JP4443823B2 - Grinding machine machining simulation system, grinding machine machining simulation method, and grinding machine machining simulation program - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a processing simulation system for a grinding apparatus, a processing simulation method for a grinding apparatus, and a processing simulation program for a grinding apparatus. The present invention relates to a simulation system, a machining simulation method for a grinding apparatus, and a machining simulation program for a grinding apparatus.
[0002]
[Prior art]
In general, in a double-head grinding machine in a grinding machine, when the grinding wheel is replaced with a new grinding wheel of the same type or with a grinding wheel of a different shape, the grinding wheel diameter, the width of the grinding operation surface (grinding the grinding wheel workpiece) Parts to be machined), physical properties such as Young's modulus of the grinding wheel, size of the abrasive grains, tilt of the grinding spindle relative to the grinding surface of the workpiece, tilt of the grinding wheel relative to the grinding spindle, grinding wheel rotation speed, grinding wheel cutting speed, etc. The state of the ground surface of the workpiece changes. Therefore, in the double-head grinding machine, the grinding conditions such as the inclination of the grinding spindle to the grinding surface of the workpiece, the inclination of the grinding wheel with respect to the grinding spindle, the rotation speed of the grinding wheel, and the cutting speed of the grinding wheel are optimal in order to precisely machine the workpiece after changing the grinding wheel It is necessary to make it.
[0003]
In conventional double-head grinding machines, skilled workers determine grinding conditions based on their own intuition and experience, and use several tens of workpieces for workpiece grinding and evaluation of the ground surface after grinding. Was repeated.
[0004]
Note that in a CMP (Chemical Mechanical Polishing) apparatus that flattens a step by polishing, there is a technique for predicting a shape after polishing by simulation. (For example, refer to Patent Document 1).
[0005]
[Patent Document 1]
JP 11-126765 A
[0006]
[Problems to be solved by the invention]
However, in the conventional double-head grinding apparatus as described above, the grinding condition after the wheel replacement is optimized based on the operator's intuition and experience. Cannot be sufficiently performed, the state of the ground surface of the ground workpiece is deteriorated, and the processing accuracy of the workpiece depends on the skill level of the operator.
[0007]
Furthermore, in the method based on the intuition and experience of the operator, there is a problem that it is necessary to grind and evaluate many workpieces, and it takes a long time to optimize the grinding conditions.
[0008]
In addition, a double-head grinding apparatus that simultaneously polishes both surfaces of a workpiece has a different basic configuration from the CMP apparatus, and thus the simulation technique of the CMP apparatus cannot be simply used for the simulation of the double-head grinding apparatus.
[0009]
Therefore, the present invention has been made in view of the above circumstances, and can be easily obtained in a short time using a small number of workpieces without depending on the skill level of the worker, without depending on the skill level of the operator. It is an object of the present invention to provide a grinding machine machining simulation system, a grinding machine machining simulation method, and a grinding machine machining simulation program.
[0010]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present invention is characterized by the following measures.
[0011]
  According to one aspect of the present invention, based on the change in grinding resistance with time and the relationship between the cutting speed and the grinding resistance.By the following formulaDesiredWorkGrinding amountduBased onSaidThere is provided a machining simulation system for a grinding apparatus, characterized by having a computing means for computing the state of a ground surface of a workpiece.
  du = ασ ⁿ dh
However, (sigma) is the grinding resistance which generate | occur | produces when the said workpiece | work and a grindstone contact, (alpha) and n are the parameters which show the grinding capability of the said grindstone, and dh is the distance which the said grindstone moved on the grinding surface of the said workpiece | work.
[0012]
Here, an expression for obtaining the grinding amount of the work necessary for obtaining the state of the ground surface of the work by calculation will be described.
[0013]
du = ασⁿdh (1)
The above equation is an equation for obtaining the grinding amount of the workpiece. In the above formula, du is the grinding amount of the workpiece, σ is the grinding resistance generated by the contact between the workpiece and the grindstone, dh is the distance that the grindstone has moved on the grinding surface of the workpiece, and α and n are the grindstone. The parameters indicating the grinding ability are shown respectively.
[0014]
In the above invention, α and n shown in the above formulas necessary for obtaining the grinding amount are obtained from the time change of the grinding resistance, and n is obtained from the relationship between the cutting speed and the grinding resistance. As described above, by calculating the grinding amount based on the two processing data of α and n, it is possible to easily obtain the state of the ground surface of the workpiece without actually grinding the workpiece. Therefore, the workpiece evaluation and the grinding conditions can be optimized in a short time without depending on the skill level of the operator.
[0015]
  Also beforeThe time variation of grinding resistance is obtained based on actual machining data obtained by grinding the workpiece.May be.
[0016]
  ThisThe time change of the grinding resistance is obtained based on actual machining data obtained by grinding the workpiece. Therefore, the time change of the grinding resistance obtained from the actual machining data is used for the calculation of the state of the grinding surface of the workpiece. As a result, it is possible to improve the accuracy of the state of the ground surface of the workpiece obtained by calculation.
[0017]
  Also,The relationship between the cutting speed and the grinding resistance is obtained based on actual machining data obtained by grinding the workpiece.You may choose.
[0018]
  As a result,For the calculation of the state of the grinding surface of the workpiece, the relationship between the cutting speed obtained from the actual machining data and the grinding resistance is used. As a result, it is possible to improve the accuracy of the state of the ground surface of the workpiece obtained by calculation.
[0019]
Also,A processing simulation system for a grinding apparatus according to claim 1.InCommunication means is provided for receiving data relating to the time variation of the grinding resistance generated by the grinding apparatus.You may choose.
[0020]
  By providing such communication means,Since the communication means can receive the data regarding the time change of the grinding resistance transmitted from the grinding apparatus, the data regarding the time change of the grinding resistance can be updated. As a result, the state of the grinding device that changes with time is reflected in the data relating to the time change of the grinding resistance, and the accuracy of the state of the ground surface of the workpiece obtained by calculation can be improved.
[0025]
  According to another aspect of the present invention, obtaining a first data that is a change in grinding resistance with time,
  Obtaining second data that is a relationship between the cutting speed and the grinding resistance;
  Based on the first data and the second dataFrom the following formulaDesiredWorkGrinding amountduBased onSaidAnd a step of obtaining the state of the ground surface of the workpiece by calculation.
du = ασ ⁿ dh
However, (sigma) is the grinding resistance which generate | occur | produces when the said workpiece | work and a grindstone contact, (alpha) and n are the parameters which show the grinding capability of the said grindstone, and dh is the distance which the said grindstone moved on the grinding surface of the said workpiece | work.
[0026]
According to the above invention, α and n shown in the equation (1) necessary for obtaining the above grinding amount are obtained from the first data which is the time change of the grinding resistance, and the cutting speed, the grinding resistance, N is obtained from the second data which is As described above, by calculating the grinding amount by the calculation means based on the two data of α and n, the state of the ground surface of the workpiece can be easily obtained without actually grinding the workpiece. Therefore, the workpiece evaluation and the grinding conditions can be optimized in a short time without depending on the skill level of the operator.
[0027]
  Also,The first data is obtained based on actual machining data obtained by grinding the workpiece.You may choose.
[0028]
  As described above, the first data is obtained based on the actual machining data obtained by grinding the workpiece.The first data obtained from the actual machining data is used in the calculation of the state of the grinding surface of the workpiece. As a result, it is possible to improve the accuracy of the state of the ground surface of the workpiece obtained by calculation.
[0029]
  Also beforeThe second data is obtained based on actual machining data obtained by grinding the workpiece.You may choose.
[0030]
  Thus, by obtaining the second data based on the actual machining data obtained by grinding the workpiece,The second data obtained from the actual machining data is used for the calculation of the state of the grinding surface of the workpiece. As a result, it is possible to improve the accuracy of the state of the ground surface of the workpiece obtained by calculation.
[0033]
  According to another aspect of the invention, a computer includes:
  1st data which is time change of grinding resistance,
  Based on the second data, which is the relationship between cutting speed and grinding resistanceFrom the following formulaDesiredWorkGrinding amountduBased onThe workA processing simulation program of a grinding apparatus for calculating the state of the ground surface is provided.
  du = ασ ⁿ dh
However, (sigma) is the grinding resistance which generate | occur | produces when the said workpiece | work and a grindstone contact, (alpha) and n are the parameters which show the grinding capability of the said grindstone, and dh is the distance which the said grindstone moved on the grinding surface of the said workpiece | work.
[0034]
According to the above invention, α and n shown in the equation (1) necessary for obtaining the above grinding amount are obtained from the first data which is the time change of the grinding resistance, and the cutting speed, the grinding resistance, N is obtained from the second data which is As described above, by calculating the grinding amount by the calculation means based on the two data of α and n, the state of the ground surface of the workpiece can be easily obtained without actually grinding the workpiece. Therefore, the workpiece evaluation and the grinding conditions can be optimized in a short time without depending on the skill level of the operator.
[0035]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described with reference to the drawings.
[0036]
(First embodiment)
In this embodiment, a double-head grinding device will be described as an example of a grinding device.
[0037]
FIG. 1 is a system configuration diagram of a machining simulation system according to the first embodiment of the present invention. In the present embodiment, as will be described in detail later, a machining simulation is performed based on actual machining data obtained from the double-head grinding apparatus 20.
[0038]
The machining simulation system of the double-head grinding apparatus 20 is implemented using the computer 10 (see FIG. 1). The processing simulation system of the double-head grinding device 20 is implemented based on data generated in advance by the double-head grinding device 20.
[0039]
In the following description, the configuration of the double-head grinding apparatus 20 will be described first, and then the configuration of the simulation system will be described.
[0040]
FIG. 2 is a view showing a general double-head grinding apparatus. As shown in the figure, the double-head grinding device 20 is roughly constituted by grinding devices 40 a and 40 b and a work holding device 41.
[0041]
Two grinding machines 40a and 40b are arranged so that the same configuration faces each other across the grinding position of the workpiece 42. Since the grinding devices 40a and 40b disposed across the grinding position of the workpiece 42 have the same configuration in this way, with respect to FIG. The grinding apparatus located in the lower part of the figure will be described by adding the symbol b. In the following, the side added with the symbol a is called the master side, and the side added with the symbol b is called the slave side.
[0042]
The grinding devices 40a and 40b include grindstones 35a and 35b, grinding spindles 36a and 36b, driving devices 38a and 38b, and moving devices 37a and 37b. The grindstones 35a and 35b are annular grindstones, and are configured such that the grindstone is fixed in a cup shape (portion facing the workpiece 42). In the grindstones 35a and 35b, flat grinding operation surfaces 34a and 34b are formed on the cup-like open end face (surface on which the abrasive grains are fixed).
[0043]
The grindstones 35a and 35b having the above-described configuration are integrally disposed at one end of the grinding spindles 36a and 36b. Drive devices 38a and 38b are disposed at the other ends of the grinding spindles 36a and 36b. The driving devices 38a and 38b are for driving the grinding spindles 36a and 36b to rotate. Therefore, the grindstones 35a and 35b are rotated by the driving devices 38a and 38b via the grinding spindles 36a and 36b.
[0044]
The driving devices 38a and 38b are configured to be moved by the moving devices 37a and 37b. The moving devices 37a and 37b move the driving devices 38a and 38b in the directions of arrows Y1 and Y2 in the figure. Therefore, when the moving devices 37a and 37b move the drive devices 38a and 38b away from the grinding position, the grindstones 35a and 35b are separated as shown in FIG. Conversely, the moving devices 37a and 37b move the driving devices 38a and 38b closer to the grinding position from the position shown in FIG. 2, so that the double-head grinding device 20 shown on the right side in FIG. The grindstones 35a and 35b are in a state of sandwiching the workpiece 42.
[0045]
Next, the workpiece holding device 41 will be described. In general, the work holding device 41 includes a work holder frame 31, a clamp arm 43, an arm opening / closing rotary shaft 44, rollers 33A, 33B, 33C with V grooves, a drive motor 30, and the like.
[0046]
The work holder frame 31 is provided with a clamp arm 43, an arm opening / closing rotary shaft 44, V-grooved rollers 33 </ b> A, 33 </ b> B, 33 </ b> C, and a drive motor 30. A clamp arm 43 is arranged at one upper end of the work holder frame 31 in a state in which the clamp arm 43 can swing in the directions of the arrows X1 and X2 around the arm closing / opening rotating shaft 44. It is installed. The clamp arm 43 is integrally provided with a V-grooved roller 33 </ b> C for rotating and holding the work 42. When the workpiece 42 is attached / detached, the clamp arm 43 shown in FIG. 2 is moved from the closed state to the opened state (not shown) by moving the clamp arm 43 in the directions of arrows X1 and X2. The work 42 can be attached and detached. The clamp arm 43 moves in the directions of arrows X1 and X2 in FIG. 2 after the work 42 is attached and detached, and is closed as shown in FIG. 2, and the V-grooved roller 33C comes into contact with the work 42, 42 is rotatably held by a V-grooved roller 33C and V-grooved rollers 33A and 33B.
[0047]
A drive motor 30 is disposed on the upper left side of the work holder frame 31 in the drawing, and a V-grooved roller 33 </ b> A is disposed below the drive motor 30. A V-grooved roller 33B is disposed on the work holder frame 31 between the V-grooved roller 33A and the V-grooved roller 33C shown in FIG.
[0048]
In the double-head grinding apparatus 20 as described above, it is necessary to input grinding conditions as shown below when performing actual machining.
[0049]
Next, with reference to FIG. 3, the grinding conditions used for the processing simulation of the double-head grinding apparatus 20 will be described. FIG. 3 is a diagram showing grinding conditions used for processing simulation of the double-head grinding apparatus.
[0050]
The grinding conditions used for the simulation of the shape and thickness distribution of the grinding surface of the workpiece include the cutting speed of the grinding wheel, the inclination of the grinding spindle relative to the workpiece, the inclination of the grinding wheel relative to the grinding spindle, the rotational speed of the workpiece, Diameter, grinding wheel rotation speed, grinding wheel diameter, grinding wheel width, grinding wheel Young's modulus, grinding wheel rotation direction, workpiece rotation direction, grinding time, spark-out time, external force (In the following description, the above-described grinding conditions are collectively referred to as grinding conditions 50).
[0051]
As shown in FIG. 3, the cutting speed of the grindstone is the moving speed of the grindstones 35 a and 35 b that move in the Y1 and Y2 directions toward the workpiece 42. The inclination of the grinding spindle relative to the workpiece 42 is an inclination θ1 formed by the center line 48 of the workpiece 42 in the Y1 and Y2 directions and the center line 49 of the grinding spindle 36a in the Y1 and Y2 directions.
[0052]
The inclination of the grindstone with respect to the grinding spindle is an inclination θ2 formed by the center line 53 of the grinding spindle 36b in the Y1 and Y2 directions and the center line 52 of the grinding stone 35b in the Y1 and Y2 directions. When grinding is performed in a state where the inclination θ2 is large, the grinding spindle 36b and the grindstone 35b rotate in a state where both of them are swung, which affects the grinding surface of the workpiece 42. Note that the inclination of the grindstone with respect to the grinding spindle is taken as an example representing the runout of the grindstone 35b.
[0053]
The rotation speed of the work is a speed at which the work 42 rotates. The rotation speed of the grindstone is the speed at which the grindstones 35a and 35b rotate. The diameter of the grindstone is the diameter 55 shown in the figure, and the width of the grinding operation surface of the grindstone is L shown in the figure.
[0054]
The spark-out time is a time for grinding the workpiece in this state by stopping the cutting speed of the grindstone while rotating the grindstone and the workpiece at the end of the grinding of the workpiece 42. The external force is a force that affects the grinding of the workpiece 42 except for the above grinding conditions.
[0055]
By performing the simulation using the grinding condition 50 having information related to grinding as described above, the shape of the grinding surface of the workpiece 42 obtained by actually grinding the workpiece 42 and the workpiece 42 obtained from the simulation are obtained. The difference from the shape of the ground surface of the grinding becomes small, and a highly accurate simulation can be performed. By performing the simulation, the thickness of the workpiece 42 can be obtained in addition to the shape of the grinding surface of the workpiece 42.
[0056]
Next, with reference to FIG. 4, the structure of the computer 10 which performs the process simulation of a double-head grinding apparatus is demonstrated. FIG. 4 is a diagram showing an internal configuration of the computer shown in FIG.
[0057]
The computer 10 includes a CPU 60, an input device 61, a ROM 62, a RAM 63, a CLK 64, a first database 65, a second database 66, and an output device 67.
[0058]
The CPU 60 reads machining simulation software stored in the RAM 63 and executes machining simulation processing described later. The input device 61 is specifically a keyboard or the like, and in this embodiment, a floppy (registered trademark) disk device (FDD) is also used as the input device. The input device 61 is for inputting data from the outside to the computer 10.
[0059]
The ROM 62 stores a predetermined OS, and the RAM 63 stores machining simulation software for obtaining the shape and thickness distribution of the grinding surface of the workpiece 42. CLK64 controls the operation timing of the CPU 60, ROM 62, and RAM 63.
[0060]
The first database 65 is for storing the grinding resistance time change data input from the input device 61 and the grinding resistance data with respect to the cutting speed of the grindstone. The second database 66 is for storing data on the surface shape and thickness distribution of the workpiece 42 calculated by the CPU 60.
[0061]
The output device 67 is a CRT, a printer, or the like, and is for displaying the result calculated by the CPU 60.
[0062]
Next, with reference to FIG. 5, the process simulation process for calculating | requiring the shape of the grinding surface of the workpiece | work 42 in a present Example is demonstrated. FIG. 5 is a flowchart showing a machining simulation process for obtaining the shape of the ground surface of the workpiece.
[0063]
In addition, although the main component force and the back component stress can be used as the grinding resistance necessary for obtaining the grinding amount, in this embodiment, the following processing simulation of an example in which the back component stress is used for the grinding resistance is described below. Give an explanation.
[0064]
First, prior to the description of the specific processing of the processing simulation, calculation processing of a grinding amount of a cell 95, which will be described later, necessary for performing processing simulation of the state of the ground surface of the workpiece will be described using the following formula. Note that the cell 95 is a cell in one region obtained by dividing the grinding surface of the workpiece 42 into a plurality of cells as will be described later.
[0065]
du_M= Α_Mσ_M ^nMdhβ (t) (2)
The above equation (2) is an equation for obtaining the grinding amount du of the cell 95,_MIndicates the master side grinding device 40a. In the case of the slave side grinding device 40b,_MPart of_SChanges to. The arithmetic processing for obtaining the grinding amount du of the cell 95 is performed for each of the master side grinding device 40a and the slave side grinding device 40b using the above formula.
[0066]
Σ shown in the above equation (2) is a back stress generated by contact between a cell 95 described later and the grinding operation surfaces 34a, 34b, and dh is a grinding surface of the cell 95 described later by the grinding operation surfaces 34a, 34b. The distance moved above, β (t) indicates the presence / absence of contact between the grinding surfaces 34a, 34b and the cell 95, and α, n indicate parameters indicating the grinding ability of the grindstone. The parameters α and n indicating the grinding ability of the grindstone are determined based on actual machining for both the master side grinding device 40a and the slave side grinding device 40b. Further, β (t) = 1 when the grinding operation surfaces 34a, 34b and the cell 95 are in contact, and β (t) = 0 when they are not in contact. Note that σ includes an external force f.
[0067]
The grinding amount du is calculated based on the parameters α, n, β (t) = 1, the distance dh that the grinding operation surfaces 34a and 34b have moved on the grinding surface of the cell 95 described later, and the back stress σ. It can be obtained by processing.
[0068]
Next, the machining simulation process will be described with reference to FIG.
[0069]
When the process shown in FIG. 5 is started, the grinding condition 50 described above is first input to the computer 10 through the process of ST70. This input process is performed by an operator of the computer 10. Subsequently, in ST71, based on the grinding condition 50, parameters α, n indicating the grinding ability of the grindstone are obtained by arithmetic processing. In the present embodiment, the grinding amount of the workpiece 42 necessary for performing the machining simulation of the shape of the grinding surface of the workpiece 42 is obtained using the parameters α and n. If the parameters α, n are acquired at least once after the exchange of the grindstones 35a, 35b, a machining simulation of the state of the grinding surface of the workpiece 42 can be performed.
[0070]
Here, how to obtain the parameters α, n will be described. The parameter α is obtained from the slope of the curve indicating the change in the grinding resistance within the spark-out time by grinding the workpiece 42 and acquiring the actual machining data of the time change in the grinding resistance. The parameter n is obtained by acquiring data on the relationship between the cutting speed of the grindstones 35a and 35b and the grinding resistance and creating a fitting curve.
[0071]
Next, with reference to FIG. 6, the acquisition method of the parameter (alpha) which shows the grinding capability of a grindstone is demonstrated. Regarding the processing shown in FIG. 6, actual machining data is acquired in advance before the machining simulation is performed, and actual machining data is not acquired every time the machining simulation is executed. FIG. 6 is a flowchart showing a method of acquiring actual machining data of the time change of the back stress.
[0072]
When the process shown in the figure is started, first, in the process of ST84, a grinding condition 50 for actually machining the workpiece 42 is input to the computer on the double-head grinding apparatus 20 side. In subsequent ST85, a plurality of workpieces 42 (three in this embodiment for one grindstone) are ground.
[0073]
In ST86, actual machining data of the time change of the back stress is acquired. In ST87, the actual machining data of the time change of the back stress is input to the first database 65 of the computer 10, and all the processes are completed. The acquisition of the actual machining data of the time change of the back stress described with reference to FIG. 6 is performed for each of the master side grinding device 30a and the slave side grinding device 30b of the double-head grinding device 20.
[0074]
FIG. 7 is a diagram showing the transition of the time change of the back stress. A to C in the figure show actual machining data of the temporal change of the back stress of the three workpieces 42 that have been ground, and D is the result of calculation using the obtained α.
[0075]
A range E shown in the figure indicates a time for grinding with the grindstones 35a and 35b moved toward the workpiece 42 at a constant cutting speed and the grindstones 35a and 35b and the workpiece 42 rotated. Range F represents the spark-out time. The spark-out time is a time for grinding by stopping the movement of the grindstones 35a and 35b while the grindstones 35a and 35b and the workpiece 42 are rotated. The parameter α is obtained by fitting D in the range F in the figure to A, B, and C.
[0076]
Next, a method for obtaining the parameter n indicating the grinding ability of the grindstone will be described using the flowchart shown in FIG. In the processing shown in FIG. 8, actual machining data is acquired in advance before the machining simulation is performed, and actual machining data is not acquired every time the machining simulation is executed. FIG. 8 is a flowchart showing a method of acquiring actual machining data regarding the relationship between the cutting speed of the grindstone and the back stress.
[0077]
When the process shown in the figure is started, first, in the process of ST88, a grinding condition 50 for actually machining the workpiece 42 is input to the computer 13 on the double-head grinding apparatus 20 side. In subsequent ST89, a plurality of workpieces 42 (three times for one grindstone in this embodiment) are ground under the condition that the cutting speed of the grindstones 35a and 35b is changed.
[0078]
In ST90, actual machining data of back stress with respect to the cutting speed of each of the grindstones 35a and 35b is acquired. In ST91, the actual machining data of the back stress for the cutting speed of the grindstones 35a and 35b is input to the first database 65 of the computer 10, and all the processes are completed.
[0079]
The actual machining data regarding the relationship between the cutting speed of the grindstone and the back stress described with reference to FIG. 8 is acquired for each of the master-side grindstone 35a and the slave-side grindstone 35b of the double-head grinding apparatus 20.
[0080]
FIG. 9 is a diagram showing the relationship between the cutting speed of the grindstone and the back stress. G shown in the figure is actual machining data showing the relationship between the cutting speed of the grindstone of the ground workpiece 42 and the back stress. H shown in the figure is a fitting curve created based on the actual machining data of G, and the parameter n is obtained from the slope of H.
[0081]
As described above, since the arithmetic processing is performed based on the parameters α and n obtained from the actual machining data, the difference between the shape of the ground surface of the workpiece 42 obtained by the arithmetic processing and the shape of the ground surface of the ground workpiece is calculated. And the simulation can be performed with high accuracy.
[0082]
As described above, the parameters α, n are obtained by the method described with reference to FIGS. 6 to 9, and step 71 shown in FIG. 6 ends, and the process proceeds to next ST 72.
[0083]
In ST72, cell division of the ground surface of the workpiece 42 is performed.
[0084]
Here, with reference to FIG. 10, the cell division | segmentation of the grinding process surface of the workpiece | work 42 is demonstrated. FIG. 10 is a diagram showing a grinding surface of a work divided into cells.
[0085]
As shown in the figure, the work 42 is divided into cells 95 whose width in the X direction is I and whose width in the Y direction is J. The numbers in parentheses shown in the figure are the addresses of the respective cells 95. For example, (1, 2) indicates that the address in the X direction is 1 and the address in the Y direction is 2. Note that the sizes of I and J can be appropriately determined according to the purpose and purpose of the simulation.
[0086]
When the cell division of the ground surface of the workpiece 42 is completed, the process proceeds from ST72 to ST73.
[0087]
In ST73, it is determined whether or not the cell 95 and the grinding operation surfaces 34a and 34b are in contact with each other by machining simulation. The cell that is determined to be in contact with the grinding operation surface 34a is the cell 95 that is determined to have been ground by machining simulation.
[0088]
Here, only the grinding operation surface 34a on the master side will be disclosed, and the contact determination between the grinding operation surface 34a on the master side and the cell 95 will be described. FIG. 11 is a diagram illustrating a state where the master side grinding operation surface is in contact with the cell-divided workpiece.
[0089]
The contact determination is performed based on the coordinate data of each cell 95 and the coordinate data of the grinding operation surface 34a. If the coordinate data of each cell 95 and the coordinate data of the grinding operation surface 34a match, the cell 95 is determined. And the grinding operation surface 34a are determined to be in contact with each other. K shown in the figure is a cell 95 determined not to be in contact with the grinding operation surface 34a, and L is a cell 95 determined to be in contact with the grinding operation surface 34a.
[0090]
Further, β (t) indicating the result of the contact determination described above is β (t) = 1 when it is determined that contact has occurred, and β (t) = 0 when it is not contacted. In ST73, if it is determined that contact has been made, the process proceeds to ST74, and if it is determined that contact has not been made, the process returns to ST73. In ST74, calculation processing of the back stress generated by the contact between the cell 95 and the grinding operation surface 34a is performed.
[0091]
Here, with reference to FIG. 12 thru | or 13, the calculation method of the back part stress which generate | occur | produces when the cell 95 and the grinding operation surface 34a contact is demonstrated. FIG. 12 is a diagram showing a contact portion between the cell and the grinding operation surface in the grinding state, and FIG. 13 is a diagram modeling the grinding state.
[0092]
As shown in FIG. 12, abrasive grains 96 are integrally disposed on the grinding operation surface 34 a by a binder 97. The arrows shown in the figure indicate the moving direction of the abrasive grains 96. A back portion stress is generated at the contact portion 98 between the cell 95 and the abrasive grains 96, and the abrasive grains 96 move in the direction of the arrow while being pressed by the back portion stress, whereby the cell 95 is ground.
[0093]
As shown in FIG. 13, in this example, the binder 97 shown in FIG. 12 was replaced with a spring 99 to model the grinding state. The back stress of the cell 95 can be obtained from the amount of contraction of the spring 99. The amount of contraction of the spring 99 is obtained by performing arithmetic processing based on the grinding condition 50.
[0094]
In ST74, when the back stress of the cell 95 is obtained by arithmetic processing, the process proceeds to ST75 and ST77. In ST75, the back stress obtained in ST74 is stored in the first database 65 of the computer 10, and the process proceeds to ST76. In ST76, the CPU 60 of the computer 10 performs a calculation process based on the actual machining data of the back stress stored in the first database 65, and the time variation of the back stress as shown in FIG. Data is output.
[0095]
In ST77, the grinding amount of the cell 95 is obtained by the above-described equation (2) for obtaining the grinding amount, and the arithmetic processing is performed based on the grinding amount of the cell 95. Shape and thickness distribution are required
The grinding amount du is the parameters α, n obtained in ST71 in the above equation, β (t) = 1 obtained in ST73, the distance dh that the grinding operation surface 34a has moved the grinding surface of the cell 95, and ST74 Calculated back stress σ_MIt is calculated | required by performing a calculation process based on these. Note that the calculation process for obtaining the grinding amount du is performed for all the cells 95 that are determined to be in contact in ST73. The shape and thickness distribution of the ground surface of the cell 95 are obtained by performing arithmetic processing based on the grinding amount du of the cell 95 thus obtained.
[0096]
As described above, in this embodiment, the grinding surface of the workpiece 42 is divided into a plurality of cells 95, and only the cells 95 determined to be ground are subjected to arithmetic processing of the state of the grinding surface. There is no need to perform arithmetic processing on the cell, and the time required for the arithmetic processing can be shortened. Further, it is possible to determine whether or not the workpiece 42 is normally ground by outputting and displaying the back stress, and damage to the workpiece 42 and the double-head grinding device 20 can be prevented.
[0097]
When the calculation processing of the shape and thickness distribution of the ground surface of the cell 95 is completed in ST77, the process proceeds to ST78 and ST80. In ST78, data related to the shape and thickness distribution of the ground surface of the cell 95 obtained in ST77 is stored in the second database 66 of the computer 10, and the process proceeds to ST79.
[0098]
In ST79, the CPU 60 of the computer 10 performs arithmetic processing based on the data stored in the second database 66, and the three-dimensional bird's eye view as shown in FIG. . FIG. 14 is a view showing a three-dimensional bird's-eye view of the ground surface of the workpiece.
[0099]
Thus, by outputting a three-dimensional bird's-eye view, the shape of the ground surface of the workpiece 42 can be easily recognized. Further, by performing processing simulation while repeatedly changing the grinding conditions, it is possible to know which parameter of the grinding conditions should be changed, and it is possible to easily optimize the grinding conditions. Further, by outputting a three-dimensional bird's-eye view during grinding, the state of the grinding surface of the workpiece 42 can be directly and three-dimensionally understood.
[0100]
In ST80, it is determined whether or not the arithmetic processing for all the cells 95 that have come into contact with the grinding operation surface 34a has been completed. If the determination is No, the process returns to ST73. If the determination is Yes, the process proceeds to ST81. In ST81, the grinding time is advanced by Δt. Thereby, the coordinate of the grinding position of the grindstone 34a is changed.
[0101]
In subsequent ST82, it is determined whether or not the grinding processing time input in ST70 has elapsed. If the determination is No, the process returns to ST73. If the determination is Yes, the process proceeds to ST83. In ST83, the output of the shape and thickness distribution of the grinding surface of the workpiece 42 for which the grinding processing has been completed is displayed, and the processing simulation processing for the state of the grinding surface of the workpiece 42 is completed.
[0102]
By applying the machining simulation method of the double-head grinding apparatus 20 as described above, the calculation is performed based on two data of the time change of the grinding resistance obtained by grinding the workpiece 42 and the relationship between the cutting speed and the grinding resistance. Thus, the state of the ground surface can be obtained by machining simulation. Therefore, the operator can know the state of the ground surface of the workpiece 42 after grinding by simply inputting the desired grinding conditions into the double-head grinding device 20 and starting the machining simulation process without grinding the workpiece. it can. Therefore, the grinding conditions can be optimized in a short time without depending on the skill level of the operator.
[0103]
Further, the grinding surface of the workpiece 42 is divided into a plurality of cells 95, and only the cells 95 that are determined to be in contact with the grinding operation surfaces 34a and 34b are subjected to arithmetic processing of the state of the grinding surface. There is no need to perform arithmetic processing on the cell 95, and the time required for the arithmetic processing can be shortened. Furthermore, it is possible to determine whether or not the workpiece 42 is normally ground by outputting and displaying the back stress, and damage to the workpiece 42 and the double-head grinding device 20 can be prevented.
[0104]
(Second embodiment)
In the second embodiment, the computer 10 shown in the first embodiment and the double-head grinding machine computer 13 are connected. Therefore, the same components as those in the first embodiment are denoted by the same reference numerals, and only differences from the machining simulation processing of the double-head grinding apparatus shown in the first embodiment will be described.
[0105]
FIG. 15 is a system configuration diagram of the machining simulation system of the second embodiment. In the present embodiment, similarly to the first embodiment, a machining simulation is performed based on actual machining data obtained from the double-head grinding apparatus 20. As shown in the figure, the computer 10 is connected to a double-head grinding machine computer 13 provided on the double-head grinding machine 20 online, and is configured to receive data from the double-head grinding machine computer 13. Yes.
[0106]
Next, with reference to FIG. 16, the process for acquiring the actual machining data of the time variation of the grinding resistance performed by the double-head grinding machine computer 13 will be described. FIG. 16 is a diagram showing a flowchart of processing for acquiring actual machining data of the time variation of the grinding resistance.
[0107]
When the process shown in FIG. 16 is started, in ST101, actual machining data of the time change of the back stress is acquired for each grinding process of the workpiece 42. In the subsequent ST102, the actual machining data of the temporal change of the back stress obtained in ST101 is stored in the double-head grinding machine computer 13, and the process proceeds to ST103. In ST103, it is determined whether or not the actual machining data of the time change of the back stress has been stored m times. If it is determined that the actual machining data has not been stored m times, the process returns to ST101.
[0108]
If it is determined that the actual machining data has been stored m times, the process proceeds to ST104. Note that m, which is the number of times the actual machining data is stored, can be appropriately determined according to the purpose of the workpiece 42 to be ground. In ST104, the time change data of the back stress is transferred to the computer 10 for processing simulation, and all the processes shown in FIG. 16 are completed.
[0109]
As described above, by acquiring the actual machining data of the time variation of the back stress of the ground workpiece 42, a lot of actual machining data including the device state of the double-head grinding device 20 that changes with time is accumulated. be able to.
[0110]
Next, with reference to FIG. 17, the processing in the computer 10 after the actual machining data of the time change of the grinding resistance acquired in FIG. 15 is transferred to the computer 10 will be described. FIG. 17 is a flowchart showing processing of the computer 10 after actual machining data is transferred to the computer 10.
[0111]
The computer 10 for simulation always determines whether or not there is transfer of actual machining data of back stress and time change from the computer 13 for the double-head grinding device 20 to the computer 10. Then, when it is determined that the actual machining data has been transferred from the computer 13 for the double-head grinding apparatus 20, that is, it is determined as Yes, the process proceeds to Step 106.
[0112]
In step 106, the actual machining data of the temporal change of the back stress stored in the first database 65 is updated. Note that the arithmetic processing for obtaining the parameter α is performed by a method similar to the method described in the first embodiment.
[0113]
In this way, by updating the actual machining data of the back stress and time change, the parameter α including the device state of the double-head grinding device 20 that changes with time is obtained, and the grinding surface of the workpiece with higher accuracy is obtained. It is possible to perform a machining simulation of the state.
[0114]
The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to such specific embodiments, and various modifications can be made within the scope of the gist of the present invention described in the claims. Deformation / change is possible.
[0115]
【The invention's effect】
  According to one aspect of the present invention, based on the change in grinding resistance with time and the relationship between the cutting speed and the grinding resistance.By the following formulaDesiredWorkGrinding amountduBased onThe
  du = ασ ⁿ dh (where σ is a grinding resistance generated by contact between the workpiece and the grindstone, α, n are parameters indicating the grinding ability of the grindstone, and dh is a distance that the grindstone has moved on the grinding surface of the workpiece. To do.)
  WaBy providing calculation means for calculating the state of the ground surface of the workpiece, it is possible to easily obtain the state of the ground surface of the workpiece without grinding the workpiece. Therefore, the workpiece evaluation and the grinding conditions can be optimized in a short time without depending on the skill level of the operator.
[0116]
  Also,Time change of grinding resistanceTheBased on actual machining data obtained by grinding the workpieceYou may ask. ThisThe time change of grinding resistance obtained from actual machining data is used to calculate the state of the ground surface of the workpiece.BecauseIt is possible to improve the accuracy of the state of the ground surface of the workpiece obtained by calculation.
[0117]
  Also, the relationship between the cutting speed and grinding resistance is based on actual machining data obtained by grinding the workpiece.You may ask for it. ThisThe calculation of the state of the ground surface of the workpiece uses the relationship between the cutting speed obtained from the actual machining data and the grinding resistance.BecauseIt is possible to improve the accuracy of the state of the ground surface of the workpiece obtained by calculation.
[0118]
  Moreover, you may provide the communication means which receives the data regarding the time change of the grinding resistance produced | generated with a grinding device. ThisSince the communication means can receive the data regarding the time change of the grinding resistance transmitted from the grinding apparatus, the data regarding the time change of the grinding resistance can be updated. As a result, the state of the grinding device that changes with time is reflected in the data relating to the time change of the grinding resistance, and the accuracy of the state of the ground surface of the workpiece obtained by calculation can be improved.
[0121]
  According to another aspect of the present invention, obtaining a first data that is a change in grinding resistance with time,
  Obtaining second data that is a relationship between the cutting speed and the grinding resistance;
  Based on the first data and the second dataFrom the following formulaDesiredWorkGrinding amountduBased onSaidProcess for obtaining the state of the ground surface of the workpiece by calculationWhen,
  du = ασ ⁿ dh (where σ is a grinding resistance generated by contact between the workpiece and the grindstone, α, n are parameters indicating the grinding ability of the grindstone, and dh is a distance that the grindstone has moved on the grinding surface of the workpiece. To do.)
  TheBy including the workpiece, the state of the ground surface of the workpiece can be easily obtained without grinding the workpiece. Therefore, the workpiece evaluation and the grinding conditions can be optimized in a short time without depending on the skill level of the operator.
[0122]
Also,The first data is obtained based on actual machining data obtained by grinding the workpiece.May be. As a result,The first data obtained from the actual machining data is used in the calculation of the state of the grinding surface of the workpiece. As a result, it is possible to improve the accuracy of the state of the ground surface of the workpiece obtained by calculation.
[0123]
  Also,The second data is obtained based on actual machining data obtained by grinding the workpiece.May be. As a result,The second data obtained from the actual machining data is used for the calculation of the state of the grinding surface of the workpiece. As a result, it is possible to improve the accuracy of the state of the ground surface of the workpiece obtained by calculation.
[0125]
  According to another aspect of the invention, a computer includes:
  1st data which is time change of grinding resistance,
  Based on the second data, which is the relationship between cutting speed and grinding resistanceFrom the following formulaDesiredWorkGrinding amountduBased onThe
  du = ασ ⁿ dh (where σ is a grinding resistance generated by contact between the workpiece and the grindstone, α, n are parameters indicating the grinding ability of the grindstone, and dh is a distance that the grindstone has moved on the grinding surface of the workpiece. To do.)
The workBy calculating the state of the ground surface of the workpiece, the state of the ground surface of the workpiece can be easily obtained without grinding the workpiece.
[Brief description of the drawings]
FIG. 1 is a system configuration diagram of a machining simulation system according to a first embodiment of the present invention.
FIG. 2 is a view showing a general double-head grinding apparatus.
FIG. 3 is a diagram showing grinding conditions used for processing simulation of a double-head grinding apparatus.
4 is a diagram showing an internal configuration of the computer shown in FIG. 1;
FIG. 5 is a flowchart showing a machining simulation process for obtaining the shape of a ground surface of a workpiece.
FIG. 6 is a flowchart showing a method of acquiring actual machining data of a time change of back stress.
FIG. 7 is a diagram showing the transition of the change over time in the back stress.
FIG. 8 is a flowchart showing a method for acquiring data on the relationship between the cutting speed of the grindstone and the back stress.
FIG. 9 is a diagram showing the relationship between the cutting speed of the grindstone and the back stress.
FIG. 10 is a diagram showing a grinding surface of a work divided into cells.
FIG. 11 is a diagram showing a state in which a grinding operation surface on the master side is in contact with a work divided into cells.
FIG. 12 is a diagram showing a contact portion between a cell and a grinding operation surface in a grinding state.
FIG. 13 is a diagram modeling a grinding state.
FIG. 14 is a view showing a three-dimensional bird's-eye view of a ground surface of a workpiece.
FIG. 15 is a system configuration diagram of a machining simulation system according to a second embodiment.
FIG. 16 is a view showing a flowchart of processing for acquiring actual machining data of time variation of grinding resistance.
FIG. 17 is a flowchart showing processing of the computer 10 after actual machining data is transferred to the computer 10;
[Explanation of symbols]
10 Computer
13 Computer for double-head grinding machine
20 Double-head grinding machine
30 Drive source
31 Work holder frame
32 Static pressure pad
33A, 33B, 33C V grooved roller
34a, 34b Grinding operation surface
35a, 35b
36a, 36b Grinding spindle
37a, 37b moving device
38a, 38b Driving device
40a, 40b Grinding equipment
41 Work holding device
42 Workpiece
48, 49, 52, 53 Center line
55 diameter
60 CPU
61 Input device
62 ROM
63 RAM
64 CLK
65 First database
66 Second database
67 Output device
95 cells
96 abrasive
97 binder
98 Contact part
99 spring

Claims (8)

Temporal change of the grinding resistance, cut on the basis of the relationship between the speed and the grinding force, based on the grinding amount du for the workpiece obtained by the following equation, to have a calculation means for calculating a state of grinding surfaces of the workpiece A processing simulation system for a grinding machine.
du = ασ ⁿ dh
However, (sigma) is the grinding resistance which generate | occur | produces when the said workpiece | work and a grindstone contact, (alpha) and n are the parameters which show the grinding capability of the said grindstone, and dh is the distance which the said grindstone moved on the grinding surface of the said workpiece | work.   2. The machining simulation system for a grinding apparatus according to claim 1, wherein the time change of the grinding resistance is obtained based on actual machining data obtained by grinding the workpiece.   2. The machining simulation system for a grinding apparatus according to claim 1, wherein the relationship between the cutting speed and the grinding resistance is obtained based on actual machining data obtained by grinding the workpiece. It is a processing simulation system of the grinding device according to claim 1,
A processing simulation system for a grinding apparatus, comprising: communication means for receiving data related to a temporal change in the grinding resistance generated by the grinding apparatus. Obtaining first data which is a time change of grinding resistance;
Obtaining second data that is a relationship between the cutting speed and the grinding resistance;
Based on the first data and the second data, based on the grinding amount du for the workpiece to be obtained by the following equation, and; and a step of obtaining by calculation the state of grinding surfaces of the workpiece Machining simulation method for grinding machine.
du = ασ ⁿ dh
However, (sigma) is the grinding resistance which generate | occur | produces when the said workpiece | work and a grindstone contact, (alpha) and n are the parameters which show the grinding capability of the said grindstone, and dh is the distance which the said grindstone moved on the grinding surface of the said workpiece | work.   6. The machining simulation method for a grinding apparatus according to claim 5, wherein the first data is obtained based on actual machining data obtained by grinding the workpiece.   6. The machining simulation method for a grinding apparatus according to claim 5, wherein the second data is obtained based on actual machining data obtained by grinding the workpiece. On the computer,
1st data which is time change of grinding resistance,
Is the relationship notch speed and the grinding force based on the second data, the machining simulation of the grinding apparatus for based on the grinding amount du for the workpiece to be obtained by the following equation, thereby computing the state of grinding surfaces of the workpiece program.
du = ασ ⁿ dh
However, (sigma) is the grinding resistance which generate | occur | produces when the said workpiece | work and a grindstone contact, (alpha) and n are the parameters which show the grinding capability of the said grindstone, and dh is the distance which the said grindstone moved on the grinding surface of the said workpiece | work.

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