rear angle of the PCD turning tool is 3°, which is an empirical value; When the worm wheel rotates right, the right rear angle is greater than the left rear angle; The right rear angle of the PCD turning tool is the thread lead angle of the grinding wheel indexing circle γz0+5°; The left rear angle of the PCD turning tool is 3°, which is an empirical value; If the modulus is 1-3mm, the PCD tool tip arc is R1, if the modulus is 4-6mm, the PCD tool tip arc is R1.6, if the modulus is 6-8mm, the PCD tool tip arc is R3; PCD turning tool grooving is completed based on the helical worm machining principle.

2. According to claim 1, a method for designing a worm wheel slotting PCD turning tool is characterized in that: The depth of the PCD tool tip is: Grinding wheel tooth top height ha0, ha0=hf, where hf is the tooth root height of the machined part; Grinding wheel tooth root height hf0, hf0=ha+c′·mn, where ha is the tooth top height of the machined part, c′ is the radial clearance coefficient, and mn is the normal module of the machined part; The total height of the grinding wheel teeth is h0, h0=ha0+hf0, and the total height of the grinding wheel teeth h0 is the depth of the PCD tool tip of the turning tool.

3. A worm wheel slotting PCD turning tool, characterized in that: A PCD turning tool used in a method for designing a worm wheel slotting PCD turning tool as described in any one of claims 1 to 2 comprises a tool body (1) and a PCD tool tip (2) fixedly arranged at the end of the tool body (1); The knife body (1) is a rectangular structure, the end of which is a V-shaped structure, and one side is provided with a groove (3), and a PCD knife tip (2) is fixedly arranged in the groove (3).

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