JPS6165763A - Grinding device for end face of a plate - Google Patents

Abstract

PURPOSE:To have a constant grinding margin by making locational control of a grinding tool with a contour tracing means equipped with a single-joint horizontal revolving arm so that the application line of the grinding pressure is always oriented in the normal direction to the end face of the contour, and then performing the end-face grinding. CONSTITUTION:A glass sheet 1 is supported horizontally on a basis 3 with the aid of suction cups 2a, 2b, and a grinder unit 5 is locational controlled by a working robot 6 equipped with horizontal revolving arms 60, 62 of single joint type 61 on the basis of numerical control data prepared in correspondence to the contour data so that the grinding wheel 4 conducts tracing at a specified speed, and now the end face is ground. The grinding wheel 4 is also controlled by a servo motor on a third shaft theta3 so that the acting line of the grinding pressure applied to the end face of the glass sheet 1 is oriented in the normal direction to this end face, wherein the grinding pressure is given by a pneumatic cylinder 7.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to an end face polishing apparatus for plate glass.

[Conventional technology]

Group glasses of various shapes, such as rectangular, trapezoidal, and fan-shaped, are cut out from a large sheet of glass, and the end surfaces are polished (thread chamfering,
In the process of flat shaving, plate shaving, polishing, etc.
Conventionally, a worker applied a high-speed rotating polishing wheel to the end face of cut group glass to perform polishing. The group glass is suctioned and fixed on a rotary table and rotated at a constant low speed, while the polishing unit including the drive motor and polishing wheel is supported by a swing arm that can be horizontally rotated in the direction of the end surface of the glass. There is. The end surface polishing operation is performed by pushing a handle connected to the swing arm and pressing the polishing direction against the end surface of the glass plate that rotates at a low speed.

Therefore, in the conventional polishing process, manual work is involved, the polishing pressure is not constant, and if the rotational speed of the group glass is constant, the circumferential speed of the end face changes in accordance with the contour of the glass, so rJJFr' r: There was a problem that the speed was not constant and the polishing margin tended to vary.

Particularly complex parts such as automobile windshields ((Is it strange to chamfer the end face of irregularly shaped machine glass uniformly?)
Practicing work was required. In addition, the glass sometimes broke because the polishing wheel was suddenly pressed against the end surface of the glass at the polishing start point.

In order to save manpower, a device has been proposed in which the polishing unit is attached to a track frame extending in a radial direction from the center of the temporary glass to make it movable, and the polishing wheel is automatically polished while rotating around the outer circumference of the glass. There is (Jitsukai 58-1
No. 54044). However, this device manually adjusts the rotational speed of the polishing wheel relative to the glass end surface to obtain uniform polishing, so it does not completely eliminate the above-mentioned problems and requires manual intervention. Variations in the polishing margin due to this cannot be avoided.

Furthermore, a polishing device has been proposed that uses a polishing unit that can move along the X-Y axes of an orthogonal coordinate system and polishes the contour end face of temporary glass using numerical control data (Japanese Patent Application Laid-Open No. 59-1993). -37040). According to this polishing device, the polishing speed of the polishing wheel (contour tracing speed)
can be made constant regardless of the outer shape of the temporary glass, but it becomes a complex and large-scale device comparable to NO machine tools, and is expensive and occupies a large area.

[Problem that the invention seeks to solve]

--Kashu In view of the above-mentioned problems, it is an object of the present invention to provide a polishing apparatus that can automatically adjust the polishing speed with a simple configuration and thus provide a constant polishing margin.

[Means for solving problems]

The end polishing apparatus of the present invention is equipped with a contour tracing means for controlling the position of a polishing tool (polishing wheel 4 in the embodiment) along the contour of a plate-like object whose end surface is to be polished. This contour tracing means includes a single-joint horizontal rotation arm (60, 62).
The position of the polishing tool is controlled by numerically controlling a first axis (θ1) of the base end portion of the arm and a second axis (θ2) of the joint portion. Furthermore, a third axis (θ
3).

[For production]

With this configuration, it is possible to polish the end surface while controlling the speed of the polishing tool along the contour of the plate-shaped object, so a simple device can automatically polish a constant polishing margin without being affected by the contour of the end surface. It can be carried out.

〔Example〕

The present invention will be explained below based on examples.

FIG. 1 is a plan view of a polishing apparatus to which the present invention is applied, and FIGS. 2 and 3 are side views. In this embodiment, the temporary glass 1 whose end face is polished is used as a windshield of an automobile. This plate glass 1 has a pair of suction cups 2
It is horizontally supported by a base 3 having a and 2b, and end face polishing (chamfering, etc.) is performed by pressing a rotating polishing wheel 4 against the end face and tracing the outer periphery.

A polishing unit 5 consisting of a polishing wheel 4, its drive motor, etc. is moved along the outer contour of the glass plate 1 by a working robot 6 equipped with a single-joint horizontal rotation arm.

The external contour data is stored in advance in the robot/nod control section as numerical control (NC) data by circularly tracing the end face of the model shape. During the polishing operation, the position of the polishing unit 5 is controlled so that the polishing wheel 4 traces the end surface of the glass plate 1 at a set speed based on numerical control data corresponding to the external contour data.

The work robot 6 is a commonly available industrial robot,
It includes a first horizontal rotation arm 60, a joint 61 at its tip, and a second horizontal rotation arm 62 extending from this joint. The first rotation axis (first axis) θl at the base end of the horizontal rotation arm 60 and the base end (
The second axis of rotation (second axis) θ2 in the joint 61) is
A servo motor is incorporated in each arm, and the rotation angle of each arm is controlled by these servo motors.

A third rotation axis (third axis) θ3 in the vertical direction is provided at the tip of the second horizontal rotation arm 62, and controls the angle of the polishing unit 5 attached to the tip of the arm 62. The servo motor of the third member θ3 controls the direction of action of the polishing pressure that presses the polishing wheel 4 against the end face of the glass 1 so that it faces the normal direction of the end face. The polishing pressure is applied by biasing the spindle of the polishing wheel 4 toward the end surface of the glass sheet using a horizontally arranged pneumatic cylinder 7.

If the direction of action of the pneumatic cylinder 7 is the fourth axis, the polishing wheel 4 is given a degree of freedom in the fourth axis direction.
Even if there is a deviation between the locus of the polishing wheel 4 and the outer circumference of the temporary glass 1, this deviation is absorbed by the cylinder 7. Therefore, the positioning accuracy when fixing the temporary glass 1 with the suction cups 2a, 2b may be somewhat poor, and the playback (reproduction) performance of the robot 6 with respect to teaching data may be somewhat inferior. Also, the number of teaching points along the outer periphery of the glass plate may be relatively small.

In addition, the polishing pressure can be adjusted or controlled to be constant, and if necessary, the polishing pressure can be partially increased or decreased by adjusting the air pressure while tracing around the glass plate 1 to partially correct the polishing margin. It is also possible to do so.

4 and 5 are longitudinal sectional views of the polishing unit 5. FIG.

As described above, the polishing unit 5 is attached to the tip of the second horizontal rotating arm 62 via the third axis θ3. This third axis θ3 is driven by a servo motor SM3. A bearing 52 is provided in the housing 50 of the polishing unit 5.
are arranged vertically, and a spindle 51 is pivotally supported. The polishing wheel 4 is attached to the tip of the spindle 51, and the rear end is connected to the shaft of a drive motor 55 attached to the outside of the housing 50 via pulleys 53a, 53b and a belt 54.

The bearing 52 is installed in the housing 50 so as to be slidable in the horizontal direction via a slide guide 56, and is attached to the pneumatic cylinder 7.
It can be displaced in the horizontal direction by expanding and contracting the piston rod 7a. A coil spring or the like may be used instead of the cylinder 7. Note that depending on the displacement of the bearing 52, the belt 54
Since it is necessary to expand and contract the belt 54, a tensioner 57 is provided to press the side surface of the belt 54, and as the bearing 52 is displaced, the tensioner 57 absorbs the variation in the length of the belt 54. ing.

A cooling water spray nozzle 8 is provided on the side surface of the housing 50, and is configured to spray polishing liquid onto the polished portion. Further, a support arm 9 is extended from the side surface of the housing 5o around the lower side of the polishing wheel 4 to the vicinity of the polishing section, and the tip thereof is provided with a roller l that contacts the lower surface of the plate glass 1.
O is attached. This roller 10 prevents the periphery of the glass from being bent, which is caused by the polishing wheel 4 being pressed against the end surface of the temporary glass 1 during the polishing operation.

Next, FIG. 6 is a plan view showing a modification of the polishing apparatus of the present invention, and FIG. 7 is a side view. In this example, a single-jointed support arm 11 is also used to support the weight of the polishing unit 5. This support arm 11 holds the plate glass 1 with a suction cup 2.
The horizontal rotating arm 11a is rotatably supported on a base 3 supported by points a and 2b, a joint 11b at its tip, and a horizontal rotating arm IC extending from this joint. A polishing unit 5 is supported at the tip of the horizontal rotation arm llc,
Further, a part of the polishing unit throat 5 is connected to the tip of a horizontal rotating arm 62 of the working robot 6 via an L-shaped member 12. A spindle 51 on which the polishing wheel 4 is mounted projects in this example onto the top of the polishing unit 5 which is supported by a support arm 11 .

The working robot 6 is similar to the embodiments shown in FIGS. 1 to 5,
The polishing wheel 4 is moved along the outer periphery of the glass plate l based on the stored contour data.

On the other hand, the support arm 11 deforms freely following the movement of the robot arm while supporting the weight of the polishing unit 5. The third axis θ3 is controlled by a servo motor SM3 whose axis coincides with the spindle 51 of the polishing unit 5.

This servo motor SM3 is attached to the tip of one horizontal rotating arm 62 of the work robot 6, and controls the direction of action of the pneumatic cylinder 7 that applies polishing pressure via the L-shaped member 12.

In addition, in order to hold the polishing unit 5 rotatably about the third axis θ3, the tip of the support arm 11 and the polishing unit 5
A thrust bearing 13 is interposed between the third shaft and the third shaft.

In addition, in FIGS. 6 and 7, a fixed drive motor is provided in the base 3, and rotational driving force is transmitted to the spindle 51 of the polishing unit 5 via a belt inserted into the hollow support arm 11. The polishing wheel 4 may also be rotated. According to this configuration, the weight of the polishing unit 5 can be reduced.

Next, FIG. 8 is a plan view of the main part of the polished portion showing another method of applying polishing pressure. In this example, a third horizontal rotation arm 63 is further attached to the third axis θ3 at the tip of the horizontal rotation arm 62 of the work robot 6, and a polishing unit 5 is attached to the tip of the third axis θ3.
is installed.

First and second horizontal rotation arms 61°62 of the robot 6
Based on preset trace data, the polishing wheel 4 is moved along the outer contour of the glass plate 1 while keeping the third horizontal rotating arm 63 parallel to the tangent to the temporary glass 1.

Although the third horizontal rotating arm 63 is not directly used for positioning the polishing wheel 4, the rotational torque for pressing the polishing wheel 4 toward the end surface of the glass plate l is generated along the third axis θ.
3 by a rotary actuator RA. Further, in order to keep the polishing pressure constant, a torque limiter is interposed between the rotary actuator RA and the third axis θ3. Note that the rotary actuator RA may be one that converts the telescopic movement of a piston rod of a pneumatic cylinder into a rotational movement using a rack and a pinion, for example. Furthermore, a winding spring or the like may be used in place of the rotary actuator.

In the above embodiments and modifications (FIGS. 1 and 6), the temporary glass 1 is fixed by the suction m2 a'2b of the base 3, and the arms 60 and 62 of the working robot 6 are fixed.
Accordingly, the polishing unit 5 traces the outer contour of the temporary glass 1. In this case, the working range of the robot 6 is
For example, it covers the shaded area in FIG. If the temporary glass 1 is so large that it deviates from this working range, or if the working range of the robot 7) becomes smaller due to various conditions, the base 3 can be used as a rotating table to move the temporary glass 1 in 90° or 180° increments, for example. Alternatively, the polishing work may be divided and performed at each rotation stop position. Alternatively, the base 3 may be made slidable relative to the robot 6, and the polishing work may be performed at each sliding position. Furthermore, these rotation and sliding movements may be combined. Further, the polishing work may be performed while rotating the base 3 at a constant speed. It is also conceivable to have a plurality of working robots and have each robot work on each polishing side of one piece of temporary glass 1.

Next, FIG. 9 is a block diagram of the control section of the working robot used in the polishing apparatus according to the present invention. As shown in FIG. 9, the control unit includes a first CPU 15 and a second CPU 16, the first cPU 15 mainly performs NC interpolation calculations and servo control of the motor of each axis, and the second CPU
16 performs NC data management and system control. Control data and a control program for polishing the end surface of a glass plate are input from an external storage device 17 such as a floppy disk device into the memory of the second CPU 16 via an interface 18 . 1st CPU
15 performs linear interpolation or circular interpolation based on the data from the CPU 6 to create NC data, and then outputs the data from the 3rd machining axis to the 3rd axis (θ1 to θ) via the NC control interface 19.
3) to the servo units 20 to 22. Servo units 20 to 22 are servo motors SMI to SM3 for each axis.
Derive the control current output.

Each servo motor SMI~SM like general NC, equipment
A tachometer generator TG and a pulse generator PG are attached to each of the motors 3 and 3. The output of the tachogenerator TG is fed back to each servo unit, and the output from the motor SMI~
Control is performed so that SM3 reaches the instructed rotational speed. In addition, the output of the pulse generator PG generated for each unit rotation angle of each motor SMI to SM3 is sent to CPtJ1 as position information via the NC control interface 19.
5, and calculation control is performed so that each position of the three axes matches the NC data.

System operation, management, modification of data and programs, etc. are conducted via the interface 18 to the second CPU 6.
This is carried out using a keyboard 24 and a CRT 25 that are combined with a keyboard 24 and a CRT 25. Further, control signals are given to various control external relay units 26 of the research PA device through the interface I8. Furthermore, as described above, when changing the polishing pressure by adjusting the air pressure of the pneumatic cylinder 7 in the polishing unit 5, the first CPU 15 uses the polishing pressure data set in advance along the outer periphery of the temporary glass 1. A control signal is given to the pneumatic cylinder controller 23 through the interface 19, and a pneumatic control section, which will be described later, is operated based on the output of this controller.

As described above, when rotating or sliding the plate glass 1 for the purpose of effectively using the working area of the working robot 6, the interface 19 connects the motors LM with the rotational axis θ and the linear movement axis θ, A motion command is given to the In this case as well, each motor is configured to be servo-controlled if necessary.

FIG. 10 is a detailed plan view showing an example of the temporary glass 1 whose end face is polished, and FIG. 11 is a flowchart showing the operation of the teaching box 24. Data representing the external contour of the temporary glass 1 can be obtained by determining the movement trajectory of the polishing wheel 4 by operating the teaching box 24 connected to the interface 18 shown in FIG. are sampled. Since interpolation (primary or secondary) is performed during NC control, sampling intervals are sparse in parts of the glass outer shape where the curvature is small, and sampling intervals are dense in parts with large curvature.

As shown in FIG. 11, the teaching box 24 has a first
- It has forward/reverse command keys for the third axes θl to θ3, and operation commands by operating these keys are processed by the CPU 15.1.6, and are sent to the servo units 20 to 2 through the interface 19.
2 to the servo motors SMI to SM3 of each axis. This positions the polishing wheel 4 at each sampling point and orients the line of action of the pneumatic cylinder 7 in the normal direction.

For polishing speed, press SPD↑ (speed amplifier) key or SP
By pressing the D↓ (speed down) key, the speed can be set for each sampling point in 16 steps, for example. If necessary, increase the polishing pressure by pressing the oos↑ (pressure increase) key or P.
For example, the pressure can be specified in eight steps using the H11 (pressure decrease) key.

Adjustment of the polishing pressure is performed when the polishing margin cannot be made constant by controlling the polishing speed alone. For example, in the X section (/J) R section in Figure 10, where the curvature is extremely large, there is too much scraping, so the polishing pressure must be reduced, and the Y section (reverse R section) where the curvature is negative.
Since the cutting margin is too small, the polishing pressure is increased.

The teaching data at each sampling point P is
These are stored in the external storage device 17 as the count value of the pulse generator output of each axis and the setting values of the polishing speed and polishing pressure. For memory commands, press the REC (record) key or ALT (change)
given by the key.

The ALT key is used to change the past data of this sampling point when modifying the movement trajectory of the polishing wheel 4. When the teaching of one sampling point P, is completed, P,. Press the 1 key to advance to the next point. Also, if you press the Pi-1 key, you can return to the previous sampling point, so you can check the trace status.

In addition to the contour trace data of the glass plate 1, the arrogant path and speed for moving the polishing wheel 4 from its reset (standby a) position to the polishing start position of the end surface of the glass can also be set using the teaching box 24.

Therefore, by lowering the speed at which the polishing wheel 4 hits the end surface of the glass, it is possible to prevent the glass from chipping due to a sudden start of polishing.

FIG. 12 is a flowchart showing an outline of NC control. First, an NC operation command is generated from the CPU 16, and three-axis NC control is started. Since the absolute coordinate data of each sampling point is given through teaching, the relative coordinates of the next polishing unit are first calculated from the absolute coordinates of each axis and the current coordinates. Relative coordinate data is then given to the NC control interface 19 for each axis. Also, the frequency of the basic pulse generator of the NC control interface 19 is set based on the speed data. This determines the trajectory and speed of the NC to the next point, so next
An operation command is simultaneously given to the NC control interface 19 of the axis, and NC control of the polishing unit 5 is performed by linear or circular interpolation. When one step of operation is completed, a termination pulse is sent from the interface 19 to the CPU 16.
, the position pointer is incremented by one, and the CPU 16
Under the control of , operations such as reading control data and calculating coordinates for the next point are executed again. When all steps are completed through this repetition, the end face polishing work for one glass plate is completed.

FIG. 13 is a block diagram showing an example of a pneumatic control section for adjusting polishing pressure. An electrical-to-electrical converter 27 is used as the air pressure adjusting means. This converter includes a solenoid and a pressure regulating valve, and provides a pneumatic output proportional to the input current. For example, 1mA, 2m as a current input source
A, 4 mA constant current sources 28a, 28b, 28c are prepared, and the combination of their outputs is connected to the relay RYI~
Eight levels of current can be obtained by selecting with RY3.

Control signals for these relays RYI to RY3 are sent to the pneumatic cylinder controller 2 in Fig. 9 based on teaching data.
It is given in 3 to 3 bits. The combined control input current is applied to the current input terminal of the electrical-to-electrical converter 27, and the corresponding pneumatic output is supplied to the pneumatic cylinder 7 via the shutoff valve 29 to apply the required polishing pressure. .

Note that the output of the pneumatic cylinder controller 23 in FIG.
After converting to an analog value with a /A converter, the sky in Figure 13 -
It may also be applied to the electric converter 27.

FIG. 14 is a block diagram showing another embodiment of the pneumatic control section. In this example, the pneumatic pressure adjusted to Pl, P2, and P3 by the pressure regulating valves 302 to 30c is controlled by the solenoid valve 31.
They are combined (selectively added) by opening and closing of a to 31C, and are outputted to the pneumatic cylinder 7 as an adjusted pneumatic output. Each electromagnetic valve 31a-31b is operated by a 3-bit pneumatic control signal as in FIG.

In order to obtain a constant polishing margin, in addition to controlling the polishing speed and polishing pressure described above, the drive motor 55 of the polishing wheel 4 is
The polishing margin may be corrected by partially controlling the rotational speed of the polishing wheel 4 while the polishing wheel 4 rotates around the peripheral end surface of the plate glass 1 using preset data.

〔Effect of the invention〕

As described above, the present invention provides the following features: - The polishing tool is position-controlled by the contour tracing means provided with the horizontally rotating arm of the joint to perform end surface polishing, and the line of action of the polishing pressure always follows the normal direction of the contour end surface. Since it is oriented in the same direction, automatic polishing can be performed using a simple device, and by including the contour tracing speed in the position control information, it is not affected by the external shape of the plate to be polished (large or small curvature, concave curve, convex curve, etc.) A certain amount of polishing margin can be obtained without polishing.

[Brief explanation of drawings]

FIG. 1 is a plan view of a polishing device to which the present invention is applied, FIGS. 2 and 3 are side views, FIGS. 4 and 5 are vertical sectional views showing details of the polishing unit, and FIG. 6 is a polishing device. 7 is a side view of FIG. 6, FIG. 8 is a partial plan view of a modification of the pressure means that applies polishing pressure, and FIG. 9 is a diagram of the control unit of the working robot. 10 is a detailed plan view showing an example of temporary glass whose end face is polished, FIG. 11 is a flow chart showing the operation of the teaching box in FIG. 10, FIG. 12 is a flow chart of NC control, and FIG. FIG. 14 is a block diagram showing an example of a pneumatic control section for adjusting the polishing pressure. FIG. 14 is a block diagram showing another embodiment of pneumatic control. In addition, in the symbols used in the drawings, 1----1・---11----plate glass 2a,
2b-・・・-・−−−−One sucker 3・−−−−−・・−
...−・−・−Base 4−・−−−1−・−・・−・−
- Polishing wheel 5 - - - - - - - - - - - - - - - - Polishing unit 6 - - - - - - - - - - - Working robot 7 - - - - - - -・−・・−Pneumatic cylinder 27
-・・−・−・−−1−−・−Electric pneumatic converter 30a to 3
9c - Pressure regulating valve 60 - - - - - - - - m - Horizontal rotating arm 61 - - - - - - - Joint 62 - -
・−・−Horizontal rotating arm θ1−−−−−−・−1−−−−・First axis θ2・−・−1−−−・−・−Second axis θ3−・−− -1------------This is the third axis.

Claims (1)

[Claims] The contour tracing means is equipped with a contour tracing means for controlling the position of a polishing tool along the contour of a plate-like object whose end surface is to be polished, and the contour tracing means is equipped with a single-jointed horizontal rotation arm, and the first axis of the proximal end portion of the arm is The position of the polishing tool is controlled by numerical control of the second axis of the joint part, and a polishing pressure is applied to the tip of the horizontal rotating arm to press the polishing tool in a direction substantially normal to the end surface of the plate-shaped body. An end face polishing device for a plate-shaped body, characterized by comprising a third axis for action.