JPH0244670B2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a control device for a surface grinding machine 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 Publication 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 the machining dimensions while grinding as described above, the workpiece heats up due to machining, and the workpiece is deformed by this heat. This does not match the actual dimensions after processing, 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 gauge means mentioned above, there are also gauge means for measuring the machining dimensions of the workpiece.
There are gauges that measure by directly contacting the machined surface of the workpiece, and with such contact type gauges, in addition to deformation due to the workpiece's temperature rise, the measurement accuracy is affected by the temperature rise of the gauge, and the machining accuracy is affected. Dimensional errors may become large.

Furthermore, when multiple stages of grinding are performed continuously as described above, the control mechanism also allows for sizing processing in which grinding is performed at a predetermined control amount without measuring the machining dimensions in the previous stage of grinding. Although this is preferable because it is simple, the machining accuracy in the previous stage affects the final machining dimensional accuracy, and it is desirable to improve that accuracy.

(Object 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 a workpiece is ground at a predetermined controlled amount. The accuracy of machining to the set dimensions determined as the machining allowance for the workpiece is improved by measuring with a gauge means installed in post-processing, and the measurement accuracy of dimensional errors due to thermal deformation of the workpiece and gauge is eliminated in the measurement. It is an object of the present invention to provide a surface grinding machine control device as described above.

(Structure of the Invention) The surface grinding machine control device of the present invention is provided with a gauge means for measuring the machined dimensions of the workpiece in the post-grinding station, and performs post-grinding while measuring the machined dimensions of the workpiece with the gauge means. , measure the machining dimensions of the workpiece after pre-grinding before post-grinding, compare this measured value with the set dimension determined as the machining allowance for the workpiece during pre-grinding, find the dimensional difference, and set the current setting on the pre-grinding station. The present invention is characterized in that a grinding control means is provided for correcting the machining allowance by the above-mentioned dimensional difference.

(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 a workpiece using a gauge means, thereby obtaining accuracy in the post-grinding, and By measuring the machining dimensions of the workpiece after pre-grinding such as rough grinding using the gauge means of the post-grinding station, and correcting the machining allowance set in the pre-grinding station based on the measurement, By compensating the control amount for pre-grinding of the next workpiece, it is possible to improve the machining accuracy to the set dimensions. This improves the accuracy of post-processing, and ultimately enables good grinding.

In addition, since the machining dimensions of the workpiece after 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 the machining accuracy is will improve. Furthermore, the pre-processing can be controlled by a gauge means installed in the post-processing station, and this pre-processing is a fixed-size process in which grinding is performed at a predetermined controlled amount without measuring the process dimensions.This, combined with the fact that the structure is simple, This makes it possible to simplify the process and control.

(Example) Hereinafter, an example of the present invention will be described 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 has a disc-shaped index table 1.
The index table 1 is rotatably supported by a rotary shaft 2 at the bottom of the center, and this rotary shaft 2 is driven to rotate intermittently at predetermined angles by a drive mechanism 3. Six workpiece rotary tables 4 are arranged concentrically and equally spaced on this index table 1, and the workpiece rotary tables 4 have their rotational shafts 6.
is rotatably supported by a support base 5 fixed to the index table 1, and a flat workpiece W is placed on the upper surface of the workpiece rotary table 4.

Each work rotation table 4 is sequentially moved among the processing stations A to F by index rotation of 60 degrees by the drive mechanism 3 of the index table 1. The first station A is a loading station, and the work rotation table 4
Place the work W on top. The second station B is a rough grinding station, and performs rough grinding using a grinding device 8a disposed above the index table 1. The third station C is a finish grinding station, and similarly performs finish grinding using 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. 5th station E
is a workpiece cleaning station, which 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 unloading the work W.

The grinding devices 8a to 8c respectively disposed above the second to fourth stations B to D have a grinding wheel shaft 10 equipped with a grinding wheel 9 suitable for each grinding process at the tip.
is rotated at a predetermined number of rotations by the drive motor 11, and the screw shaft 13 is rotated by each of the feed motors 12a to 12c with respect to the workpiece W on the workpiece rotation table 4, so that the grindstone shaft 10 is rotated at a predetermined rotation speed. It moves up and down in dimensions to perform surface grinding on the surface of the workpiece W to a predetermined dimension.

Further, the finish grinding station C and the fine finish grinding station D are respectively 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 B to D is controlled by a grinding control means 7 which receives signals from the gauge means 14 and 15, and the work W is sequentially ground to a predetermined machining dimension.

Work W by each of the above grinding stations B to D
In the grinding, as shown in Fig. 4, the rough grinding station B performs pre-grinding to process the workpiece W from the material dimension _H0 to the first dimension _H1 ,
The finishing grinding station C, which performs post-grinding, finishes grinding the workpiece W from the first dimension _H1 to the second dimension _H2 while measuring the machined dimensions with the gauge means 14. Furthermore, the precision finishing station D moves the workpiece W from the second dimension H ₂ to the third dimension.
Gauge means 1 up to H ₃ i.e. final product dimensions
In step 5, precision grinding is performed while measuring the machining dimensions. The gauge means 14 and 15 provided in the finishing and fine finishing grinding stations C and D are as follows:
First gauges 14a and 15a that measure the height of the workpiece mounting surface 4a of the workpiece rotary table 4 and the workpiece W
The second gauge 14b, 1 measures the height of the machined surface of
5b, and the machining dimensions of the workpiece W are measured from the difference between the two.

Each feed motor 1 of the grinding stations B to D
2a to 12c are attached with controllers 16a to 16c for controlling respective feed amounts, and measurement signals from the gauge means 14 or 15 are output to these controllers 16a to 16c. That is, the measurement signal of the gauge means 14 provided in the finish grinding station C is transmitted to the controller 16 of the feed motor 12b of this finish grinding station C.
B is output to rough grinding station B.
It is also output to the controller 16a of the feed motor 12a. The gauge means 14 of the finish grinding station C sequentially measures changes in the machining dimensions of the workpiece W during finish grinding, and when the machining dimensions reach a predetermined second dimension _H2 , the feed of the finish grinding This is to stop the feeding of the grindstone shaft 10 by the motor 12b. In addition, the gauge means 14 of the finish grinding station C measures the machining dimension _H1 of the workpiece W after rough grinding and before finish grinding,
The signal is outputted to the controller 16a of the rough grinding station B to correct and control the operating amount of the feed motor 12a with respect to the first dimension _H1 in machining the next 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 a predetermined finished dimension _H3 is reached. be. In addition, regarding the measurement by the gauge means 15 of this fine finishing station D, as described above,
The feed motor 12b of the finish grinding station C measures the machining dimension _H2 of the workpiece W after finish grinding.
Alternatively, the measurement signal may be outputted to the controller 16b of the finishing grinding station C to perform feedback control of the feed amount at the finishing grinding station C.

The above control basically involves comparing the measured dimension of the gauge means 14 with the currently set rough grinding dimension, that is, the first machining dimension _H1 , to find a dimensional difference;
When the measured machining dimension is larger than the set dimension, the set dimension is corrected in the negative direction, and when it is smaller, the set dimension is corrected in the positive direction.The currently set machining allowance is corrected by the above dimension difference. , no modification is necessary when they are equal.

Further, the rotating shaft 6 of the work rotating table 4
As shown in FIG. 2, a driven gear 17 is attached to the lower end portion 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. The driven gear 17 is attached to the output shaft of 18e.
A drive gear 19 is provided which can mesh with.

The rotation speed of the permanent motors 18a to 18e is controlled so as to obtain the required rotation speed of the work rotary table 4 during machining of the respective stations B to F, and the rotation speed of the permanent motors 18a to 18e is controlled by the drive mechanism 3 to rotate the index table 4. 1 is controlled to rotate at a low speed when indexing. During rough grinding at the second station B, finish grinding at the third station C, and fine finish grinding at the fourth station D, the rotation speed of the workpiece rotary table 4 during grinding is in the order of rough grinding, finish grinding, and fine finish grinding. controlled to decrease. 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 permanent motor 18
The capacity of motors d and 18e is smaller than that of the permanent motors 18a to 18c of the grinding station. Furthermore, when the index table 1 is indexed and rotated, if the permanent motors 18a to 18e are rotated slowly, the driven gear 17 of the work rotation table 4 is rotated as the index table 1 rotates.
are the permanent motors 18a to 18 of the station in the previous stage.
e, and can be smoothly engaged with the drive gears 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 cross-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 also by a support member 20 having an annular outer circumference, and this support member 20 is supported by a fixed leg 20a between each station A to F. fixed to a fixed part. In the drive mechanism 3, 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 facing the proximity switch 23 is attached to the upper end. 24 are 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 controlled by the gears 26, 2.
8 and worms 22 and 25 and is transmitted to the Geneva mechanism 21. When the shaft 21a rotates once, the index table 1 rotates 60 degrees, the cam body 24 operates the proximity switch 23, and the index motor 27 The index rotation of the index table 1 is completed by stopping the operation of the index table 1.

Further, the rotating shaft 6 of the work rotating table 4 passes through the support base 6, and a driven gear 17 is attached to the lower end thereof. The permanent motor 18a is attached to the support plate 34 on the fixed side, and is connected to the driven gear 17.
A drive gear 19 is provided which meshes with the drive gear 19. 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 introducing mechanism 35 is disposed below the rotating shaft 6, and a suction cup member 38 that moves up and down is attached to the rotating shaft 6.
The workpiece W is suctioned and held on the mounting surface 4a of the workpiece rotary table 4 by suctioning the lower end of the workpiece W and applying suction force thereto.

Note that the gauge means 14 and 15 may be non-contact gauges. Further, the number of processing stations in the above-mentioned embodiments is designed to be changed as appropriate depending on changes in the conditions of surface grinding, and the specific structure etc. are also changed.

[Brief explanation of the drawing]

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 the - line in FIG. 1 showing a grinding station,
Figure 3 is a schematic configuration diagram of the control system, Figure 4 is an explanatory diagram showing the grinding dimensions of a workpiece by each grinding station, and Figure 5 is a partial cross-section of 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, 8a to 8c...
... Grinding device, 9 ... Grinding wheel, 10 ... Grinding wheel shaft, 11
... Drive motor, 12a to 12c... Feed motor, 14, 15... Gauge means, 16a to 16c
...Controller, B~D...Grinding station.

Claims (1)

[Claims] 1. In a surface grinding machine that continuously performs pre-grinding at a pre-grinding station and post-grinding at a post-grinding station in separate stations so as to grind the surface of a workpiece to a predetermined size, the post-grinding station has a A gauge means is provided to measure the machined dimensions of the workpiece during post-grinding at the post-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. Grinding control means that compares the measured value with the set dimension determined as the machining allowance for the workpiece in the pre-grinding station to determine the dimensional difference, and corrects the machining allowance currently set in the pre-grinding station by the above-mentioned dimensional difference. A surface grinding machine control device characterized by being provided with.