DE3546491A1 - Plate-glass grinding machine - Google Patents

Abstract

A plate-glass grinding machine (1) with numerical control has a number of stands (9), grinding heads (5), which are arranged opposite the stands (9), means for effecting a rectilinear movement of the grinding heads (5) in two perpendicular directions with respect to each other, and control means for the numerical control of the linear movement, in order to move the grinding wheels (7) of the grinding heads (5) along the peripheral edges of glass plates (8), which are held on the stands (9), and in order to grind the peripheral edges of the glass plates (8) by the grinding wheels (7). Each of the grinding heads (5) is attached on the means for effecting the linear movement in such a way that the grinding head (5) can turn about an axis which extends through a grinding point on the grinding wheel (7) and runs perpendicularly with respect to the plane of the glass plate (8). Each grinding head (5) can, furthermore, be moved parallel to a straight line which connects the grinding point to the centre of rotation of each grinding wheel (7). <IMAGE>

Description

The invention relates to a glass plate grinding machine according to the preamble of claim 1.

Known numerically controlled glass plate grinding machines have difficulty adjusting the position of the Grinding wheel with ground grinding wheel, because this is usually rigidly mounted.

The object of the invention is a numerically controlled Glass plate grinder regarding the positioning improve the accuracy of the glass plate to be ground.  

The characteristic note serves to solve this task male of claim 1.

Hence the task is created by creating a Glass plate grinding machine with numerical control solved, which comprises the following components: a number of stands; grinding heads attached to the stands; Means of induction a linear movement of the grinding heads relative to the Stands in two directions perpendicular to each other; and Control means for numerically controlling the linear movement in the way that the grinding wheels along the grinding heads the peripheral edges of the glass plates that are moved to the Stands are held and the peripheral edges of the Glass plates are ground from the grinding wheels, each of the grinding heads on the means for effecting the linear movement is held so that everyone Grinding head can rotate about an axis, which is by a Grinding point on the grinding wheel of the grinding head to the Glass plate runs and so on the means of effect the linear movement are suspended that the grinding head can move in the direction parallel to a straight line, which the grinding point with the turning center for the grinding disc of the grinding head connects; and further by means for rotating the grinding head around the axis and by means for moving the grinding head individually and independently in Direction parallel to the straight line; and being the Control means are designed so that they are numerical Exercise control on the means for turning so that the Normal is aligned to the grinding point with the straight line.  

The invention is illustrated below with the aid of an embodiment explained in more detail; show it:

Fig. 1 is a front view of a grinding machine;

Fig. 2 is a plan view of the grinding machine;

Fig. 3 is a side view of the grinding machine;

Fig. 4 is an enlarged side view of part of the grinding machine;

Fig. 5 is an enlarged front view of part of the grinding machine;

Fig. 6 is an enlarged plan view of a part of the grinding machine; and

Fig. 7 is an electrical and pneumatic circuit diagram of a fluid actuator.

In Figs. 1, 2 and 3, the device of the invention in form of a grinding machine main body 1 to grind the peripheral edges of glass plates at nume driven-controlled movement of the grinding wheel 7 is shown and it is also a feed device 2 for feeding the glass plates to the Schleifmaschinen- Main body 1 and an output device 3 for outputting the cut glass plates are shown, which are each mounted on a machine bed 4 .

The grinding machine main body 1 is suitable for grinding the peripheral edges of glass plates 8 by moving each grinding head 5 in the direction of an axis X in FIG. 2 from left to right and vice versa and in which a table 6 is moved back and forth in the direction of an axis Y. can, at the same time each of the grinding wheels 7 is moved along the peripheral edge of the glass plate 8 , while each grinding wheel 7 is rotated about an axis which is arranged perpendicular to the plane of the glass plate 8 and passes through the grinding point A of the grinding wheel 7 .

The mounted on the machine bed 4 table 6 can move in the Y direction and carries stands 9 , five of which are arranged in a row to hold the glass plates 8 to be ground. These stands 9 can hold the glass plates 8 by means of a vacuum clamping device. For this purpose, each of the stands 9 is connected to a vacuum pump (not shown) via pipes and valves. The table 6 has sliding elements 10 in the middle and at its two ends, which run parallel to one another in the direction Y , and lies on sliding rails 11 , in which the sliding elements 10 engage. Since these slide rails 11 are arranged parallel to one another in the Y direction on the machine bed 4 , the table 6 can be moved on the machine bed 4 in the Y direction.

A servomechanism for the movement in the direction Y has three groups of set screws 12 which are arranged along the sliding elements 10 , gear 13 and a shaft 14 connected to the set screws 12 and a Y- axis servo motor 16 which drives the shaft 14 via a Belt 15 drives. Each of the set screws 12 has ball screw threads 17 and a nut 18 , and each ball screw 17 is fastened to the machine bed 4 via a bearing 19 , while the nut 18 is fastened under the table 6 . The ball screws 17 are connected to the gears 13 on the machine bed 4 and the gears 13 are in turn connected to one another by the shaft 14 . The shaft 14 is supported at various points on the machine bed 4 by bearings 20 . The belt drives 15 expediently comprise a V-belt and pulleys.

A support structure 22 is held by supports 21 above the table 6 , which are net angeord on both sides of the machine bed 4 . Two groups of slide rails 23 are net angeord parallel to the axis X on the front of the support structure 22 . The slide rails 23 have a rail body 24 , which lies on the support frame 22 , and a number of slide elements 25 , which move on the rail body 24 , and furthermore, an engine block 26 is fastened to the slide elements 25 . Accordingly, the engine block 26 can be moved in the X direction by the slide rails 23 .

The acting in the X direction servomechanism has set screws 27 , which are arranged between the two groups of slide rails NEN 23 , and an X- axis servo motor 28 , which is usually by a belt or the like. is coupled to the set screws 28 . The set screw 27 has a ball screw 29 and a nut 30 , the ball screw 29 being fastened to the support frame 22 by a bearing 78 and the nut 30 to the engine block 26 .

The engine block 26 shown in FIG. 4 is equipped with five grinding heads 31 in such a way that they are arranged above the respective stands 9 on the table 6 and that each of the grinding heads 31 has a mounting device 32 , a grinding head 5 hanging on the mounting device 32 and one with the mounting device 32 connected Drehan drive 33 has. Each of the grinding heads 31 is fastened to the engine block 26 via the mounting device.

Referring to FIGS. 4 to 6 5, the grinding head comprises a spindle motor 34 and a Verschiebungseinstellvorrichtung with a cutting direction Einstellführung 42, a Querfüh tion 43 and a vertical guide 79, to the erecting 34 position of the spindle motor in the vertical direction and into two in the horizontal plane to set directions perpendicular to each other. The grinding wheel 7 is attached to the shaft of the spindle motor 34 . The holding device 32 has a rotating shaft 36 , a number of bearings (not shown) for supporting the shaft 36 and a housing 37 for holding the bearings. The bracket 32 is through the housing 37 on the engine block 26 is introduced . The entire grinding head 5 is suspended to hold the displacement adjuster on the lower part of the rotating shaft 36 and a bevel gear 38 is arranged on the upper part of the rotating shaft 36 to form the rotary drive 33 . The grinding head 5 is rotatable about the rotating shaft 36 of the holding device 32 as an axis of rotation.

In Figs. 1 and 2 of the servo mechanism for transmitting the rotational movement has the rotary drive 33 composed of the bevel gear 38 at the upper end of the rotating shaft 36 of the mounting device 32, the rotary drive 33 connecting with the respective grinding head device drive shaft 39 and with the Drive shaft 39 connected servo motor 40 for turning on. The drive shaft 39 is driven by the rotating servo motor 40 , whereby the grinding head 5 and thus the grinding wheel in each grinding head device 31 are simultaneously rotated by the respective rotary drive.

If the center of rotation is set for the grinding wheel 7 so that it coincides in FIG. 4 with the grinding point A of the grinding wheel 7 with respect to the glass plate 8, by the Verschiebungseinstellvorrichtung of each grinding head 5, the grinding wheel 7 feeds due to a numerical control by a rotary movement and moves along the peripheral edge of the glass plate 8 , which is held on each of the stands 9 , according to the numerically controlled movement of the table 6 and the engine block 26 and thereby grinds so that the grinding point A always on is held in a constant position.

In the following, an explanation is given for the principle according to which the grinding wheel 7 carries out the grinding while a rotary movement according to numerical control is being carried out, and the advantages achieved are explained with reference to FIGS. 4 to 6.

The grinding wheel 7 is held during the movement along the circumferential edge of the glass plate 8 in such a way that the grinding head 5 carries out a rotary movement about an axis which occurs through the grinding point A of the grinding wheel 7 and perpendicular to the plane of the glass plate 8 . The angle of rotation of the grinding wheel 7 lies under the numerical control such that the normal line on the profile of the peripheral edge of the glass plate 8 is aligned with a straight line connecting the grinding point A with the center of rotation 41 of the grinding wheel 7 . In such a structure of the grinding wheel 7, the holding position can be set for the grinding wheel 7 characterized in due completion of abrasion diameter reduction may be that the grinding wheel is single moved 7 Lich in one direction, through the cutting direction Einstellführung 42 such that the Grinding point A is aligned with the axis of rotation 36 of the grinding wheel 7 . This means a major advantage for the Glasplat ten grinding machine, if a number of glass plates 8 is ground simultaneously by a number of grinding wheels 7 . Namely, since the abrasion of the grinding wheel 7 can be predetermined, of the grinding point A for the grinding wheel 7 can be easily compared to the center of rotation 36 of the grinding wheel 7 by simply moving the cutting direction Einstellführungen be aligned to the respectively desired degree 42nd The movement of each cutting direction adjustment guide 42 is conveniently controlled by a shift servo motor 44 according to the numerical control of FIG. 6.

The control mechanism for the grinding contact pressure is explained below with reference to FIGS. 4 to 6.

In Figs. 4 to 6 the same parts as in Figures 1 carry. To 3 same reference numerals.

In these figures, the displacement adjustment device 35 has a cutting direction adjustment guide 42 , a transverse guide 43 and a vertical guide 79 . A shift control device 45 connected to a spindle motor 34 and a fluid actuator 46 is attached to the cutting direction setting guide 42 . The displacement control device 45 is mounted such that its direction of movement is parallel to the direction of movement of the cutting direction setting guide 42 . The Fluidbetä tiger 46 can move the spindle motor 34 and thus the grinding wheel 7 back and forth in the direction of movement of the displacement control device 45 and thus change the contact pressure of the grinding wheel 7 on the glass plate 8 . A ball guide bearing is suitably used for the shift control device 45 so that the Fluidbetä tiger 46 can be moved with little operating force. Furthermore, an air cylinder is advantageously used as a fluid actuator 46 .

For the control of the actuating force for the fluid actuator 46 , a primary air pressure is supplied to an electropneumatic converter 47, and a secondary air pressure controlled by the electropneumatic converter 47 is transmitted to the fluid actuator 46 to control the pressing force for the fluid actuator shown in FIG. 7. The electropneumatic converter 47 is designed so that the pneumatic pressure output is changed in relation to the electrical current fed.

On the other hand, the current signal input to the electropneumatic converter 47 is generated by a current converter 48 . The current transformer 48 is coupled to an auxiliary function part of a numerical control device 49 which controls the grinder main body 1 and which is designed to generate a number of current pulses while receiving a number of auxiliary function signals from the numerical control device 49 . The current converter 48 is usually constructed as a variable resistor or as a digital / analog converter system. Furthermore, the electropneumatic converter 47 can be connected to a separate control device, to a setting instrument or to a functional amplifier, so that it does not have to be operated in connection with the numerical control device 49 .

While an air cylinder is commonly used as the fluid actuator 46 , the secondary air pressure generated by the electropneumatic converter 47 can be connected to a hydraulic pressure converter and converted into a fluid pressure corresponding to the secondary air pressure, and the hydraulic pressure can be supplied to the fluid actuator 46 .

In this way, the electropneumatic transducer 47 changes the secondary air pressure supplied to the fluid actuator 46 by the signal from the numerical control device 49 in such a way that the grinding wheel 7 grinds in a controlled manner with respect to its contact pressure on the glass plate 8 . The contact pressure is expediently so that the grinding wheel 7 presses more strongly against the circumference of the glass plate 8 in the straight part of the glass plate and less strongly at the corners. At a corner where the radius of curvature is extremely small, the feed rate of the grinding wheel 7 is usually reduced compared to the glass plate 8 and at the same time the above-mentioned secondary air pressure is reduced. The grinding can therefore be uniform since the contact pressure can be reduced at points where the grinding wheel 7 on the glass plate 8 is grinding too much material.

The change in the secondary air pressure ranges from 0.3 bar to 1.5 bar for a fluid actuator 46 with a 40 mm diameter.

In Figs. 1 to 3, the delivery device 2 in respective blocks is divided 50 A to 50 E according to the respective stator 9 of the grinding machine main body 1 and each of the blocks 50 A - 50 E is provided with a feed device 51 for feeding the glass plates 8 and provided with a position detector 52 to stop the glass plate fed from the feeder 51 at the position corresponding to a stand 9 . Furthermore, the device 2 Zuführeinrich a lifting device 53 for lifting the Zuführeinrich tung 51 on each of the blocks 50 A - 50 E on.

The feed device 51 has a roller conveyor 54 for pushing the glass plates 8 and a belt conveyor 55 for moving the glass plates 8 . The roller conveyor 54 has a frame part 56 and each of the roller groups 57 , which are arranged on the frame part 56 , in which the frame part 56 is held on the machine bed 4 via a shaft 58 . The roller conveyor 54 is pivotable about the shaft 58 as a center line perpendicular to the support 9 . Furthermore, the belt conveyor 55 is attached to the frame part 56 and has a plate 59 , a pulley 60 , a belt 61 and a drive 62 . The frame member 56 is shown in FIG. Tipped 3, when the feeder 51, the glass plate 8 feeds, the latter being on the roller conveyor 54 due to the frictional force in cooperation with the movement of a belt 61 slides, the frictional force by the abutment of the peripheral edge of the glass plate 8 at the Volume 61 is caused.

Under each feed device 51 , the associated Hubein device 53 is arranged as a first lifting device, which controls each frame part 56 of the feed device 51 in a raised position in which the frame is inclined relative to the horizontal plane, expediently at an angle of 38 ° when feeding the glass plate 8 , and also controls each frame part 56 of the feed device 51 into a lowered position, in which the frame is lowered substantially horizontally when the glass plate 8 is transferred from the feed device 51 to the stand 9 .

In this way, the glass plates 8 , which are cut to a desired shape in a preliminary stage for the grinding work, are successively fed from a receiving conveyor 81 to the feed device 51 of the feed device 2 . In this case, the belt conveyor 55 is operated for each of the blocks 50 A - 50 E by a respective drive device 61 and the first glass plate 8 is conveyed to the outermost end block 50 A. Then, when the correct position detector 52 which is attached to the frame part 56 of the block 50 A, the arrival of the glass plate 8 determines 50 A at block, then the belt conveyor 55 is stopped of the block 50 A and the frame member 56 is caused in the raised Waiting position. In the same way, glass plates 8 are fed from the blocks 50 B to 50 E and stopped one after the other. In this case, the table moved in the Y direction toward the feeder 51 waits under each of the feeders 51 . The respective feed devices 51 , which are held in the raised position, are simultaneously lowered by the lifting devices 53 , as a result of which the respective glass plates 8 are simultaneously placed on the respective stands 9 and held there by negative pressure. Then the table 6 receiving the glass plate 8 is moved by 1 for the purpose of grinding against the grinding machine main body.

The dispensing device 3 has a belt conveyor 63 as a moving device for receiving the glass plate 8 from each of the stands 9 and moves the plate in the direction of the Y axis, and it also has a lifting device 64 as a second lifting device for raising the belt conveyor 63 , a roller conveyor 65 as a transfer device for transferring the glass plate and a drive device 66 for driving the roller conveyor 65 .

The belt of the belt conveyor 63 is guided around pulleys 69 and 70 , which are arranged on a support frame 68 of the lifting device 64 , the pulley 70 being connected to a drive device 71 and being driven by it via a suitable transmission device. The support frame 68 of the lifting device 64 is supported by a shaft 72 on the machine bed 4 and swivels vertically with respect to the stand 9 around the shaft 72 as the center, specifically by a drive device 73 . The roller conveyor 65 has a frame part 74 and a group of rollers 75 which are arranged on the frame part 74 and each of the rollers is connected to and driven by the drive device 66 via a chain drive.

In this way, the table 6 carrying thereon by the grinding main body te 1 finish-ground Glasplat 8 is moved in the direction Y to the output device 3 and waiting at the transfer position B of FIG. 3. At the time there is the supporting frame 8 of the Hubein direction 64 in a substantially horizontal, lowered position. At the same time that each of the stands 9 interrupts the suction of the glass plates 8 , the support frame 68 of the lifting device 64 rises and the glass plate 8 is transferred to the belt conveyor 63 . Further, the belt conveyor 63, which carries thereon the glass plate 8 is moved by the drive means 71 in the direction of Y, and when the glass sheet arrives 8 according to the discharge position C. Fig. 3, the support frame is lowered 68 of the lifting device 64 to the glass plate 8 to transfer to the roller conveyor 65 . Then the glass plate 8 is transferred by the roller conveyor 65 to an output conveyor 67 . The table 6 , which has transferred the glass plate 8 to the dispensing device 3 , is immediately reversed and moved in the direction of the feeding device 2 and repeats the work sequence described above.

With the numerically controlled grinding machine, the previously Excessive depth of cut may have been described Grinding of the glass plate can be prevented, even by yourself then when the feed speed of the grinding wheel is on a corner or similar decreases at which the radius of curvature is extreme is small, and the position of the grinding wheel can be adjust slightly when the grinding wheel is ground is.

Claims (4)

1. Glass plate grinding machine with numerical control, characterized in that a feed device ( 2 ) for the glass plate ( 8 ) is arranged on one side of the row of stands ( 9 ) on the grinding machine and that the feed device ( 2 ) is a feed device for feeding which has glass plates ( 8 ) and position detectors ( 52 ) for determining the arrival of a glass plate ( 8 ) at a position corresponding to a stand ( 9 ) and a first lifting device ( 53 ) for lifting the feed device ( 51 ) in such a way that the glass plate ( 8 ) is transmitted to the stand ( 9 ) when the feed device ( 51 ) is lowered. 2. Grinding machine according to claim 1, characterized in that an output device ( 3 ) for glass plates ( 8 ) on the other side of the row of stands ( 9 ) of the grinding machine ( 1 ) is arranged and that the output device ( 3 ) means for Moving a glass plate ( 8 ) received by the stand ( 9 ) to the dispensing device ( 3 ) and a second lifting device ( 64 ) for lifting the transport device in such a way that the glass plate ( 8 ) is taken over by the stand ( 9 ) when raises the conveyor. 3. Grinding machine according to claim 1 or 2, characterized in that the same number of feed devices ( 51 ) as stands ( 9 ) are arranged on the grinding machine ( 1 ). 4. Grinding machine according to one of claims 1 to 3, characterized in that each of the feed devices ( 51 ) has a roller conveyor ( 54 ) for pushing the glass plate ( 8 ) and a belt conveyor ( 55 ) for moving the glass plate ( 8 ).