JPH06335859A - Grinding device - Google Patents

Abstract

PURPOSE:To detect only the thermal displacement between a workpiece and a wheel spindle stock, excluding the influence of the deflection of the workpiece, etc. CONSTITUTION:A control means 160 grinds the outside diameter of the ground surface Wa of a workpiece W by a grinding wheel 19 by shifting a wheel spindle stock 13 through a driving means 100, and in the intermediate course, the wheel spindle stock 13 is once retreated and then advanced again. A judging means 130 judges the time point when the outside diameter of the ground surface Wa of the is reduced through the grinding by the advance of the wheel spindle stock 13, from the detection value of the outside diameter on the worked surface Wa of the workpiece W by a measuring means 120. At this time point, a measuring means 140 calculates the thermal displacement quantity between the workpiece W and the wheel spindle stock 13 on the basis of the position of the wheel spindle stock 13 detected by a position detecting means 110 and the outside diameter of the ground surface Wa measured by the measuring means 120, and a correcting means 150 corrects the position of the wheel spindle stock 13 detected by the position detecting means 110, on the basis of the thermal displacement quantity calculated in the above and transmits the value to a control means 160.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grinding device for grinding a cylindrical outer diameter of a workpiece, and more particularly to a grinding device having a function of correcting an error in a detected position of a wheel head due to a thermal displacement due to a temperature change of each part. Seed grinding device.

[0002]

2. Description of the Related Art In a grinding machine such as a cylindrical grinder, as shown in FIG. 21, centers 15a, 1 of headstock and tailstock are used.
Grinding wheel 19 that rotates with respect to the workpiece W supported by 6a
The outer diameter of the surface to be ground is ground by sending in a grindstone stand having. As shown by the line G in the diagram of FIG. 20, the grinding wheel is moved to the rough grinding feed G1, the fine grinding feed G2, and the fine grinding feed G3 while sequentially decreasing the feed speed, thereby grinding the workpiece W. The outer diameter of the surface (for example, Wa) is reduced as shown by a line H if it is represented by a value converted into the position of the grinding wheel head.
The lines G and H are the thermal displacement between the workpiece W and the grindstone base due to the bending of the workpiece W and its support portion due to the grinding resistance and the temperature change (specifically, the surface to be ground of the workpiece W and the grindstone). Car 1
9 thermal displacements between contact points relative to the other party) usually do not match.

Therefore, in a conventional grinding apparatus using a measuring device such as an in-process gauge for continuously measuring the outer diameter of the surface to be ground during processing, the outer diameter of the surface Wa to be measured is measured by the measuring device. Based on the position of the grinding wheel head detected by a position detector such as an encoder, the difference d (see FIG. 20) between the line G and the line H at the time when the final machining cut is completed is calculated,
Thereby, the position of the grinding wheel head detected by the position detecting means is corrected to correct an error in the detected position of the grinding wheel head 13 due to thermal displacement. Then, in the subsequent grinding of the surfaces Wb, Wc (see FIG. 21) and the like, indirect sizing is performed using the corrected detection value of the position detector to eliminate the processing error due to thermal displacement and the processing time. Has been shortened.

[0004]

However, the above-mentioned difference d is affected not only by the thermal displacement due to the temperature change but also by the bending of the workpiece W or the like due to the grinding resistance, and especially when the grinding resistance is large at the time of fine grinding. The latter deflection is large, and thus the above-mentioned conventional technique cannot completely correct the error in the detected position of the grinding wheel head due to the thermal displacement, which causes a machining error.

An object of the present invention is to solve such a problem by eliminating the influence of bending of the work W or the like and detecting only the thermal displacement between the work and the grindstone.

[0006]

To this end, the grinding apparatus according to the present invention, as shown in FIG. 1, has a grinding wheel base 13 having a grinding wheel 19 which is rotationally driven by a motor, the grinding wheel 19 and the grinding wheel 19 thereby. Driving means 100 for relatively moving the grindstone base 13 and the workpiece W in a direction in which the workpieces W to be ground come close to and away from each other, and the grindstone base 1 for the workpiece W.
Position detecting means 110 for detecting the position of No. 3 and measuring means 120 for measuring the outer diameter of the surface Wa to be ground of the workpiece W during grinding.
Then, the driving means 100 is operated to grind the outer diameter of the surface Wa to be ground of the workpiece W by the grinding wheel 19, and the grindstone base 13 is once retracted with respect to the workpiece W during the grinding. After the grinding wheel 19 is disengaged from the work W, the grinding wheel 19 is moved forward again to grind the work W again by the grinding wheel 19 and the work W by the measuring means 120.
Determination means 130 for determining the time point at which the grinding wheel is brought into contact with the workpiece due to the forward movement of the grinding wheel base 13 after the retreat, based on the detected value of the outer diameter of the grinding surface Wa of A workpiece based on the position of the grindstone 13 detected by the position detecting means 110 at the time when it is determined that an object has contacted and the outer diameter of the ground surface Wa of the workpiece W measured by the measuring means 120. Arithmetic means 140 for calculating the amount of thermal displacement of the whetstone base 13 with respect to W
And the grindstone base 1 detected by the position detecting means 110.
And the correction means 150 for correcting the position of No. 3 on the basis of the thermal displacement amount calculated by the calculation means 140.

[0007]

The control means 160 controls the position of the grindstone base 13 through the driving means 100 to grind the outer diameter of the surface Wa to be ground of the workpiece W by the grinding wheel 19. During this grinding, the control means 160 once retracts the wheel head 13 and causes the wheel wheel 19 to move.
The workpiece W and then move it forward again to move the workpiece W
To grind. By the forward movement after the backward movement, the grinding wheel 19 again contacts the surface to be ground Wa and starts grinding the outer diameter thereof, and the judging means 130 judges the grinding start time. At the time of starting the grinding, since the grinding resistance is small, the deflection of the work W or the like is substantially 0. At this time, the calculating means 140 measures the position and the position of the grindstone 13 detected by the position detecting means 110. Based on the outer diameter of the ground surface Wa of the workpiece W measured by the means 120, the amount of thermal displacement between the workpiece W and the grindstone 13 due to the temperature change of each part is calculated.
The correction means 150 corrects the position of the grinding wheel base 13 detected by the position detection means 110 and transmitted to the control means 160 based on the calculated thermal displacement amount, and thereby the grinding wheel base 13 detected by the position detection means 110. The error due to the thermal displacement of the position is compensated.

[0008]

As described above, according to the present invention, the error due to the thermal displacement of the position of the grinding wheel head detected by the position detecting means is compensated, and the deflection of the workpiece etc. at the time of the compensation is substantially zero. Therefore, the error in the detection value of the position detecting means due to the bending of the workpiece in this type of grinding device is excluded, and the processing error due to the error in such a detected value in the subsequent direct sizing or indirect sizing Can be excluded.

[0009]

EXAMPLE A first example will be described below with reference to FIGS. As shown in FIG. 2, a headstock 14 and a tailstock 16 for bearing a main spindle 15 and a tailstock 16 are placed on the left and right sides of a worktable 12, which is guided and supported on a bed 11 of a grinding machine 10 so as to be movable in the left-right direction (Z direction). The workpieces W are coaxially provided so as to face each other in the direction, and the work W has centers 15a, 1 provided on the spindle 15 and the tailstock 16.
Both ends are supported by 6a. Spindle 15 is headstock 1
The work W is rotated by a motor 18 provided on the No. 4, and the left end of the work W is engaged with a detent member 17 projecting from the main shaft 15 and rotated together with the main shaft 15.

A grindstone base 13 is guided and supported on the bed 11 so as to be movable in a horizontal X direction orthogonal to the Z direction, and a grindstone 19 such as a CBN grindstone is parallel to the spindle 15 on the grindstone base 13. It is supported by a simple grindstone shaft 20 and is rotationally driven by a motor 22 via a V-belt rotation transmission mechanism 21. The servomotor 23 provided in the bed 11 is controlled and driven by a drive device 41 that operates based on a control pulse distributed from a pulse distribution circuit 34 of the numerical control device 30, and the grindstone base 13 is driven via a feed screw device (not shown). To feed in the X direction. Position detector 2 such as encoder
Reference numeral 5 detects the moving position of the grindstone 13 via the rotation angle of the servomotor 23, and the detected value is the sensor controller 4
It is input to the numerical control device 30 via 2.

The in-process measuring device 24 installed on the work table 12 has a surface W to be ground of the work W being ground.
The outer diameter dimension of a is continuously measured directly, and the measurement signal (analog signal) is input to the numerical controller 30.

As shown in FIG. 2, the numerical control device 30 has a
Central processing unit (CPU) that controls and manages the entire grinding machine
3, a memory 32, an interface 33 for exchanging data with the outside, and a pulse distribution circuit 34 for distributing and transmitting drive pulses in response to a command from the CPU 31. The measuring device 24 is connected to the CPU 31 via the AD converter 35, and the sensor controller 42 is connected to the CPU 31. This sensor controller 42 is a CPU
The position detector 25 is connected to the position detector 25 described above. Further, the interface 33 includes an emergency stop button 40a, a processing button 40b, an operation preparation button 40c,
Numerical value input button 40d for inputting control data, CRT
An input device 40 having a display device 40e and the like is connected, and the pulse distribution circuit 34 is connected to the servo motor 23 described above via a drive device 41.

In the memory 32, an in-process gauge machining program for in-process machining the workpiece W,
Each program such as a machining program for indirect sizing for indirectly sizing the workpiece W, a correction value calculation program for calculating a correction value for thermal displacement based on input data from the measuring device 24 and the position detector 25, Also, data such as the diameter R of the grinding wheel 19, the value of an internal switch described later, and the like are stored. The grinding wheel diameter R stored in the memory 32 is updated every time the grinding wheel 19 is shaped by the truing device 26.

In the relationship between the present embodiment and the claims, the servo motor 23 is the driving means 100, the position detector 25 is the position detecting means 110, the measuring device 24 is the measuring means 120, and
The CPU 31 and the memory 32 serve as the determination means 130 and the computing means 140, the CPU 31 and the sensor controller 42 serve as the correction means 150, and the CPU 31 and the pulse distribution circuit 34.
Respectively constitute the control means 160. The overall structure of the grinding machine 10 described above and the relationship with the claims are common to all the embodiments.

Next, the operation of the first embodiment constructed as described above will be described with reference to the flow charts shown in FIGS.
~ It demonstrates by the explanatory view shown in FIG. When the operation preparation button 40c of the input device 40 is pressed, the CPU 31 starts the operation of the main program shown in the flowchart of FIG. 3, sets the value of the internal switch in the memory 32 to 1 in step S1, and sets the value from the processing button 40b. Wait for input. If the workpiece W is set and the machining button 40b is pressed, C
The PU 31 advances the control operation from step S2 to step S3 to step S4, and performs the first grinding process described later. When the first grinding process is completed, the CPU 31
Sets the internal switch to 2 in step S5 and returns the control operation to that before step S2. When the next workpiece W is set and the machining button 40b is pressed, the CPU 31 controls the control operation from step S2 to step S3 to step S6.
Then, the second and subsequent processes, which will be described later, are performed. If the emergency stop button 40a is pressed during these processes, the CPU
In step 31, the process proceeds from step S7 to step S8 to set the internal switch to 0, and after step S3, the operation of the grinding device is stopped in step S9 to end the operation.

Note that the CPU 31 does not perform the machining after the previous machining is completed in step S2a as shown by the chain double-dashed line in FIG. 3 except when the operation preparation button 40c is pressed as described above. It is determined whether or not a predetermined time (for example, 2 to 3 hours) has elapsed. If the predetermined time has elapsed, the internal switch is set to 1 in step S2b, the process proceeds to step S3, and the predetermined time has not elapsed. In this case, step S2b is skipped and the process directly proceeds to step S3. In addition, the determination in step S2a is
When the sequence switch for rotating the grinding wheel 19 is off for a predetermined time, when the sequence switch for discharging the coolant is off for a predetermined time or longer, and when further continuous machining is performed, a predetermined number (or a predetermined number of times) or more of machining is performed. The internal switch may be set to "1" each time. In the last case, the temperature rise with the passage of machining time gradually converges and approaches a constant temperature, so the predetermined number (or the predetermined number of times) in this case is not constant, and gradually increases as the time from the start of machining passes. The number (or number of times) is increased to converge to a certain number (or number).

The first first stage grinding process of the first embodiment is a grinding process using an in-process gauge machining program, which will be described with reference to FIGS. 4 and 5. First, the grinding wheel 19 rotates, and the workpiece W supported by the headstock 14 and the tailstock 16 is rotated at a predetermined speed by the motor 18, and the numerical controller 30 fast-forwards and advances the grinding wheel 13 in step S10. Let That is, the CPU 31 decodes the grindstone rapid feed command in the machining program and gives the command value to the pulse distribution circuit 34, whereby the pulse signal sent from the pulse distribution circuit 34 is applied to the servo motor 23 via the drive device 41. As a result, the servomotor 23 is driven, and as shown by the line E0 in FIG.
Is fast forwarded to a predetermined coordinate position, and the grinding wheel 19 is at the position immediately before contacting the workpiece W.

Next, in steps S11 and S12, the CPU 31 sets the wheel head 13 as shown by the line E1 in FIG.
The workpiece W at the preset first roughing feed speed.
1st rough grinding. In this case, when the grindstone base 13 is cut and fed, the cutting feed position of the grindstone base 13 that changes moment by moment is detected by the position detector 25, and the detected value is input to the CPU 31 via the sensor controller 42. The tracing stylus 34a of the measuring device 24 moves to the workpiece W side during the first rough polishing and is engaged with the ground surface Wa of the workpiece W, thereby performing in-process measurement of the outer diameter of the ground surface Wa. The measured value is converted into a digital signal by the AD converter 35 and input to the CPU 31. If the first rough grinding progresses and the measuring device 24 generates a first sizing signal corresponding to the first rough grinding completion diameter (step S12), the first rough grinding is completed, and the grinding wheel head 13 is fast-forwarded by a predetermined amount and retracted. Then, (step S13), the grinding wheel 19 is separated from the surface Wa to be ground.

Next, the CPU 31 executes steps S14 and S.
At 15, the grindstone base 13 is again moved forward at a preset second rough grinding feed speed (the same as the first rough grinding feed speed in this embodiment), and the workpiece W is moved in the same manner as in the first rough grinding. Second rough grinding is performed. In the initial stage of this second rough grinding, in parallel with this, as shown in steps S16 and S17, the position detector 25
The cutting feed position of the grindstone base 13 detected by is corrected according to the thermal displacement between the workpiece W and the grindstone base 13 due to the temperature change of each part. This correction is for the grinding wheel 19
However, it is performed at the time when the second rough grinding feed again makes contact with the surface Wa to be ground to start grinding. The grinding wheel head position correction of this step S17 performed at the time of the first first grinding step is performed in order to perform the thermal displacement correction due to the temperature decrease due to the interruption of the grinding processing due to the change of the operator or the like. .

First, referring to FIG. 10, the diameter B of the grinding surface Wa measured by the measuring device 24 and the position detector 2 are measured.
The relationship of the output signal value S of 5 (value when there is no thermal displacement) will be described. When there is no thermal displacement, the grinding wheel 19 is the workpiece W.
There is a relationship between the diameter B of the surface to be ground Wa detected by the measuring device 24 and the output signal value S of the position detector 25 when the surface to be ground Wa is lightly contacted.

[0021]

## EQU1 ## S-R / 2 = B / 2 where R: grinding wheel 19 stored and updated in the memory 32
Position detector 2 in the same situation when there is thermal displacement
The output signal value S of 5 is shifted by the value F of thermal displacement between the workpiece W and the grindstone 13, whereby the value F of thermal displacement is obtained. As will be described later, the thermal displacement F is used to correct the output signal value (detection value) of the position detector 25 due to the thermal displacement between the workpiece W and the grindstone 13.

Returning to the continuation of the description of steps S16 and S17 in the flowchart of FIG. 4, the outer diameter of the surface to be ground Wa is determined by the grinding wheel 19 coming into contact with the surface to be ground Wa and starting grinding by the second rough grinding feed. If the measuring device 24 detects the decrease, the CPU 31 determines in step S17 the cutting feed position of the grinding wheel base 13 detected by the position detector 25.
Correction is made according to the thermal displacement between the workpiece W and the grinding wheel base 13.
The correction value used for this is calculated by the correction value calculation program shown in FIG. That is, the CPU 31 inputs the output signal value A (value affected by thermal displacement) of the position detector 25 and the output signal value B (diameter) from the measuring device 24 in steps S30 and S31. Then step S
In 32, the output signal value B is converted into the output signal value S of the position detector 25 (the value in the case where there is no thermal displacement) by the equation 1, and in step S33 the following equation

[0023]

## EQU2 ## The correction value F for the thermal displacement is calculated by F = S-A. After that, the output value of the position detector 25 (the cutting feed position of the grindstone base 13) is corrected by the sensor controller 42 by the correction value F, digitally converted by the AD converter 36, and transmitted to the CPU 31.

These steps S16 and S17 are carried out only once when the reduction of the outer diameter of the surface to be ground Wa is started during the second rough polishing feed. The second rough grinding progresses, and the measuring device 2
If 4 produces a second sizing signal corresponding to the second rough grinding completion diameter (step S15), the second rough grinding ends, and step S
Move to the fine grinding of 18 and S19.

The operation state in steps S11 to S15 will be described below with reference to FIG. In the figure, the solid line A indicates the cutting feed position of the grindstone 13 detected by the position detector 25, the alternate long and short dash line E indicates the actual position of the grindstone 13, and the solid line C indicates the ground surface Wa detected by the measuring device 24. The diameter is converted to the position of the grindstone base 13 by the formula 1. In the first rough grinding, the position of the wheel head 13 detected by the position detector 25 decreases as shown by the line A1, and the actual position of the wheel head 13 decreases as shown by the line E1. There is a difference due to. If grinding is performed by the grinding wheel 19, the diameter of the ground surface Wa is reduced, but the measurement of the ground surface Wa by the measuring device 24 is performed only after the point Ca. The above-mentioned first sizing signal is generated at the point Aa, and the grindstone 13 is moved to the line A2 (detection position) and the line E.
As shown in 2 (actual position), the predetermined amount of fast-forward is retracted.
As a result, the grinding wheel 19 is separated from the surface to be ground Wa and the diameter of the surface to be ground Wa does not change.

When the second rough grinding is started at the point Ab, the detected position and the actual position of the wheel head 13 start to decrease as shown by the lines A3 and E3. When the actual position E3 decreases and intersects with the line C3 of the surface to be ground Wa, the grinding wheel 19 contacts the surface to be ground Wa to start grinding, and the surface W to be ground as shown by the line C3.
The diameter of a begins to decrease. The measuring device 24 detects the time point Cb at which the decrease starts. At this point in time, as shown in step S17 of FIG.
The position of the grindstone base 13 in the cutting feed direction detected by is corrected according to the thermal displacement, and the subsequent position detected by the position detector 25 coincides with the actual position E3 of the grindstone base 13 as indicated by A3 ′. It will be what you did. The correction of the grinding wheel head position for removing the influence of the thermal displacement is performed by correcting the output signal value of the position detector 25 in the sensor controller 42 based on the calculated correction value.

Returning again to the continuation of the description of the in-process gauge machining program shown in FIG. 4, steps S14 and S1.
When the second rough grinding of No. 5 is completed, steps S18 and S1
9 Move to fine grinding. When the fine grinding (line E4 in FIG. 8) is performed and the measuring device 24 generates the third sizing signal corresponding to the fine grinding completed diameter, the fine grinding is completed, and steps S20 and S20 are performed.
21 to fine grinding. Then, if the fine grinding (line E5 in FIG. 8) is performed and the measuring device 24 generates the fourth sizing signal corresponding to the fine grinding completed diameter, the fine grinding is finished, and in step S22 the grindstone 13 reaches the original position. The rapid retreat (line E6 in FIG. 8) is performed, and the in-process gauge machining program shown in FIG. 4 is completed.

Next, other surfaces to be ground Wb, W of the same workpiece W
In order to grind c (see FIG. 21) by indirect sizing, the workpiece table 12 is moved to the left by a predetermined amount in advance, and the grinding wheel 19 is attached to the next stage where the indirect sizing of the workpiece W is performed. Let

In this state, the position of the grindstone 13 in the cutting feed direction detected by the position detector 25 is corrected in accordance with the thermal displacement, and the corrected grindstone 1 is corrected.
Using the cutting feed position of 3, the machining by the machining program for indirect sizing shown in FIG. 6 is performed on the second stage of the workpiece W. That is, first, in steps S40 and S41, the CPU 31 causes the target position information given in advance and the position detector 25 to detect and correct the above-described grinding wheel mount 1.
Calculating the wheel head rapid feed amount K based on the current position information of 3,
A command value is given to the pulse distribution circuit 34, the servo motor 23 is driven through the drive device 41, the grindstone base 13 is fast-forwarded and advanced by the calculated feed amount K (line E0 in FIG. 8), and the grindstone 19 is moved. The work W is moved until just before contacting it.

Next, in steps S42 and S43, the CPU 31 calculates the rough grinding feed amount L in the same manner as described above, drives the servomotor 23 to move the grinding wheel head 13 forward by this feed amount L, and works with the grinding wheel 19. The object W is roughly ground. Similarly, the CPU 31 advances the grindstone base 13 by the feed amount N in steps S44 and S45 to perform fine grinding, and advances the grindstone base 13 by the feed amount P in steps S46 and S47 to perform fine grinding. Next, the CPU 31 calculates the rapid feed amount Q in steps S48 and S49, fast-forwards and retracts the grindstone base 13 by this feed amount Q to return it to the original position, and completes the indirect sizing machining program shown in FIG. In addition, in this embodiment, the example in which the rough-polishing feed amount L, the fine-polishing feed amount N, and the fine-polishing feed amount P are calculated based on the rough-polishing completion position, the fine-polishing completion position, and the fine-polishing completion position has been described. Alternatively, the rough-working feed amount L, the fine-working feed amount N, and the fine-working feed amount P set in the machining program for indirect sizing may be given to the pulse distribution circuit 34. According to this indirect sizing, the grinding cycle time is shortened because the measurement by the measuring device 24 is unnecessary.

When the first machining is finished as described above, the workpiece W is replaced with the next one, and the second and subsequent machining shown in step S6 of the flowchart of FIG. 3 is performed. In the second and subsequent processes, the first-stage grinding process is performed using the in-process gauge machining program shown in the flowchart of FIG. 7 instead of that of FIG. The grinding process of the second step is performed by the indirect sizing process program shown in FIG. 6, as with the first process.

In the second and subsequent first step grinding processes shown in FIG. 7, steps S12 to S14, step S16 and step S17 from the first first step grinding process shown in FIG.
Is omitted. That is, the wheel head position is not corrected by fast-forwarding and retracting the wheel head 13 and performing the rough grinding feed again. Instead, in order to correct the thermal displacement due to the temperature rising as the workpiece W is continuously machined before finishing the fine grinding and retreating the grindstone 13 fast-forwarding, in step S21A, a correction value is calculated and the grindstone position is corrected. 1
This is done every time the book processing is completed. This correction value calculation is performed on the surface Wb to be ground measured by the measuring device 24 at the end of fine grinding.
Is performed by taking out the difference (see d in FIG. 20) between the outer diameter of the wheel and the position of the grinding wheel base 13 detected by the position detector 25, and the specific method is substantially the same as that shown in the flowchart of FIG. is there. The position detector 2 is used to correct the wheel head position.
This is performed by correcting the output value of 5 (cutting feed position of the grinding wheel base 13) by the difference in the sensor controller 42.

Next, the second embodiment will be described. In the second embodiment, the main program shown in the flowchart of FIG. 3 described in the first embodiment is executed in the same manner, and in step S4 of the main program, the in-process machining program of FIG. 4 described in the first embodiment. Is executed. However, in step S6 of the main program, grinding processing is performed according to the flowcharts shown in FIGS. 11 to 14 instead of the indirect sizing processing program shown in FIG. The second and subsequent grinding operations of the second embodiment are direct sizing operations using the measuring device 24, and the processing diameter of the workpiece W when switching between rough grinding, fine grinding, fine grinding, etc. The correction is made according to the properties of the grinding surface of the grinding wheel 19 (sharpness, roundness, surface roughness, protruding height of abrasive grains, etc.), which improves the machining accuracy of the workpiece. it can.

First, in step S101, the workpiece W and the grinding wheel 19 are rotated at a preset speed, and the grinding wheel base 13 is rotated.
At a preset feed speed, and fast-forwards and advances to a predetermined position immediately before the grinding wheel 19 contacts the workpiece W (see FIG. 8).
Line E0). After step S102, the calculation check correction program, which will be described later, is repeatedly executed for each revolution of the workpiece W. In step S103, the spindle 15 is rotated at the spindle rotation speed Sb, and at the feed speed Fb until the output of the position detector 25 reaches a value corresponding to the cutting completion diameter Pb (both are preset and stored in the memory 32). Thirteen
To advance the rough grinding of the workpiece W. Step S
In 104, it is judged whether or not the grinding condition, that is, the feed rate and the cutting completion diameter are corrected by the calculation check correction program.
If correction is being performed, the process proceeds to step S106, and the grinding wheel head 13 is moved to the cutting completion diameter Pa at the corrected feed speed Fa.
To move forward. If not corrected, step S10
5, the process proceeds to step S109 to determine whether the current machining diameter Da from the measuring device 24 and the cutting completion diameter Pb are the same. If they are the same, the process proceeds to step S109.
Return to 03.

On the other hand, when step S106 is completed and the process proceeds to step S107 following step S106, it is judged whether or not the feed rate and the cutting completion diameter are corrected by the calculation check correction program, and if so, step S106. Then, the grindstone 13 is advanced to the cutting completion diameter Pa at the further modified feed speed Fa. If it is not corrected, the process proceeds to step S108, and it is determined whether the current machining diameter Da from the measuring device 24 and the cutting completion diameter Pa are the same. If they are the same, the process proceeds to step S109.
If they are not the same, the process returns to step S106. Rough grinding (lines E1 and E3a in FIG. 8) is performed by the above steps S103 to S108.

In steps S109 to S114, fine grinding (line E4a in FIG. 8) is performed. In this fine grinding as well, except that the spindle rotation speed Sc, the feed speed Fc, and the cutting completion diameter Pc which are preset and stored in the memory 32 are different.
Similar to the above-described rough grinding, the calculation check correction program described later is executed for each rotation of the workpiece W, and the current machining diameter Da from the measuring device 24 is the original cutting completion diameter Pc or the corrected cutting completion diameter. If Pa, step S121
Proceed to.

In steps S115 to S120, fine grinding (line E5a in FIG. 8) is performed. Also in this fine grinding, except that the spindle rotation speed Sd, the feed speed Fd and the cutting completion diameter Pd which are set in advance and stored in the memory 32 are different.
Similar to the above-described rough grinding, the calculation check correction program described later is executed for each rotation of the workpiece W, and the current machining diameter Da from the measuring device 24 is the original cutting completion diameter Pd or the corrected cutting completion diameter. If Pa, step S121
Proceed to.

In step S121, correction value calculation and wheel head position correction are performed in order to correct the thermal displacement due to the temperature rising as the workpiece W is continuously processed. This correction value calculation is performed by taking out the difference (see d in FIG. 21) between the outer diameter of the surface to be ground measured by the measuring device 24 and the position of the wheel head 13 detected by the position detector 25 at the end of the fine grinding. That is, the wheel head position correction is performed by correcting the output value of the position detector 25 (the cutting feed position of the wheel head 13) by the sensor controller 42 by the difference.

In step S122, the grinding wheel base 13 is fast-forwarded and retracted to the original position (line E6a in FIG. 8), the rotation of the workpiece W and the grinding wheel 19 is stopped, and the grinding program is stopped. Here, the feed speed is set to have a relationship of Fb>Fc> Fd, the cutting completion diameter is set to have a relationship of Pb>Pc> Pd, and the spindle rotation speed is Sb>Sc> S.
It is set so as to have a relationship of d.

Next, referring to FIGS. 13 and 14, a calculation check correction program executed in step S102 of the grinding program of FIGS. 11 and 12 will be described. This calculation check correction program is repeatedly executed every one revolution of the work piece in parallel with the steps after step S103 of the grinding program. In step S130, it is determined whether the current machining diameter Da output from the measuring device 24 during one rotation is larger than the maximum diameter Db stored in the memory 32. If larger, the process proceeds to step S131 and is stored in the memory 32. The maximum diameter Db is updated to the current machining diameter Da and the process proceeds to step S132. If it is not larger, the process proceeds to step S132 without updating.

In step S132, it is determined whether or not the current machining diameter Da during one rotation output from the measuring device 24 is smaller than the maximum diameter Dc stored in the memory 32. If smaller, the process proceeds to step S133 and is stored in the memory 32. The maximum diameter Dc that has been set is updated to the current machining diameter Da, and step S1 is performed.
Proceed to 34. If it is not larger, the process proceeds to step S134 without updating. Until it is determined in step S134 that the workpiece W has made one revolution, steps S130 to S
Repeat 134.

When the workpiece W makes one revolution, step S
At 135, the pre-machining diameter Df before one rotation stored in the memory 32 is updated to the current machining diameter De after one rotation stored in the memory 32. The current machining diameter De after one rotation stored in the memory 32 in step S136 is the measuring device 24.
To the current machining diameter Da. In step S137, the workpiece machining diameter Dg stored in the memory 32 is selected based on the position of the wheel head 13, and in step S138 Dg <D.
Determine if a. If Dg <Da, step S
Proceed to 140, and if Dg <Da is not satisfied, step S13.
9, the A is set to 1, and the process proceeds to step S140.

In step S140, the deflection amount Ba of the workpiece diameter is calculated based on the maximum diameter Db and the minimum diameter Dc stored in the memory 32. In step S141, the allowable value Bb of the shake amount stored in the memory 32 is selected according to the current machining diameter Da, and in step S142, it is determined whether Bb <Ba. If Bb <Ba is not satisfied, step S144 is performed as it is.
If Bb <Ba, the process proceeds to step S143, A is set to 1, and the process proceeds to step S144. A plurality of the shake amounts Bb are set according to the current machining diameter, and are set to be smaller as the machining diameter becomes smaller.

In step S144, the pre-machining diameter Df before one rotation and the current machining diameter D after one rotation stored in the memory 32.
The reduction amount Ea of the workpiece diameter is calculated based on e. Step S
In 145, the allowable value Eb of the reduction amount stored in the memory 32 is selected according to the current machining diameter Da, and in step S146 it is determined whether Eb> Ea or Eb <Ea. When the current machining diameter Da falls within the range of Da1 to Da3 (machining diameter within the range of rough grinding), the judgment of Eb> Ea is selected, and the current machining diameter Da is Da3 to Da7 (for fine grinding and fine grinding). When it falls within the range of the processing diameter), the judgment of Eb <Ea is selected.
That is, when the amount of decrease in the workpiece diameter during the rough grinding is small, it is determined that the grinding surface of the grinding wheel is deteriorated, and when the amount of decrease is large during the fine and fine grinding, it is There is a lot of bending of the workpiece, and by slowing down the feed rate of the grindstone during precision and fine grinding, the workpiece springs back and the workpiece begins to sharply ablate, which determines that the machining accuracy of the workpiece deteriorates. There is. If YES in step S146, step S146
Proceeding to 147, A is set to 1 and proceeding to step S148. If NO, proceeding to step S152. The allowable value Eb of the reduction amount is set in plural according to the current machining diameter, and is set to be smaller as the machining diameter becomes smaller.

In step S148, it is determined whether A is 1, and if A is 1, the process proceeds to step S149, and if A is not 1, the process proceeds to step S152. In step S149, the remaining grinding amount T0 is calculated. The remaining grinding amount T0 is measured by the measuring device 24.
Is a value obtained by subtracting a machining diameter Dp (= S−R / 2) obtained from the position S of the grindstone 13 and the diameter R of the grinding wheel 19 from the machining diameter Da of the above. In step S150, the cutting completion diameter Pa is calculated based on the following calculation formula. For example, the completed diameter Pb
Is changed to Pa (> Pb), the allowable value of the reduction amount that can be tolerated when the processing diameter becomes Pb in the micro-laboratory is E
b, the current remaining grinding amount is T0, the current reduction amount is E0,
If the current cutting depth per revolution of the workpiece is U,

[0046]

From k = T0 / E0, E1 = (T0 + U) / (k + 1), the reduction amount E1 after one rotation can be predicted.

[0047]

## EQU4 ## T1 = kE1, E2 = (T1 + U) / (k + 1), ... Ti-1 = kEi-1, Ei = (Ti- Ei is calculated until the reduction amount Ei after i rotations can be predicted from 1 + U) / (k + 1), and becomes equal to or less than the allowable value Eb.

[0048]

[Equation 5] Pa = Pb + E1 + E2 ... + Ei In step S151, the feed rate F is calculated based on the following calculation formula.
Calculate a. For example, during step S146
When it is determined that b <Ea, T0 is the amount of grinding remaining at the time when it is determined that Eb <Ea, E0 is the reduction amount when it is determined that Eb <Ea, and Eb is the machining diameter (determined as Eb <Ea. Permissible reduction amount selected according to the machining diameter at the time of machining, U is the current cutting depth per revolution of the workpiece, and Ua is E
If it is determined that b <Ea, Eb = Ea, the cutting amount per one revolution of the workpiece, and Tp is the remaining amount of grinding at the start of polishing,

[0049]

## EQU6 ## k = T0 / E0, Ua = (Tp- (T0-kEb)). Times.U / Tp Fa = Ua.times.current spindle rotational speed A is set to 0 in step S152.

In step S153, the maximum diameter Db is set to the finish diameter, and in step S154, the minimum diameter Dc is set to the material diameter. In step S155, it is determined whether or not the fine grinding is completed, that is, step S122 of the machining program. If the fine grinding is not completed, the process returns to step S130, and if the fine grinding is completed, the processing ends.

In the second embodiment, if the quality of the grinding surface of the grinding wheel deteriorates, for example, during the rough grinding, the cutting completion diameter is corrected to finish the rough grinding earlier, and the fine grinding and the fine grinding are cut. By increasing the amount, the machining accuracy of the workpiece is improved. Further, if the quality of the grinding surface of the grinding wheel deteriorates, the machining accuracy of the workpiece is improved by, for example, slowing down the feed speed of the wheel head during the rough grinding.

Next, the third embodiment will be described. In this third embodiment, the main program of FIG. 3 is the same as that of each of the above-mentioned embodiments, but the grinding process for the first and second and subsequent products is different, and the second stage grinding process is not performed. Absent. This will be described with reference to FIGS.

When the first grinding process is started as in the case of the first embodiment, the grinding process according to the machining program shown in the flowchart of FIG. 15 is started. First C
In step S210, the PU 31 first calculates the following expression 7
Thus, the first rough grinding completion diameter D1 and the second rough grinding completion diameter D2
Is calculated.

[0054]

## EQU00007 ## D1 = D + U1 + 2.U2.N2 + 2.U3.N3 D2 = D + U2 + 2.U3.N3 However, D: Target finish diameter U1, U2, U3: At the first rough grinding, second rough grinding and fine grinding, respectively. Grinding wheel 1 per rotation of workpiece W
Depth feed amount of 9 (= grinding speed in each grinding / rotational speed of the workpiece W) N2: number of rotations required to make a ground surface Wa in a predetermined finishing state during the second rough grinding N3: minute The number of rotations required to form the surface to be ground Wa in a predetermined finished state during grinding, where D, the grinding speed during each grinding, the rotation speed of the workpiece W, and N2 and N3 are stored in the memory from the input device 40. The data is stored in 32, and U1, U2, and U3 are calculated by these data.

The CPU 31 calculates the first rough grinding completion diameter D1 and the second rough grinding completion diameter D2 as described above, and then, in a state in which the grinding wheel 19 and the workpiece W are rotated at a predetermined speed, in step S211. The grindstone base 13 is fast-forwarded and advanced to a position immediately before contacting the workpiece W (line E0 in FIG. 16). Next, in step S212, the CPU 31 sets the grindstone base 13
Is advanced at the preset first rough grinding feed rate to perform the first rough grinding of the workpiece W (line E1 in FIG. 16). In this case as well, similarly to each of the above-described embodiments, when the first rough grinding feed is applied to the grindstone base 13, the cutting feed position of the grindstone base 13 that changes momentarily is detected by the position detector 25, and the detected value is It is input to the CPU 31 via the sensor controller 42. Further, the tracing stylus 34a of the measuring device 24 is engaged with the ground surface Wa of the workpiece W, whereby the outer diameter of the ground surface Wa is measured in-process, and the measured value is the A-D converter 3
It is converted into a digital signal by 5 and input to the CPU 31.

When the first rough grinding progresses and the diameter of the surface to be ground Wa measured by the measuring device 24 reaches the first rough grinding completion diameter D1 calculated in step S210, the first rough grinding is completed (step S213), the grinding wheel base 13 is fast-forwarded and retracted by a predetermined amount (step S214, line E2 in FIG. 16), and the grinding wheel 19 is separated from the surface Wa to be ground. Then the whetstone stand 1
3 is advanced by the second rough grinding feed (step S215, line E3 in FIG. 16), and in parallel with this, the reduction of the machining diameter of the surface to be ground in step S217 is checked and step S218.
The whetstone base position correction is performed. This wheel head fast forward retreat,
The check of the reduction of the machining diameter of the surface to be ground and the correction of the wheel head position are substantially the same as steps S13, S16 and S17 of the first embodiment. The correction of the output signal value of the position detector 25 in order to eliminate the influence of the thermal displacement is performed by correcting the output signal value of the position detector 25 in the sensor controller 42, and after the second rough grinding that is subsequently performed. , This corrected output signal value is used.

When the second rough grinding progresses and the diameter of the surface to be ground Wa measured by the measuring device 24 reaches the calculated second rough grinding completion diameter D2, the CPU 31 completes the second rough grinding in step S216. Then, step S219
Then, the remaining grinding amount Z2 (measured value) at that time is taken out. The remaining amount of grinding Z2 is the diameter of the surface to be ground Wa measured by the measuring device 24 at the time of the completion of the second rough grinding, and the position of the wheel head 13 detected by the position detector 25 (correction of thermal displacement is made, and Value converted to the diameter of the ground surface Wa)
Is taken out as the difference.

In the following step S220, the CPU 3
1 calculates the retracted position F2 after the second rough grinding, and retracts the wheel head 13 to this retracted position F2. This retracted position F2
Is calculated as follows. Grinding of the same workpiece W or grinding of two consecutive workpieces W is performed by the grinding wheel 19
When the sharpness of No. has not changed so much, the remaining amount of grinding is proportional to the cutting feed amount of the grinding wheel 19 per one revolution of the workpiece, so the following Expression 8 is obtained.

[0059]

## EQU00008 ## Z2 / U2 = Z3 / U3 where Z2 and Z3: Grinding residual amount (converted to diameter) at the end of the second rough grinding and fine grinding, respectively. Then, this value is used as the predicted value Y3 of the remaining grinding amount at the end of the fine grinding that is subsequently performed.

[0060]

[Formula 9] Z3 = Z2 · U3 / U2 = Y3 The retracted position F2 of the wheel head 13 after the rough grinding is the predicted value Y.
It is calculated by the following Expression 10 using 3.

[0061]

[Equation 10] F2 = E2-Y3 / 2 However, E2: Position of the grinding wheel head 13 corresponding to the diameter of the grinding surface Wa measured by the measuring device 24 at the time of completion of rough grinding. Retreat position F2 based on the predicted value Y3 of the remaining grinding amount at the end of fine grinding
Is calculated, and the grindstone base 13 is retracted to the retracted position F2.

The operation state from the step of S218 grinding wheel position correction to the step S220 will be described with reference to FIG. In the second rough grinding, the position of the wheel head 13 detected by the position detector 25 decreases at a high cutting feed rate as indicated by the line E3, and the surface Wa to be ground is reduced.
Is ground by the grinding wheel 19, and the diameter of the grinding surface Wa measured by the measuring device 24 also decreases. Due to this high cutting speed, the remaining amount of grinding of the workpiece W rapidly increases. When the diameter of the grinding surface Wa detected by the measuring device 24 reaches the second rough grinding completion diameter D2 calculated in step S210, the grinding wheel head 13 is moved to the retracted position F as indicated by the line E4.
The remaining amount of grinding sharply decreases to 2 and becomes the predicted value Y3 of the remaining amount of grinding at the end of fine grinding. As a result, the work W is subjected to the bending necessary for the fine grinding, and when the grindstone 13 is fed by the fine grinding, the fine grinding of the work W is immediately started.

Returning to the continuation of the explanation of the flow chart of FIG. 15, the CPU 31 continues to step S220 and advances the grinding wheel base 13 from the retracted position F2 to carry out the fine grinding of step S221. In fine grinding, the position of the wheel head 13 decreases from the retracted position F3 at a low cutting feed rate as shown by the line E5 in FIG. 16, and the diameter of the grinding surface Wa measured by the measuring device 24 gradually decreases. When the fine grinding progresses and the diameter of the surface to be ground Wa reaches the finishing target diameter D, the CPU 31 determines that the fine grinding is completed in step S222, advances the control operation to step S223, and shows the line E6 in FIG. Then, the grindstone 13 is retracted to the original position and the machining program shown in the flowchart of FIG. 15 is ended.

At the time point when the second rough grinding in step S216 is completed, the measured value of the surface to be ground Wa by the measuring device 24 is D2 (= D + U2 + 2.U3.N3), but the shape of the surface to be ground Wa is as shown in FIG. It is part of a spiral as shown exaggeratedly. In this state, the distance between the rotation axis O of the workpiece W and the grinding point of the grinding wheel 19 is (D + 2 · U3 · N3) / 2, but the signal obtained from the measuring device 24 is D + U2 + 2.
・ U3 and N3. The diameter of the workpiece W when the workpiece W is rotated in this state to form a perfect circle indicated by the broken line is
D + 2 · U3 · N3. From this state, the measuring device 2
By the time the fine grinding is completed when the measured value of the ground surface Wa according to No. 4 reaches the target finishing diameter D, the number of rotations of the workpiece W required for producing the ground surface Wa in a predetermined finishing state during the fine grinding. It rotates about the same number of revolutions as N3.

When the first machining is completed as described above, the workpiece W is replaced with the next one, and the second and subsequent machining shown in step S6 of the main program of FIG. 3 are performed. The second and subsequent machining is performed by the in-process gauge machining program shown in the flowchart of FIG. 18 instead of FIG.

The flowchart shown in FIG. 18 shows steps S213 to S21 from the first grinding process shown in FIG.
5, S217 and S218 are omitted. That is, in the second and subsequent grinding processes, the wheel head position is not corrected by fast-forwarding and retracting the wheel head between the first rough grinding and the second rough grinding, and the rough grinding is performed only once. Instead, in order to correct the thermal displacement due to the temperature rising as the workpiece W is continuously machined before finishing the fine grinding and retreating the grindstone 13 fast-forwarding, the correction value is calculated and the grindstone position is corrected in step S222A. I do. This correction value calculation is performed by taking out the difference (see d in FIG. 21) between the outer diameter of the surface Wb to be ground measured by the measuring device 24 and the position of the wheel head 13 detected by the position detector 25 at the end of fine grinding. The position of the grinding wheel head is corrected by correcting the output value of the position detector 25 (the cutting feed position of the wheel head 13) by the sensor controller 42 by the difference. Fig. 16 shows the operating conditions for the second and subsequent grinding processes.
If it is indicated by, the grindstone rapid traverse in step S211 is line E.
0, line E1 and E3a for rough grinding in step S212, line E4a for receding in step S220, line E5a for fine grinding in step S221, and line E6a for grinding wheel head retreat in step S223.

According to the third embodiment, the grinding amount at the time of fine grinding is the minimum required value, and therefore the fine grinding time until the diameter of the surface to be ground Wa reaches the finishing target diameter D is short, but fine grinding is performed. The remaining grinding amount at the start is the predicted value Y3 of the remaining grinding amount at the end of fine grinding.
Therefore, the remaining amount of grinding converges to a substantially constant value during this short fine grinding time. Therefore, desired finishing conditions such as surface roughness and roundness of the surface Wa to be ground can be obtained. The amount of rough grinding increases as the amount of fine grinding decreases, but since the feed rate in rough grinding is large, the increase in rough grinding time is small.Therefore, variations in overall grinding time due to changes in the sharpness of the grinding wheel are significant. Is also small. Therefore, the cycle time for machining one workpiece is reduced and the variation in cycle time is reduced.

Next, the fourth embodiment will be described. In the fourth embodiment, the main program of FIG. 3 is the same as that in each of the above-mentioned embodiments, and the first and second steps of grinding are performed.
The first-stage first-stage grinding process is the same as in the third embodiment, and the second-stage grinding process is a contouring process by indirect sizing. Next, this will be described with reference to FIG.

As shown in FIG. 19, in the fourth embodiment, the grinding wheel 19 axially supported on the grindstone base 13 of the grinder used for the practical use has the moving direction Z of the work table 12 and the grindstone base 13 as shown in FIG.
Is driven to rotate about an axis inclined with respect to both the moving directions X, and the ground surface Wa and the ground surface Wb which are the outer peripheral surface of the workpiece W are ground by the grinding surface 19a parallel to the Z direction,
The grinding surface 19b, which is parallel to the X direction, grinds the end surface Wd to be ground.

In the first-stage grinding process of the fourth embodiment, the grinding surface Wa of the workpiece W is ground by the grinding surface 19a of the grinding wheel 19, and the in-process gauge of the first embodiment described above is used. Is substantially the same as the grinding process using.
That is, after first fast-feeding the grindstone base 13 and then applying the first rough grinding feed, the grinding surface 19a of the grinding wheel 19 is engaged with the surface Wa to be ground as shown by the alternate long and short dash line 19B to perform the first rough grinding. , The grindstone base 13 is once fast-forwarded and retracted, and then the second rough grinding feed is applied to correct the grindstone base position. Grinding surface Wa
If the diameter reaches the second rough grinding completion diameter D2 and the second rough grinding is completed, the retracted position F2 is calculated and the grinding wheel head 13 is reached to that position.
Back, then give a fine grinding feed to perform fine grinding,
When the diameter of the surface to be ground Wa reaches the finishing target diameter D and the fine grinding is completed, the grindstone base 13 is retracted to the original position.

Next, the contouring grinding of the surfaces Wb, Wd, We to be ground by the second step grinding will be described. The grinding wheel 19 returned to the original position 19A by the first-stage grinding process is positioned at a position 19C with respect to the workpiece W by moving the workpiece table 12 left by a predetermined amount. By feeding the work table 12 and the grindstone base 13 from this position, the grinding wheel 19 is fed in the V1 direction inclined with respect to the work W and moved to the position indicated by the chain double-dashed line 19D. In this position, the corner portion 19c of the grinding wheel 19 is located at the start position of the corner rounded portion We of the workpiece W, and the grinding surface 1
9b is cut into the ground surface Wd by a predetermined amount. By feeding the work table 12 and the grindstone base 13 from this position, the grinding wheel 19 is moved with respect to the work W along a predetermined arc V2 to a position indicated by a three-dot chain line 19E, and the corner rounded portion We Grinding is done. In the above operation, similarly to the grinding process by the indirect sizing in the case of the first embodiment, the work table 12 and the grindstone base 13 are fed based on (target position-current position). At the end of this period, the surface Wb to be ground is ground by the ground surface 19a,
After that, the grindstone base 13 is retracted.

In each of the above-described embodiments, after the completion of the first rough grinding of the in-process gauge machining program, the grindstone base 13 is once retracted to separate the grinding wheel 19 from the surface Wa to be ground of the workpiece W, At the initial stage of the second rough grinding that follows, the time when the grinding wheel 19 again contacts the surface Wa to be ground and starts grinding of its outer diameter is determined by the detection value of the measuring device 24.
Then, at this time, the workpiece W and the grindstone 1 are based on the feed position of the grindstone 13 detected by the position detector 25 and the outer diameter of the ground surface Wa measured by the measuring device 24.
3 is calculated, the feed position of the grindstone 13 detected by the position detector 25 is corrected by the thermal displacement calculated as described above, and the grindstone 1 thus detected
The error due to the thermal displacement of the feed position of 3 is compensated. Moreover, at the start of grinding when this correction is performed, there is almost no grinding resistance, so that the deflection of the workpiece W or the like is substantially zero.
Therefore, the error in the feed position of the grindstone base 13 due to the bending of the workpiece W or the like is removed, and the processing error due to such an error can be removed.

The amount of thermal displacement between the workpiece W and the grindstone 13 is detected between the first rough grinding and the second rough grinding of the in-process gauge machining program in the above-mentioned embodiment. It may be done at other times as long as it is being processed by the process gauge.

The contact between the workpiece and the grinding wheel is detected by detecting the decrease in the diameter of the workpiece by the measuring device 24 in the above-mentioned embodiment, but a strain gauge is attached to the center of the tailstock. The strain gauge may detect the deflection of the center at the time of contact. Further, an AE sensor may be attached to the grinding wheel to detect a sound generated during grinding. Furthermore, a voltmeter for detecting the load of the grinding wheel drive motor may be attached, and a change in the voltmeter may be determined as contact between the grinding wheel and the workpiece.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a grinding apparatus according to the present invention.

FIG. 2 is a diagram showing an overall configuration common to each embodiment of the grinding apparatus according to the present invention.

FIG. 3 is a flowchart showing an example of a main program for controlling the entire first embodiment of the grinding apparatus according to the present invention.

FIG. 4 is a flowchart showing a machining program for an in-process gauge used for machining the first workpiece in the first embodiment.

FIG. 5 is a flowchart showing a correction value calculation program used in the first embodiment.

FIG. 6 is a flowchart showing a machining program for indirect sizing used in the first embodiment.

FIG. 7 is a flowchart showing an in-process gauge machining program used for machining the second and subsequent workpieces in the first embodiment.

FIG. 8 is an explanatory diagram of the overall operation of the first embodiment.

FIG. 9 is an explanatory diagram of an operation of the first embodiment.

FIG. 10 is an explanatory diagram of a relationship between a wheel head position and a diameter of a surface to be ground in the grinding device.

FIG. 11 is a flowchart showing a part of an in-process gauge processing program used in the second embodiment.

FIG. 12 is a flowchart showing the remaining part of the in-process gauge machining program used in the second embodiment.

FIG. 13 is a flowchart showing a part of a calculation check correction program used in the second embodiment.

FIG. 14 is a flowchart showing the remaining part of the calculation check correction program used in the second embodiment.

FIG. 15 is a flowchart showing a machining program for an in-process gauge used for machining the first workpiece in the third embodiment.

FIG. 16 is an explanatory diagram of the overall operation of the third embodiment.

FIG. 17 is an explanatory diagram showing a surface to be ground and its vicinity at the time of completion of rough grinding in the third embodiment.

FIG. 18 is a flowchart showing an in-process gauge machining program used for machining the second and subsequent workpieces in the third embodiment.

FIG. 19 is an explanatory diagram of a main part of the fourth embodiment.

FIG. 20 is an explanatory diagram of the operation of the conventional grinding device.

FIG. 21 is a diagram showing a main part of an example of a grinding device targeted by the present invention.

[Explanation of symbols]

13 ... Grinding stone base, 19 ... Grinding wheel, 100 ... Driving means, 11
0 ... Position detecting means, 120 ... Measuring means, 130 ... Judging means, 140 ... Calculation means 1, 150 ... Correction means, 160 ...
Control means, W ... Workpiece, Wa ... Surface to be ground.

Claims (1)

[Claims] 1. A grindstone base having a grindstone wheel driven to rotate by a motor, and a drive means for relatively moving the grindstone base and the workpiece in a direction in which the grindstone wheel and a workpiece to be ground by the grindstone wheel move toward and away from each other. Position detecting means for detecting the position of the grindstone base with respect to the workpiece, measuring means for measuring the outer diameter of the surface to be ground of the workpiece during grinding, and the driving means to operate the workpiece by the grinding wheel. The outer diameter of the surface to be ground is ground, and in the course of this grinding, the grindstone base is once retracted with respect to the workpiece to separate the grindstone from the workpiece, and then it is moved forward again to move the workpiece by the grindstone. Judgment for determining the time when the grinding wheel is brought into contact with the workpiece due to the advance of the grinding wheel head after the retreat based on the control means for performing grinding again and the detected value of the outer diameter of the surface to be ground of the workpiece by the measuring means Means and this format Based on the outer diameter of the ground surface of the workpiece measured by the measuring means and the position of the grindstone detected by the position detecting means at the time when it is determined that the grinding wheel and the workpiece have contacted each other And a correction unit that corrects the position of the grinding wheel head detected by the position detection unit based on the thermal displacement amount calculated by the calculation unit. A grinding device characterized by the above.