A method of hard metal arc grinding, computer program and storage medium

Abstract

The present application relates to the technical field of grinding processing, and discloses a hard alloy cambered surface grinding method, which performs inner tangent cambered surface grinding on a workpiece by rotating a grinding wheel and feeding along a circular arc track; wherein the grinding wheel has a leading edge for grinding the workpiece, and the leading edge is an annular inner tangent arc groove; the bottom arc radius R of the inner tangent arc groove is greater than the top arc radius r of the inner tangent cambered surface, so that the top arc of the inner tangent cambered surface is always tangent to the bottom arc of the inner tangent arc groove during grinding; the present application has the advantages of keeping a large cutting depth during grinding, accelerating the grinding speed, reducing the number of grinding wheel dressing and consumption, prolonging the service life of the grinding wheel and saving costs.

Description

Technical Field

[0001] This invention relates to the field of grinding technology, and more specifically, to a method for grinding carbide arc surfaces. Background Technology

[0002] Currently, grinding is still the main method for machining cemented carbide parts. In actual machining, in addition to conventional grinding of internal holes, external circles and chamfers, grinding of curved surfaces often occurs.

[0003] Currently, most processes for grinding curved surfaces (r) employ the forming method, where the grinding wheel is dressed to fit the shape and size of the curved surface, and the workpiece is directly shaped using cutting or contact grinding methods. This machining method is simple to operate, and the precision of the forming grinding wheel determines the precision of the product; it can be implemented on ordinary grinding machines. However, because this method involves cutting or contact grinding, the feed rate is small, resulting in low machining efficiency. Furthermore, the high hardness of carbide materials leads to rapid grinding wheel wear. In addition, during forming grinding, the workpiece being ground by the grinding wheel exerts a reaction force on the grinding wheel, causing it to quickly and slowly revert to its original shape before grinding, resulting in low wheel retention. Summary of the Invention

[0004] The technical problem to be solved by this invention is to overcome the defects of small feed rate, fast grinding wheel consumption and low grinding wheel retention when machining the arc surface of cemented carbide workpieces by the form grinding method, and to propose a grinding method for the arc surface of cemented carbide.

[0005] The present invention solves the above problems through the following technical solution:

[0006] This invention provides a method for grinding the arc surface of cemented carbide, which involves rotating a grinding wheel and feeding along an arc trajectory to grind the workpiece on an inscribed arc surface.

[0007] The grinding wheel has a leading edge for grinding the workpiece, and the leading edge is an annular inscribed arc groove;

[0008] The bottom arc radius R of the inscribed groove is greater than the top arc radius r of the inscribed surface, so that the top arc of the inscribed surface is always tangent to the bottom arc of the inscribed groove during grinding.

[0009] Working principle and beneficial effects: By rotating the grinding wheel and feeding along an arc trajectory, the workpiece is ground on its internal tangent arc surface. During grinding, the top arc of the internal tangent arc surface is always internally tangent to the bottom arc of the internal tangent arc groove. The contact point between the grinding wheel and the workpiece, i.e., the internal tangent point, moves with the grinding process. When moving from one internal tangent point to the next, fresh, unworn, and effective abrasive grains are always added to the grinding. Compared with the form method, this increases the effective grinding area of ​​the grinding wheel and allows for a larger depth of cut to be maintained during grinding, thereby accelerating the grinding rate. Secondly, because the form method involves line or surface contact, the grinding wheel is easily grooved by the reaction force of the workpiece made of cemented carbide, increasing the wear on the grinding wheel. This invention provides a method for grinding carbide arc surfaces by feeding along an arc trajectory. The workpiece and the grinding wheel make point contact with each other on the inner tangent side. The grinding wheel experiences minimal reaction force from the workpiece. During the grinding process, the workpiece reaction continuously dresses the grinding wheel, making it less prone to grooves and deformation. The bottom arc of the inner tangent arc groove of the grinding wheel is uniformly dressed, increasing its radius, but it remains an arc. This reduces the number of dressing operations and the amount of grinding wheel consumption. In batch processing, it is only necessary to set the bottom arc radius compensation parameters, feed compensation parameters, compensation value update cycle, and life monitoring parameters of the inner tangent arc groove of the grinding wheel according to the amount of grinding wheel consumption. Multiple workpieces can be repeatedly processed without disassembling the grinding wheel for re-dressing, which can extend the service life of the grinding wheel and save costs.

[0010] According to some embodiments of the present invention, the top arc of the inscribed arc surface is a quarter circle arc.

[0011] According to some embodiments of the present invention, the bottom arc of the inscribed arc groove is a quarter circle arc.

[0012] According to some embodiments of the present invention, the arc trajectory is a quarter-circle arc.

[0013] According to some embodiments of the present invention, the front end face of the grinding wheel is perpendicular to the outer circumferential surface.

[0014] According to some embodiments of the present invention, the circular trajectory is planned by the following method:

[0015] a. Using the intersection of the front end face and the outer circumferential side of the grinding wheel on the XOY plane of the machine tool coordinate system as the tool position point O, obtain the bottom arc profile of the inner tangent arc groove on the XOY plane of the machine tool coordinate system as the grinding bottom arc AB, use the intersection of the grinding bottom arc AB and the front end face of the grinding wheel as the grinding start point A, and use the intersection of the grinding bottom arc AB and the outer circumferential surface of the grinding wheel as the grinding end point B;

[0016] b. Obtain the top arc profile of the inscribed arc surface on the XOY plane of the machine tool coordinate system, as the working top arc CD, and take the first endpoint of the working top arc CD as the machining start point C and the second endpoint of the working top arc CD as the machining end point D;

[0017] c. Move the grinding wheel so that the grinding starting point A contacts the machining starting point C, obtain the coordinates of the tool position point O in the machine tool coordinate system at this time as the programming origin coordinates, establish the programming coordinate system with the programming origin, and complete the tool setting;

[0018] d. Taking the contact point between the grinding bottom arc AB and the working top arc CD during internal grinding as point S, obtain the grinding wheel feed speed V, the distance Rs from point S to the grinding wheel center axis, the angle φ between point S and the X-axis of the machine tool coordinate system, and the linear velocity Vs of point S. Then, calculate the displacement of point S in the X-axis and Y-axis of the programming coordinate system during grinding using the following formulas:

[0019] e. Obtain the circular trajectory of the grinding wheel using the following formula:

[0020] Where x0 is the X-axis coordinate of the programming origin in the machine tool coordinate system, and y0 is the Y-axis coordinate of the programming origin in the machine tool coordinate system.

[0021] Working principle:

[0022] Before grinding, the grinding wheel is pre-dressed according to the top arc radius *r* of the inscribed arc surface to be machined on the workpiece, creating an inscribed arc groove with a bottom arc radius *R*, ensuring that the bottom arc radius *R* > the top arc radius *r*. During grinding, the grinding wheel is rotated and fed along an arc trajectory to grind the inscribed arc surface of the workpiece. The grinding wheel has a leading edge for grinding the workpiece, which is an annular inscribed arc groove. The bottom arc radius *R* of the inscribed arc groove is greater than the top arc radius *r* of the inscribed arc surface, ensuring that the top arc of the inscribed arc surface is always internally tangent to the bottom arc of the inscribed arc groove during grinding. The circular arc trajectory is achieved through planning, including obtaining the bottom arc profile of the inscribed arc groove as the grinding bottom arc AB, obtaining the top arc profile of the inscribed arc surface as the working top arc CD, the working top arc AB is always inscribed in the grinding bottom arc AB, which can be regarded as point contact during grinding, and the contact point is point S. The displacement of point S in the programming coordinate system X and Y axes during the grinding process is calculated by formula, thereby obtaining the circular arc trajectory points of the grinding wheel.

[0023] Based on the above working principle, compared with the forming method of grinding by line contact or surface contact, it has the following advantages:

[0024] The contact between the grinding wheel and the workpiece is point contact. During the grinding process of the grinding wheel's grinding bottom arc AB grinding the workpiece's working top arc CD, the working top arc CD is constantly internally tangent to the grinding bottom arc AB. The point of internal tangency, i.e. the grinding contact point, is point S. The position of point S on the grinding bottom arc AB changes from the grinding start point A to the grinding end point B, which corresponds exactly to the grinding from the working start point C to the working end point D of the working top arc CD. Since the position of point S on the grinding bottom arc AB moves with time, the abrasive grains participating in the grinding on the grinding bottom arc AB each time are all unworn and effective abrasive grains. Compared with the forming method, the effective grinding area of ​​the grinding wheel is increased, which can maintain a larger depth of cut during the grinding process to achieve the effect of accelerating the grinding rate.

[0025] Secondly, because the working top arc CD is constantly tangent to the grinding bottom arc AB during the grinding process, the reaction force from the workpiece at point S on the grinding wheel is small, which will cause wear on the abrasive grains on the entire grinding bottom arc AB. During the grinding process, the position of point S moves uniformly from the grinding start point A to the grinding end point B of the grinding bottom arc AB, which actually plays a similar role to dressing. The grinding wheel will not be grooved and is not easily deformed. The grinding bottom arc AB will be uniformly dressed and the radius will become larger, but it will always be a circular arc. This can reduce the number of additional dressing times and consumption of the grinding wheel. In batch processing, it is only necessary to set the bottom arc radius compensation parameters, feed compensation parameters, compensation value update cycle, and life monitoring parameters of the grinding wheel tangent arc groove according to the amount of grinding wheel consumption. Multiple workpieces can be processed repeatedly without disassembling the grinding wheel for dressing, which can extend the service life of the grinding wheel and save costs.

[0026] The present invention also provides a computer program that can run on a computer to perform the above-described method for grinding carbide arc surfaces.

[0027] The present invention also provides a computer storage medium storing computer program code, the computer program code being used to enable a computer to execute the above-described method for grinding a carbide arc surface. Attached Figure Description

[0028] The technical solution will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0029] Figure 1 A schematic diagram illustrating a method for grinding a carbide arc surface provided by the present invention;

[0030] Figure 2 A schematic diagram showing the relative positions of the grinding wheel and the workpiece on the machine tool in a cemented carbide arc surface grinding method provided by the present invention;

[0031] Figure 3 This is a schematic diagram illustrating the consumption of the grinding wheel according to the present invention.

[0032] Among them: 1. workpiece; 2. circular arc trajectory; 3. grinding wheel; 4. fixture; 5. rotating shaft. Detailed Implementation

[0033] The following detailed description, in conjunction with specific embodiments, further illustrates the above-described content of this invention. However, this should not be construed as limiting the scope of the invention to the following examples. Various substitutions or modifications made based on ordinary technical knowledge and conventional methods in the art without departing from the above-described technical concept should be included within the scope of this invention.

[0034] Example 1:

[0035] This embodiment of the invention provides a method for grinding carbide arc surfaces, such as... Figure 1 and Figure 2 As shown, the workpiece 1 is ground by rotating the grinding wheel 3 and feeding along the arc trajectory 2 to perform internal arc surface grinding;

[0036] The grinding wheel 3 has a leading edge for grinding the workpiece 1, and the leading edge is an annular inscribed arc groove;

[0037] The bottom arc radius R of the inscribed groove is greater than the top arc radius r of the inscribed surface, so that the top arc of the inscribed surface is always tangent to the bottom arc of the inscribed groove during grinding.

[0038] Working principle and beneficial effects: The grinding wheel 3 rotates via the spindle 5 and feeds along the arc trajectory 2, performing internal arc grinding on the workpiece 1 made of cemented carbide clamped on the machine tool fixture 4. During grinding, the top arc of the internal arc surface is always internally tangent to the bottom arc of the internal arc groove. The contact point between the grinding wheel 3 and the workpiece 1, i.e., the internal tangent point, moves with the grinding process. When moving from one internal tangent point to the next, brand new, unworn, effective abrasive grains are always added to the grinding process. Compared with the forming method, this increases the effective grinding area of ​​the grinding wheel 3, which can... Maintaining a large depth of cut during grinding accelerates the grinding rate. Secondly, because the forming method involves line or surface contact, the grinding wheel 3 is easily grooved by the reaction force of the carbide workpiece 1, increasing the dressing and wear of the grinding wheel 3. The carbide arc surface grinding method provided by this invention feeds along the arc trajectory 2, with the workpiece 1 and grinding wheel 3 making point contact internally. The grinding wheel 3 experiences less reaction force from the workpiece 1, and the workpiece 1's reaction force continuously dresses the grinding wheel 3 during the grinding process. This prevents the grinding wheel 3 from developing grooves and deforming due to grinding. Figure 3As shown, the bottom arc of the inner tangent groove of the grinding wheel 3 will be uniformly dressed and the radius will be increased, but it will always be a circular arc. This can reduce the number of dressing times and consumption of the grinding wheel 3. During batch processing, it is only necessary to set the bottom arc radius compensation parameters, feed compensation parameters, compensation value update cycle and life monitoring parameters of the inner tangent groove of the grinding wheel 3 according to the amount of grinding wheel 3 consumed. Multiple workpieces 1 can be processed repeatedly without disassembling the grinding wheel 3 for dressing. This can extend the service life of the grinding wheel 3 and save costs.

[0039] like Figures 1-3 As shown, the top arc of the inscribed arc surface is a quarter circle arc.

[0040] The bottom arc of the inscribed arc groove is a quarter circle.

[0041] The circular trajectory 2 is a quarter-circle arc.

[0042] The front end face of the grinding wheel 3 is perpendicular to the outer circumferential surface.

[0043] like Figure 1 As shown, the circular trajectory 2 is specifically planned using the following method:

[0044] a. Using the intersection of the front end face and the outer circumferential side surface of the grinding wheel 3 on the XOY plane of the machine tool coordinate system as the tool position point O, obtain the bottom arc profile of the inner tangent arc groove on the XOY plane of the machine tool coordinate system as the grinding bottom arc AB, use the intersection of the grinding bottom arc AB and the front end face of the grinding wheel 3 as the grinding start point A, and use the intersection of the grinding bottom arc AB and the outer circumferential surface of the grinding wheel 3 as the grinding end point B;

[0045] b. Obtain the top arc profile of the inscribed arc surface on the XOY plane of the machine tool coordinate system, as the working top arc CD, and take the first endpoint of the working top arc CD as the machining start point C and the second endpoint of the working top arc CD as the machining end point D;

[0046] c. Move the grinding wheel 3 to make the grinding starting point A contact with the machining starting point C, obtain the coordinates of the tool position point O in the machine tool coordinate system at this time as the programming origin coordinates, establish the programming coordinate system with the programming origin, and complete the tool setting;

[0047] d. Taking the contact point between the grinding bottom arc AB and the working top arc CD during internal grinding as point S, obtain the feed speed V of the grinding wheel 3, the distance Rs from point S to the central axis of the grinding wheel 3, the angle φ between point S and the X-axis of the machine tool coordinate system, and the linear velocity Vs of point S. Then, calculate the displacement of point S in the X-axis and Y-axis of the programming coordinate system during grinding using the following formulas:

[0048] e. Obtain the circular arc trajectory 2 of the grinding wheel 3 using the following formula:

[0049] Where x0 is the X-axis coordinate of the programming origin in the machine tool coordinate system, and y0 is the Y-axis coordinate of the programming origin in the machine tool coordinate system.

[0050] Working principle:

[0051] Before grinding, the grinding wheel 3 is pre-dressed according to the top arc radius r of the inscribed arc surface to be processed on the workpiece 1, creating an inscribed arc groove with a bottom arc radius R, ensuring that the bottom arc radius R > the top arc radius r. During grinding, the grinding wheel 3 is rotated and fed along the arc trajectory 2 to grind the inscribed arc surface of the workpiece 1. The grinding wheel 3 has a leading edge for grinding the workpiece 1, which is an annular inscribed arc groove. The bottom arc radius R of the inscribed arc groove is greater than the top arc radius r of the inscribed arc surface, ensuring that the top arc of the inscribed arc surface is always internally tangent to the bottom arc of the inscribed arc groove during grinding. The circular arc trajectory 2 is achieved through planning, including obtaining the bottom arc profile of the inscribed arc groove as the grinding bottom arc AB, obtaining the top arc profile of the inscribed arc surface as the working top arc CD, the working top arc AB is always inscribed in the grinding bottom arc AB, which can be regarded as point contact during grinding, and the contact point is point S. The displacement of point S in the programming coordinate system X and Y axes during the grinding process is calculated by formula, thereby obtaining the circular arc trajectory 2 point of the grinding wheel 3.

[0052] Based on the above working principle, compared with the forming method of grinding by line contact or surface contact, it has the following advantages:

[0053] The contact between grinding wheel 3 and workpiece 1 is point contact. During the grinding process of grinding wheel 3 grinding the bottom arc AB to the working top arc CD of workpiece 1, the working top arc CD is always internally tangent to the grinding bottom arc AB. The internal tangent point, i.e. the grinding contact point, is point S. The position of point S on the grinding bottom arc AB changes from the grinding start point A to the grinding end point B, which corresponds exactly to grinding from the working start point C to the working end point D of the working top arc CD. Since the position of point S on the grinding bottom arc AB moves with time, the abrasive grains participating in the grinding on the grinding bottom arc AB each time are effective abrasive grains that have not been worn. Compared with the forming method, the effective grinding area of ​​grinding wheel 3 is increased, and a larger depth of cut can be maintained during the grinding process to achieve the effect of accelerating the grinding rate.

[0054] Secondly, because the working top arc CD is constantly tangent to the grinding bottom arc AB during the grinding process, the reaction force from the workpiece 1 at point S on the grinding wheel 3 will cause wear on the abrasive grains along the entire grinding bottom arc AB. During the grinding process, the position of point S moves uniformly from the grinding start point A to the grinding end point B of the grinding bottom arc AB, effectively playing a similar role to dressing. The grinding wheel 3 will not be grooved and is not easily deformed. Figure 3The grinding bottom arc AB shown in the figure will be uniformly dressed and its radius will be increased, always remaining a circular arc. This can reduce the number of additional dressing times and consumption of the grinding wheel 3. During batch processing, it is only necessary to set the bottom arc radius compensation parameters, feed compensation parameters, compensation value update cycle, and life monitoring parameters of the grinding wheel 3 according to the amount of grinding wheel 3 consumed. This allows multiple workpieces 1 to be processed repeatedly without disassembling the grinding wheel 3 for re-dressing, which can extend the service life of the grinding wheel 3 and save costs.

[0055] Example 3:

[0056] This embodiment provides a computer program that can run on a computer to perform a carbide arc surface grinding method provided in this embodiment.

[0057] Example 4:

[0058] This embodiment provides a computer storage medium storing computer program code, which enables a computer to execute a carbide arc surface grinding method provided in Embodiment 1.

[0059] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications or equivalent changes made to the above embodiments based on the technical essence of the present invention shall fall within the protection scope of the present invention.

Claims

1. A method for grinding carbide arc surfaces, characterized in that, The workpiece is ground by rotating the grinding wheel and feeding along an arc trajectory; The grinding wheel has a leading edge for grinding the workpiece, and the leading edge is an annular inscribed arc groove; The bottom arc radius R of the inscribed groove is greater than the top arc radius r of the inscribed surface, so that the top arc of the inscribed surface is always internally tangent to the bottom arc of the inscribed groove during grinding. The circular trajectory is planned using the following method: a. Using the intersection of the front end face and the outer circumferential side of the grinding wheel on the XOY plane of the machine tool coordinate system as the tool position point O, obtain the bottom arc profile of the inner tangent arc groove on the XOY plane of the machine tool coordinate system as the grinding bottom arc AB, use the intersection of the grinding bottom arc AB and the front end face of the grinding wheel as the grinding start point A, and use the intersection of the grinding bottom arc AB and the outer circumferential surface of the grinding wheel as the grinding end point B; b. Obtain the top arc profile of the inscribed arc surface on the XOY plane of the machine tool coordinate system, as the working top arc CD, and take the first endpoint of the working top arc CD as the machining start point C and the second endpoint of the working top arc CD as the machining end point D; c. Move the grinding wheel so that the grinding starting point A contacts the machining starting point C, obtain the coordinates of the tool position point O in the machine tool coordinate system at this time as the programming origin coordinates, establish the programming coordinate system with the programming origin, and complete the tool setting; d. Taking the contact point between the grinding bottom arc AB and the working top arc CD during internal grinding as point S, obtain the grinding wheel feed speed V, the distance Rs from point S to the grinding wheel center axis, the angle Φ between point S and the X-axis of the machine tool coordinate system, and the linear velocity Vs of point S. Then, calculate the displacement of point S in the X-axis and Y-axis of the programming coordinate system during grinding using the following formulas: ; e. Obtain the circular trajectory of the grinding wheel using the following formula: ,in The programming origin is located at the X-axis coordinate of the machine tool coordinate system. The Y-axis coordinate of the programming origin in the machine tool coordinate system.

2. The method for grinding a carbide arc surface according to claim 1, characterized in that, The top arc of the inscribed arc surface is a quarter circle.

3. The method for grinding a carbide arc surface according to claim 1, characterized in that, The bottom arc of the inscribed arc groove is a quarter circle.

4. The method for grinding a carbide arc surface according to claim 1, characterized in that, The arc trajectory is a quarter-circle arc.

5. The method for grinding a carbide arc surface according to claim 1, characterized in that, The front end face of the grinding wheel is perpendicular to the outer circumferential surface.

6. A computer program, characterized in that: The program can run on a computer to perform a carbide arc surface grinding method according to any one of claims 1-5.

7. A computer storage medium, characterized in that: The system stores computer program code that enables a computer to perform a carbide arc surface grinding method as described in any one of claims 1-5.

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