JPS61252069A - Device for controlling surface grinding machine - Google Patents

Abstract

PURPOSE:To improve machining accuracy of a standard size machining allowance in a preceding grinding while eliminate a dimensional error in measurement due to thermal deformation of workpiece and gauge, and improve measuring accuracy by providing a gauge means in a following grinding station. CONSTITUTION:Change in the machining dimension of a workpiece W is measured in order on carrying out a finishing grinding by means of a gauge 14 in a finishing grinding station C and, based on this measured signal, a feed motor 12b in the finishing station C is controlled in its driving by means of a controller 16b, to feed a wheel spindle 10. When the machining dimension has reached a certain second dimension H2, the feed of the wheel spindle 10 by the motor 12b is stopped. The machining dimension H1 of a workpiece W after a rouge grinding and before a finishing grinding, is measured by the gauge means 14 and, based on the signal of this measurement, a controller 16a makes adjusting control of the operating quantity of a feed motor 12a in a rough grinding station B, for the first dimension H1 in machining the following workpiece W, to improve accuracy in standard size machining of the following workpiece W.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a control device for a surface grinder that continuously performs pre-grinding and post-grinding such as rough grinding and finish grinding at separate stations. .

(Prior art) In general, for example, in a surface grinder that rotates a semiconductor plate as a workpiece and grinds its surface with a grinding wheel, the grinding process is performed continuously in the order of rough grinding, finish grinding, fine finish grinding, etc. The material is then processed to the specified dimensions. In this case, as seen in Utility Model Application No. 58-8563, the distance between the workpiece and a standard gauge that indicates the machining height of the workpiece placed on the table is measured alternately with a non-contact distance meter, and each A known technique is to stop grinding when the values match, thereby dealing with wear of the grinding wheel.

However, when measuring machining dimensions while grinding as described above, the workpiece heats up due to machining, and the workpiece is deformed by this heat, so measurements are taken while machining. It does not match the actual dimensions in the current state, and there is a problem with measurement accuracy. This problem is especially noticeable in rough grinding because the rotation is high and the amount of grinding is large.

In addition to the non-contact type gage means for measuring the machining dimensions of a workpiece, there are also gage means that measure by directly contacting the machining surface of the workpiece. In addition to the deformation caused by the temperature rise of the workpiece, the measurement accuracy is affected by the temperature rise of the gauge, and there is a risk that machining dimensional errors may become large.

Furthermore, when multiple stages of grinding are performed continuously as described above, it is preferable to carry out sizing processing without measuring the machining dimensions in the previous stage of grinding, as this simplifies the control mechanism. However, the machining accuracy at this preliminary stage affects the final machining dimensional accuracy, and it is desirable to improve that accuracy.

(Objective of the Invention) In view of the above circumstances, the present invention provides a method for continuously processing pre-grinding such as rough grinding and post-grinding such as finish grinding in separate stations, in which the surface of the workpiece is grinded to a fixed size. The surface grinding machine side wJ device is designed to improve the machining degree of the dimensional machining allowance by measuring with a gauge means installed in post-processing, and eliminate the measurement accuracy of dimensional errors caused by thermal deformation of the workpiece and gauge in the measurement. The purpose is to provide

(Structure of the Invention) The surface grinding machine control device of the present invention includes a gauge means for measuring the machined dimensions of the workpiece in the post-grinding station, and the gauge means measures the machined dimensions of the workpiece during post-grinding, and also measures the machined dimensions of the workpiece during the pre-grinding. The present invention is characterized in that a grinding control means is provided for measuring the machining dimensions of the subsequent workpiece before post-grinding and correcting the sizing machining allowance for pre-grinding based on the measured value.

(Effects of the Invention) According to the present invention, in a post-grinding station such as finish grinding, grinding is performed while measuring the machining dimensions of the workpiece with a gauge means, thereby obtaining accuracy of the post-grinding and By using the gauge means in the grinding station to measure the machining dimensions of the workpiece after pre-grinding such as rough grinding, and modifying the pre-grinding station's machining allowance based on the measurement, the machining allowance for the next workpiece is adjusted. The accuracy of sizing processing can be improved. This improves the accuracy of post-processing, and ultimately enables good grinding.

In addition, since the machining dimensions of the workpiece after the pre-grinding are measured while the workpiece temperature is low, measurement errors due to thermal deformation of the workpiece and gauge are small, and the measurement accuracy is good and machining accuracy is high. will improve. Further, the pre-processing can be controlled by a gauge means provided in the post-processing station, and together with the fact that the pre-processing is fixed-size processing, the structure and control can be simplified.

<Example) Hereinafter, the present invention will be explained in detail with reference to the drawings.

FIG. 1 is a schematic plan view of a surface grinder, FIG. 2 is a schematic side view of a grinding station, and FIG. 3 is a schematic configuration diagram of a control system.

The surface grinder is equipped with a disc-shaped index table 1,
The index table 1 is rotatably supported by a rotary shaft 2 located below the center, and this rotary shaft 2 is driven to rotate intermittently at predetermined angles by a drive mechanism 3. Six work rotary tables 4 are arranged concentrically and equally spaced on this index table 1, and the rotary shaft 6 of the work rotary tables 4 is rotatably supported by a support base 5 fixed to the index table 1. and this work rotary table 4
A flat workpiece W is placed on the upper surface of the workpiece.

Each work rotation table 4 is sequentially moved through processing stations A to F by index rotation of the index table 1 by 60 degrees by the drive mechanism 3. 1st
Station A is a loading station,
A workpiece W is placed on the workpiece rotation table 4. The second station B is a rough grinding station, and performs rough grinding using a grinding amount M8a disposed above the index table 1. The third station C is a finish grinding station, and similarly performs finish grinding by a grinding device 8b disposed above the index table 1. The fourth station D is a fine finish grinding station, and similarly performs fine finish grinding using a grinding device 8C disposed above the index table 1. The fifth station E is a workpiece cleaning station, and cleans the workpiece W after grinding. The sixth station F is a work rotation table cleaning station, and cleans the work rotation table 4 after seven unloading of the work W.

In the grinding devices 8a to 8C disposed above the second to fourth stations B to D, respectively, a grinding wheel shaft 10 having a grinding wheel 9 suitable for each grinding process at its tip is rotated by a drive motor 11 at a predetermined level. Each feed motor 12a-+20 is rotated by a number of motors 12a-+20 and
By rotating the screw shaft 13 and moving the grindstone shaft 10 up and down by a predetermined dimension, the surface of the workpiece W is ground to a predetermined dimension.

Further, the finish grinding station C and the fine finish grinding station D are each provided with gauge means 14 and 15 for measuring the machining dimensions of the workpiece W. The operation of the feed motors 12a to 12c of each of the grinding stations BD is controlled by a grinding control means 7 which receives signals from the gauge means 14, 15, and the work W is sequentially ground to a predetermined machining size.

The grinding of the workpiece W by each of the grinding stations B to D is as shown in FIG. 4. The rough grinding station B performs pre-grinding on the workpiece W from the material dimension H8 to the first dimension H1. Yes, the finish grinding station C as post-grinding cuts the workpiece W to the first dimension H! Finish grinding is performed while measuring the machining dimensions from to the second dimension H2 using the gauge means 14. Further, the fine finishing station D changes the workpiece W from the second dimension H2 to the third dimension H.
3, that is, precision grinding is performed while measuring the machining dimensions with the gauge means 15 to the final product dimensions. The gauge means 14.15 provided in the finishing and precision grinding station C9O includes first gauges 14a, 15 for measuring the height of the workpiece mounting surface 4a of the workpiece rotary table 4.
a and the second gauge 14 that measures the height of the machined surface of the workpiece W
b and 15b, and the machining dimensions of the workpiece W are measured from the difference between the two.

Each feed motor 12a to 1 of the grinding station B-0
2C has a controller 1 that controls each feed amount.
68 to 16c are attached, and the controllers 16a to 1
A measurement signal from the gauge means 14 or 15 is output to 6C. That is, the measurement signal of the gauge means 14 provided in the finish grinding station C is transmitted to the controller 16b of the feed motor 12b of the finish grinding station C.
It is also output to the controller 16a of the feed motor 12a of the rough grinding station B. The gauge means 14 of the finish grinding station C sequentially measures changes in the machined dimensions of the workpiece W during finish grinding, and when the machined dimensions reach a predetermined second dimension 1''2, the gauge means 14 starts the finish grinding. This is to stop the feed of the grindstone shaft 10 by the feed motor 12b. In addition, the gauge means 14 of the finish grinding station C measures the machining dimension Hx of the workpiece W during finish grinding after rough grinding, outputs the signal to the controller 16a of the rough grinding station B, and outputs the signal to the controller 16a of the rough grinding station B. This is to correct and control the operation m of the feed motor 12a with respect to the first dimension Hi during processing of the workpiece W.

On the other hand, the gauge means 15 of the fine finishing station D measures the machined dimensions of the workpiece W during fine finishing grinding at this station, and stops the feed of the feed motor 12c when the predetermined finished dimension 1''3 is reached. It is.

Regarding the measurement by the gauge means 15 of this fine finishing station D, the machining dimension H2 of the workpiece W after finish grinding is measured and a measurement signal is sent to the controller 16b of the feed motor 12b of the finish grinding station C in the same manner as described above. It is also possible to output it and perform feedback control of the feed end at the finish grinding station C.

The above control basically compares the measurement dimension of the gauge means 14 with the currently set fixed size position of rough grinding, that is, the first processing dimension H1, and when the measured processing dimension is larger than the set dimension, the set dimension is is corrected in the negative direction, while when it is small, the set dimension is corrected in the positive direction, and when it is equal, no correction is necessary.

Further, as shown in FIG. 2, the rotary shaft 6 of the work rotary table 4 has a driven gear 17 attached to the lower end thereof passing through the support base 5. On the other hand, in the second to sixth stations B to F, permanent motors 18a to 18e for rotationally driving the work rotary table 4 are installed at fixed portions of the lower outer periphery of the index table 1, respectively. A drive gear 19 that can mesh with the driven gear 17 is provided on the output shaft of the drive gear.

The rotation speed of the permanent motors 18a to 18e is controlled so as to obtain the required rotation speed of the work rotation table 4 during processing at each station 8-F, and the drive mechanism 3 controls the rotation speed of the index table 4.
When indexing and rotating, it is controlled to rotate at a low speed. Rough grinding at 2nd station B, 3rd station C
In the finish grinding at the fourth station D and the fine finish grinding at the fourth station D, the rotational speed of the work rotary table 4 during grinding is controlled to decrease in the order of rough grinding, finish grinding, and fine finish grinding. Further, in the cleaning stations of the fifth station E and the sixth station F, the work rotation table 4 only needs to rotate during cleaning, and the cylinders of the permanent motors 18d and 18e are connected to the permanent motors 18d and 18e of the grinding station. A motor smaller than motors 18a-18c is used. Furthermore, when indexing and rotating the index table 1, if the permanent motors 18a to 18e are rotated slowly, as the index table 1 rotates, the driven gear 17 of the work rotation table 4 is rotated by the permanent motors 18a to 18e of the previous station. The station can be disengaged from the drive gear 19 of the station, and can smoothly mesh with the drive gear 19 of the permanent motors 18a to 18e of the next station.

Next, FIG. 5 is a plan view of the index table 1 and its drive mechanism 3, and FIG. 6 is a sectional side view of the index table 1 showing only the work rotation table 4 in the grinding station B.

The index table 1 is supported by a rotating shaft 2, and the outer peripheral part is supported by an annular support member 20,
This support member 20 is fixed to a fixed part by fixed legs 20a between each station A-F. In the driving machine 13, the rotating shaft 2 of the index table 1 is linked to a Geneva mechanism 21, a worm wheel 22 is fixed to the lower end of the shaft 21a of the Geneva mechanism 21, and a cam body 24 facing the proximity switch 23 is attached to the upper end. is provided. A worm shaft 25 that meshes with the worm wheel 22 is supported in the horizontal direction, and an output gear 28 of an indexing motor 27 meshes with a gear 26 at the end of the worm shaft 25.

The rotation of the indexing motor 27 is decelerated by gears 26, 28 and worms 22, 25 and transmitted to the Geneva mechanism 21. When the shaft 21a rotates once, the index table 1 rotates 60 degrees, and the cam body 24 approaches. The switch 23 is actuated to stop the operation of the indexing motor 27 and complete indexing rotation of the index table 1.

Further, the rotation shaft 6 of the work rotation table 4 is connected to a support base 6.
The driven gear 17 is attached to the lower end of the shaft. The permanent motor 18a is attached to a support plate 34 on the fixed side, and is provided with a drive gear 19 that meshes with the driven gear 17. An upper flange 5a of the support base 5 is fixed to the index table 1. Further, a suction passage (not shown) is formed through the rotary shaft 6 of the work rotary table 4 in the direction of the central axis, and the upper end of this suction passage is opened to the upper end mounting surface 4a of the work rotary table 4. It communicates with the suction groove and suction hole.

A suction force introduction mechanism 35 is disposed below the rotary shaft 6, and a suction cup member 38 that moves up and down attracts the lower end of the rotary shaft 6 and introduces suction force to the mounting surface of the workpiece rotary table 4.
The workpiece W is held by suction on a.

Note that the gauge means 14, 15 may be a non-contact type gauge. Further, the number of machining stations in the above-mentioned embodiments is designed to be changed as appropriate in response to changes in the conditions of surface grinding, and the specific structure and the like are also changed.

[Brief explanation of drawings]

Fig. 1 is a plan view showing a schematic configuration of a surface grinder according to an embodiment of the present invention, Fig. 2 is a cross-sectional side view taken along line I[-■ in Fig. 1 showing the grinding station, and Fig. 3 is a control A schematic configuration diagram of the system; Figure 4 is an explanatory diagram showing the grinding dimensions of a workpiece by each grinding station; Figure 5 is a partially sectional plan view showing a specific structural example of the index table and its drive mechanism; FIG. 6 is a cross-sectional side view of the index table with the work rotation table partially omitted. 1... Index table 4... Work rotation table 7... Grinding control means

Claims (1)

[Claims] (1) In a surface grinding machine that performs pre-grinding at a pre-grinding station for grinding the work surface to a fixed size and actuator grinding at a post-grinding station in separate stations, A gauge means is provided to measure the machined dimensions of the workpiece during post-grinding at the grinding station, and the machined dimensions of the workpiece after pre-grinding at the pre-grinding station are measured by the gauge means of the post-grinding station before post-grinding. A surface grinding machine control device comprising a grinding control means for correcting a pre-grinding sizing allowance based on a value.