JP2004268224A - Polishing device, work processing method and work processing process control system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To monitor processing accuracy in a preprocessing process in a polishing device. <P>SOLUTION: This polishing device performing the polishing of a work 3 has a means for detecting the residual quantity R of stock to be removed, and a means for determining the working accuracy in the preprocessing process performed before the polishing process on the basis of the residual quantity. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a polishing apparatus, a work processing method, and a work processing control device.
[0002]
[Prior art]
In a production line including a polishing step, it is required to improve the cycle time of the polishing step (for example, see Patent Document 1).
Various measures have been taken to improve cycle time and processing quality, but at present the effects are not as high as expected.
[0003]
[Patent Document 1]
Japanese Patent Publication No. 6-69663 (page 1)
[0004]
[Problems to be solved by the invention]
The inability to sufficiently improve the cycle time and processing quality is affected not only by the problem of the polishing process, but also by the quality of the heat treatment and the turning process, which are the preceding processes.
6 and 7 show the relationship between the quality of the previous process and the cycle time in the polishing process. FIG. 6A shows a workpiece 100 having a small remaining amount and a good roundness among the workpieces to be polished (inner surface polishing). The uneven thickness and the irregularity of the target surface 100b are reduced. On the other hand, FIG. 6B shows an object 101 having a poor roundness, in which the remaining amount of the machining allowance is large and the uneven thickness and the irregularity of the processing target surface 101b are larger than the final polishing shape 101a.
[0005]
FIG. 7A shows a measurement result of the grinding force of the work 100 shown in FIG. 6A, and FIG. 7B shows a measurement result of the grinding force of the work 101 shown in FIG. As can be seen from FIGS. 6 and 7, when the remaining amount of the stock is large (uneven thickness and large irregularity), a large cycle time is required in the subsequent polishing process. In particular, in FIG. 7, T1 <T2. If the roundness is poor due to uneven wall thickness or irregularity, intermittent processing is performed, and the quality of the quality is deteriorated due to large damage to the grindstone.
[0006]
In order to solve the above-mentioned problems, it is important to grasp the size and variation of the remaining stock.
Therefore, an object of the present invention is to monitor processing accuracy in a pre-processing step in a polishing apparatus.
[Means for Solving the Problems]
The present invention provides a polishing apparatus for performing a polishing process on a work, wherein a remaining amount of remaining stock detecting means for detecting a remaining amount of work allowance, and a pre-processing performed before the polishing step based on the remaining amount of work allowance. Determining means for determining the processing accuracy in the process.
If the remaining amount of work allowance in the pre-processing step is large (uneven thickness and large irregularities), a large amount of cycle time is required in the polishing step, which is the next processing step. If the remaining amount is large, it can be determined that the processing accuracy in the pre-processing step is low.
[0008]
It is preferable that the surplus remaining amount detection means detects a remaining amount of the work allowance from a difference between a final cutting position of a grindstone to be polished and an initial contact position between the grindstone and the work.
It is preferable that the determination unit determines the processing accuracy of the pre-processing step based on an average value or a deviation of the remaining stock amounts of a plurality of workpieces. Note that the stability of the pre-machining process can be determined by calculating the deviation of the remaining stock amount.
[0009]
The work processing method according to the present invention includes a polishing step of performing polishing on the work, a pre-processing step performed before the polishing step, and a step of detecting a remaining work allowance in the polishing step. Determining the machining accuracy in the pre-machining step based on the remaining amount of the work allowance, and adjusting the machining conditions in the pre-machining step. Here, the pre-processing step is, for example, a work cutting step and / or a heat treatment step. Detecting the remaining machining allowance in the polishing process reveals the machining accuracy in the pre-machining process, and based on this, adjusts the machining conditions in the pre-machining process to achieve the optimal remaining machining allowance and shorten the cycle time of the polishing process Alternatively, stability can be achieved.
[0010]
The work process control apparatus according to the present invention is an apparatus for controlling a work processing process including a polishing step of polishing a work, and a pre-processing step performed before the polishing step, wherein Means for detecting the remaining amount of work allowance in the process, and means for determining the machining accuracy in the pre-machining step based on the remaining amount of work allowance and adjusting the machining conditions in the previous process. And Detecting the remaining machining allowance in the polishing process reveals the machining accuracy in the pre-machining process, and based on this, adjusts the machining conditions in the pre-machining process to achieve the optimal remaining machining allowance and shorten the cycle time of the polishing process Alternatively, stability can be achieved.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a configuration example of a main part of a polishing apparatus according to an embodiment. The polishing apparatus 1 controls a drive mechanism 2 for rotating and driving the grindstone 1, a support mechanism 4 for supporting a bearing inner ring material 3 as a work (circular work), and a drive control for these mechanisms 2 and 4. And a control unit 5 as a control unit for performing the control.
[0012]
This polishing apparatus is used in a polishing step, which is one of processing and assembling steps of the work 3. The polishing step is performed as a final processing step of the processing step of the work. The work processing step includes a material preparation / shaving step (heat treatment / turning step) as a pre-processing step before the polishing step.
[0013]
The drive mechanism 2 of the polishing apparatus is configured to be slidable in the left-right direction in FIG. 1. When the inner ring material 3 is polished, the drive mechanism 2 moves as shown by a broken arrow in FIG. 1. This is a processing position where the outer peripheral surface of the grindstone can be brought into contact with the inner peripheral surface 3a of the work as the processing surface. In addition, by moving the drive mechanism 2 to the retracted position shown in FIG. 1, the replacement of the grindstone 1 and the work 3 can be easily performed.
[0014]
The drive mechanism 2 has a wheel head (hereinafter simply referred to as “W / H”) 21 on which one end of the grindstone 1 is detachably mounted and rotatably supported by bearing means (not shown). / H21 is provided. The electric motor 22 is configured by an AC motor driven by an inverter or the like. A first pulley 23 and a second pulley 24 are attached to the other end of the W / H 21 and the output shaft of the electric motor 22 so as to be integrally rotatable. A belt body 25 is bridged between the first and second pulleys 23 and 24. In the drive mechanism unit 2, when the motor 22 rotates in response to an operation command from the control unit 5, The rotational force is transmitted to the W / H 21, and the W / H 21 and the grindstone 1 are driven to rotate at a constant speed in the direction P in FIG.
[0015]
The support mechanism 4 of the polishing apparatus includes a cutting table 41 and a cutting motor 42 connected to the cutting table 41 via a ball screw type coupling mechanism (not shown). The motor 42 rotates in response to a speed command to the motor 42 so that the cutting speed (polishing speed) of the grindstone 1 with respect to the work 3 can be changed. More specifically, the cutting table 41 includes a magnet chuck that holds the work 3 in a rotatable state and a work rotation motor that rotates the work 3 held by the magnet chuck in the Q direction in FIG. (Not shown). When the cutting motor 42 rotates in the direction R in FIG. 1, the cutting table 41 is moved in the direction S in FIG. Thereby, the rotating work 3 is also pushed in the S direction along with the movement of the cutting table 41, and the contact (polishing) position between the processing surface 3a and the grindstone is moved in the S direction. As a result, the cut amount (polishing amount) of the grindstone 1 with respect to the processing surface 3a is changed, and the polishing speed (cutting speed) of the grindstone 1 is also changed by changing the rotation speed of the cutting motor 42.
[0016]
The control unit 5 of the polishing apparatus is constituted by a CPU, a memory, and the like, and performs each step (indexing, semi-urgent, black scale, rough, finish, and finish SP (spark out)) in the polishing process according to a program. ing.
The control unit 5 has a function of detecting the remaining amount of the stock of the workpiece 3 during the polishing process, monitoring the processing accuracy in the pre-machining process, and is also a remaining stock calculating unit.
[0017]
A method of acquiring the remaining amount of the stock will be described with reference to FIGS. First, the processing of the control unit 5 regarding the calculation of the remaining amount R is roughly divided into the calculation of the final cutting position Y (steps S1 and S2), the acquisition of the initial contact position Z between the grinding wheel 1 and the work 3 (S5), There is a calculation of the remaining stock R (step S6). Since the remaining amount R can be obtained as a difference between the final cutting position Y by the grindstone 1 and the initial contact position Z between the grindstone 1 and the work 3, the remaining amount R is obtained by calculating the positions Y and Z. You can ask. In FIG. 3, the function as the remaining amount calculating unit is indicated by a frame surrounded by a dotted line.
[0018]
To obtain the final cutting position, first, the total cutting amount X of the grinding wheel 1 is calculated (step S1). The total cutting amount X is the total of the cutting amounts in the respective steps in the polishing process, and specifically, is the total of the cutting amounts in the indexing, semi-express, black scale, coarse, and finishing steps. However, in this case, since the cutting origin position O is set at the center of the grinding wheel, the total cutting amount X includes the grinding wheel diameter. Therefore, the total cutting amount X is obtained as "X = indexing amount + quasi-rapid amount + black scale amount + rough amount + finishing amount + grinding wheel diameter".
Since the final cutting position Y is a position away from the origin O by a total cutting amount X, it can be calculated based on the total cutting amount X. However, in this case, since the offset value due to the deviation between the center of the grinding wheel and the origin position is also considered, the final cutting position Y = X + the offset value.
[0019]
After that, the control unit 5 starts the polishing process (step S3), and upon detecting the contact between the grindstone 1 and the work 3, acquires the position as the initial contact position Z (step S5). The difference between the last calculated cutting final position Y and the acquired initial contact position Z is the remaining amount of allowance R, which can be calculated as R = YZ (step S6). The surplus remaining amount R obtained by the calculation is displayed on a monitor and registered in a history register (remaining surplus remaining amount storage unit) of the control unit 5 (step S7). As described above, the polishing apparatus also has a function of storing the remaining stock amount of a plurality of workpieces.
[0020]
The history register stores the remaining amount of stock removal of each work, and the control unit 5 monitors and displays data of the remaining stock amount R of the polished work. In this manner, the polishing apparatus also has a function of displaying the remaining stock amount.
For example, a graphical display of the history of the remaining stock R for a predetermined number of polished works (for example, 100) and / or a numerical display of a history of the remaining stock for a predetermined number of polished works (for example, 10) is performed. . Therefore, the operator can monitor the processing accuracy of the pre-processing step by monitoring and displaying the remaining amount data of the stock removal of the polished work.
[0021]
Further, the control unit 5 calculates an average value (x) and a deviation (σ) for every N pieces of the remaining amount of surplus remaining data (N can be set). If the average value of the remaining stock R exceeds a predetermined threshold value (set by the user), the control unit 5 determines that the remaining stock is too large, and issues a warning message prompting confirmation of the accuracy of the pre-machining process. indicate. When the deviation of the remaining stock R exceeds a predetermined threshold value (set by the user), the machining stability of the pre-machining process is low, and the average value of the deviation is equal to the predetermined threshold value ( If the value exceeds (set by the user), a warning message for prompting confirmation of the accuracy of the pre-processing step is displayed. As described above, the polishing apparatus also has a processing accuracy determination and / or warning function in the pre-processing step.
[0022]
As shown in FIG. 4, when the data related to the remaining amount of the stock exceeds the threshold value, the user adjusts and confirms the pre-processing step (setting of the processing conditions of the heat treatment / turning step, etc.) and checks the threshold value. By obtaining the following optimum remaining amount of machining allowance, the machining accuracy of the pre-machining process can be promptly improved, and the polishing cycle time can be shortened and stabilized.
As for the adjustment and confirmation of the pre-machining step, for example, in the case of the turning step, the cause is pursued and adjusted so as to obtain an appropriate machining allowance, and the turning amount is adjusted and the turning condition set value is reviewed. In the case of the heat treatment step, the cause is pursued and adjusted so that the distortion due to the heat treatment does not occur, and the set value of the heat treatment condition is reviewed.
In the case where the polishing process is performed by a batch process or the like, the history of the remaining amount of the stock removal may be used as statistical data for improving the quality of the pre-processing process to improve the quality over a long period of time.
[0023]
FIG. 5 shows an embodiment of the work processing control device of the present invention. The control device 51 includes, in addition to the control unit 5 described above, a processing condition adjustment unit 52 that automatically adjusts processing conditions to a device for a pre-processing step. When the amount exceeds the threshold value, the adjustment unit 52 automatically adjusts the pre-machining process to improve the machining accuracy and performs feedback so that an appropriate remaining amount of the stock can be obtained.
[0024]
【The invention's effect】
According to the present invention, the processing accuracy of the pre-processing step can be monitored based on the remaining amount of the stock removal.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a polishing apparatus.
FIG. 2 is a positional relationship diagram between a grindstone and a work.
FIG. 3 is a flowchart of a remaining reserve amount acquisition.
FIG. 4 is an explanatory diagram of processing condition adjustment feedback for a pre-processing step.
FIG. 5 is a configuration diagram of a work processing control device.
FIG. 6 is a diagram showing the roundness of a work.
FIG. 7 is a graph showing a result of grinding force measurement.
[Explanation of symbols]
3 Work 5 Control Unit 51 Work Processing Process Control Device 52 Processing Condition Adjustment Unit

Claims (6)

In a polishing apparatus that performs a polishing process on a work,
A stock removal amount detecting means for detecting a work stock remaining amount;
Determining means for determining processing accuracy in a pre-processing step performed before the polishing step, based on the remaining amount of the work allowance,
A polishing apparatus comprising: 2. The polishing apparatus according to claim 1, wherein said remaining amount of remaining stock detecting means detects a remaining amount of work remaining from a difference between a final cutting position of a grindstone to be polished and an initial contact position between said grindstone and the work. 3. The polishing apparatus according to claim 1, wherein the determination unit determines the processing accuracy of the pre-processing step based on an average value or a deviation of the remaining machining allowances of the plurality of workpieces. 4. In a work processing method including a polishing step of polishing the work, and a pre-processing step performed before the polishing step,
A step of detecting the remaining amount of work allowance in the polishing step,
A step of determining processing accuracy in the pre-processing step based on the remaining amount of the work allowance, and adjusting a processing condition of the pre-processing step;
A workpiece processing method comprising: 5. The work processing method according to claim 4, wherein the pre-processing step is a work cutting step and / or a heat treatment step. An apparatus for controlling a work processing process including a polishing step of performing polishing on a work, and a pre-processing step performed before the polishing step,
Means for detecting the remaining work allowance in the polishing step,
A means for determining processing accuracy in the pre-processing step based on the remaining amount of the work allowance and adjusting processing conditions in the previous step;
A work machining process control device comprising:

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