Patent Application
20240228358
The present invention relates to an installation for producing at least one useful part from a glass pane by means of processing steps, which comprise cutting, breaking and grinding.
Such an installation is known, for example, from patent application EP 1 647 534 A1 by the same applicant. The constant optimization and monitoring of the installation, for example with regard to the best possible product quality (e.g. glass dimensions, ground profile shape and surface), long tool life (e.g. grinding wheels), short cycle times or reduced energy consumption is almost exclusively the responsibility of the operating personnel. Due to the great complexity of the technical relationships and interactions, the potential of the installation cannot be fully exploited by the operating personnel. The quality of the glass as the final product can be determined during ongoing production only after it has gone through the process chain by means of “human” assessment and measurement. Conclusions about the causes of observed faults are only possible with a lot of experience or not possible at all.
US 2006/0232403 A1 discloses an installation for producing a glass ribbon from a glass melt, which glass ribbon is continuously divided into glass panes by means of scoring and breaking. Sensors are used to detect sound during the scoring and breaking process. The respective glass pane represents a primitive, which must be further processed by means of dividing and grinding in order to obtain an end product with the desired quality. Nothing is disclosed in this US application regarding these further processing steps.
Proceeding from this, it is an object of the present invention to specify an installation for producing at least one useful part from a glass pane having improved operation and a method therefor.
This object is achieved by an installation according to claim 1 and a method according to the independent method claim. Preferred embodiments of the installation and the method are specified in the further claims.
By detecting a first measured variable, which can be detected during the execution of one of the processing steps, and by including at least one further measured variable, the control device can influence the ongoing processing, a subsequent processing step and/or the processing of a subsequent glass pane and/or useful part by means of a corresponding evaluation. A processing step is a working step, i.e. a step in which the glass pane or the useful part is worked. Working includes cutting, breaking and grinding and optionally one or more further working steps such as drilling. Other measured variables can be detected, for example, during the execution of the same or another processing step in which the first measured variable can be detected, and/or specify at least one process parameter for a processing step and/or can be detected outside a processing step, i.e., before and/or after a processing step. In this way, measured variables from different process sequences can preferably be brought into relation with one another.
The installation and/or the method preferably have one or more of the following features:
The glass pane and/or useful part is/are processed in a substantially horizontal position, in particular in at least one of the processing steps comprising cutting, breaking, grinding and, if provided, drilling.
The useful part that can be produced can have any contour. The contour can thus optionally be rectangular or non-rectangular. A rectangular useful part therefore forms a quadrilateral having right-angled corners. In the case of a non-rectangular useful part, corners and edges of any shape can be provided; in particular, the corners can be rounded.
The control device is configured in such a way that, using the cutting device, the glass pane can be provided with at least one auxiliary cutting line in addition to a cutting line that is intended to produce the contour of the useful part, along which auxiliary cutting line the edge region of the glass pane that does not belong to the useful part is to be divided.
The installation is configured to form a control loop during cutting, breaking, grinding and/or, if provided, drilling. In particular, the measurement signals supplied by the measuring devices can be continuously evaluated by the control device in order to repeatedly generate correction signals with which the device active in the corresponding processing step can be controlled in an adapted manner.
The at least one cutting tool of the cutting device may comprise a cutting wheel which is tiltable with respect to the vertical axis.
The cutting device may comprise a linear drive for moving the at least one cutting tool towards to and away from a glass pane.
The breaking device may comprise a linear drive for moving the at least one breaking tool towards to and away from a glass pane.
The measuring device for generating measurement signals may comprise at least one camera for imaging at least part of the glass pane and/or of the useful part, in particular the edge of the glass pane and/or of the useful part. The measuring device is e.g. applicable for generating measurement signals, which comprise a measured variable, which is detectable outside a processing step and which defines a state parameter of at least part of the glass pane. E.g. the measured variable may be based on detecting the edge of the useful part being a part of the glass pane, wherein said detection may be after cutting and breaking the glass pane and before grinding and/or after grinding of the edge of the useful part. The measuring device may be used to perform among others a quality check of the useful part produced and/or to feed back the outcome in order to adapt the further processing of the useful part and/or the processing of a subsequent glass pane and/or of a useful part. In a preferred embodiment, the measuring device comprises two or more cameras, which may be arranged above the glass pane and/or the useful part.
The invention is explained in the following by means of exemplary embodiments with reference to figures, in which:
Viewed in the direction of processing, the installation comprises the following successive stations:
Depending on the design of the installation, one or more of the stations 1-5 can be integrated in a single machine. Individual stations 1-5 can also be provided in plurality.
A transfer device 90 is used to transfer the glass pane G or the useful part N between the individual stations 1-5, which transfer device in this case has longitudinal supports 91 and receiving devices 92 movably arranged thereon. The longitudinal supports 91 are held on support devices 93 resting on the ground. A receiving device 92 has a vertically movable rack having, for example, one or more suction cups to be able to hold the glass pane G or the useful part N. The rack can also be pivotable about one or more axes.
In
In
The conveyor belt 22 is placed around deflection rollers 25, at least one of which can be driven. On the one hand, said conveyor belt serves as a support surface for the glass pane G during processing thereof, during which the conveyor belt 22 is at rest. Said conveyor belt is provided with holes 22a through which air can be sucked out by means of a vacuum pump and an underpressure can thus be generated, which causes the glass pane G to be processed to be held in place. On the other hand, the conveyor belt 22 can be moved in the Y direction to be able to transport the broken-off glass shards to an adjoining collection basin 26, for example a pit in the floor or a container (see
On the frame 21, longitudinal rails 27 are arranged on two longitudinal sides, along which longitudinal rails the bridge 23 can be moved, for example by means of linear drives. The bridge 23 has a transverse rail 28 on which the carriage 24 is arranged such that it can be moved, for example by means of a linear drive.
The cutting tool 30 and breaking tool 40 arranged on carriage 24 can be seen in more detail in
During the cutting process (also called “scoring”), as shown in
A tiltable cutting wheel as mentioned above may be beneficial for producing a useful part N which has at least one internal opening. Such an opening is defined by a contour situated within the useful part N. By tilting the cutting wheel a scoring line can be provided which, after breaking, leads to a broken edge, which is outwardly inclined so that the portion broken out can be lifted away from the useful part N, or which is inwardly inclined so that the useful part can be lifted away from the portion broken out. Thus, it is possible to provide a useful part, which has one or more openings inside the useful part, in particular a useful part being of a ring type, whose outer outline and inner outline may be round, rectangular or a combination of curved and straight portions.
Optionally, an ultrasonic actuator can be provided on which the cutting tool 30 is mounted and which leads to a greater scratch depth and allows greater speeds when the scoring line is produced. Furthermore, conclusions can be drawn about the scoring process through the interaction of the glass pane G and/or the scratching process via a change in the ultrasonic vibration (e.g. amplitude, phase and/or frequency).
As an alternative or in addition to a cutting wheel, the cutting device can have a laser for generating a laser beam as a cutting tool. To cut the glass pane G, holes can be drilled along the cutting lines, for example, using the laser.
As
It is also conceivable to provide other shapes for the breaking body, for example in the form of a roller. The breaking tool 40 can also be designed as a ram that can be tilted such that the angle between the ram and the surface of the glass pane G can be adjusted. Thus, the ram can also exert a force on glass pane G that does not necessarily act perpendicular to the glass surface. The angle can then, for example, be controlled specifically in the breaking direction, and/or if the breaking does not run in the optimal direction, this can be corrected and optimized by means of the orientation of the ram and/or the size by which the angle deviates from the vertical, in particular in a dynamic manner during breaking along the shape to produce the useful part. It is also conceivable to provide an ultrasonic actuator on which the breaking tool 40 is mounted. The part of the breaking tool 40 with which the glass pane G is contacted can be made of various materials such as metal, plastic, rubber having a certain hardness, etc.
During the breaking process, as shown in
A stationary surface 42, which is arranged below the conveyor belt 22 and rests on a support surface 43, is used as a mating surface in this case. The stationary surface 42 is designed, for example, as a template whose shape is adapted to the contour K of the useful part N and can be replaced if necessary. The template 42 can also already be attached during the cutting process, see
It is also conceivable to provide at least one movable surface as a mating surface, which movable surface supports the useful part N from below during breaking. For example, at least one lower breaking body can be provided that is arranged in such a way that it can be moved in a radial direction on a table that can be rotated about a center of rotation. As a result, the lower breaking body can be moved in the plane and positioned below the conveyor belt 22 in accordance with the respective position of the breaking body 40 in order to support the glass pane G in such a way that, as mentioned above, a moment can be exerted on the edge region B.
However, the breaking body below the conveyor belt 22 does not necessarily have to be present. For example, a hard or soft base can be provided.
The breaking body 40 can be designed in such a way that it contacts the glass pane G not only at one point, but along a line and/or plane. To be able to align this linear or planar contact surface in a targeted manner during the breaking process, the breaking body can be configured to be tiltable about one or more axes.
The breaking tool 40 need not necessarily have a breaking body or other mechanical object. A device for heating and/or cooling the glass pane G can also serve as a breaking tool. For example, the device can be used to produce at least one structure as a breaking tool, which structure is liquid, gaseous and/or in the form of light. Particular embodiments of the device include the application of a cooling spray, a CO2- and/or a N2-laser. The device may be configured such that it serves as a cutting tool 30 and a breaking tool 40.
The edge of the useful part N, which is the circumferential outer region between the upper side and underside of the useful part N, is ground at the subsequent station.
The machine also comprises an electric motor 55 for driving the grinding tool 60. The electric motor 55 and the grinding tool 60 are arranged on a carriage 56 that can be moved along a rail 57 as a guide by means of a drive 58. In this case, the electric motor 55 is designed, for example, as a spindle motor in order to set the grinding tool 60 in rotation. Said grinding tool is designed, for example, as a one-piece or multi-piece grinding wheel. The shape of the grinding wheel 60 is chosen in such a way that the edge of the glass pane N has the desired profile as a result of the grinding. In
The grinding tool 60 is held on a grinding spindle 61 and surrounded by a housing 62 that serves as a splash guard for the coolant supplied, for example cooling water. The housing 62 has a continuous slot 62a on the side, through which the edge region of the useful part N protrudes into the interior of the housing and can thus be machined by the grinding tool 60. The housing 62 also has internal channels 62b through which coolant can be supplied to the grinding tool 60. The coolant can be collected at the bottom of the housing 62 and sucked off by means of a suction device that has a suction tube 64 and a cyclone separator 63 in this case.
A cooling device 65 can be provided for cooling the electric motor 55 and/or the grinding spindle 61.
In the machine 50 shown here, the spatial position of both the support 52 and the grinding tool 60 can be changed. In order to achieve a relative movement between the useful part N and the grinding tool 60, the following embodiments are also conceivable:
The support 52 is stationary and the grinding tool 60 is arranged such that it can be moved around the edge of the useful part N.
The grinding tool 60 is stationary and the support 52 is movable, such that the edge of the useful part N can be moved past the grinding tool 60.
In the case of the machine 50, more than one grinding tool 60 can also be provided to be able to grind the useful part N at a plurality of locations at the same time and/or to be able to grind a plurality of useful parts N at the same time.
Coming back to
An ultrasonic actuator can be provided on the holder for holding the useful part N in order to cause the holder to oscillate. This allows the drilling speed to be increased. Also, the precision and/or fineness of the drilling surface and also the service life of the drilling tool 71 can be improved.
In order to allow a more optimal process flow, the system has a measuring device that supplies measurement signals at different positions in the installation and at different times. These measurement signals, which define specific measured variables of the respective machine 20, 50, 70 and of the glass pane G/the useful part N, can be processed by the control device 100-103 to form correction signals that affect the process flow of a glass pane that is currently being processed or that is subsequently processed into a finished glass pane.
To generate the measurement signals, sensors can be provided that are arranged in a stationary and/or movable manner. Measurement signals can also be those that include a measured variable that specifies a process parameter of at least one component of the machine 20, 50, 70 while a processing step is being carried out.
Sensors 129, 130, 136, 137, 170-172, 180 are shown by way of example in
Sensors 136 and 137 are each arranged on a receiving device 92, for example. The respective sensor 130, 136, 137 is used, for example, to generate measurement signals that comprise a measured variable that defines a state parameter of at least part of the glass pane G. The measurement by the sensor 136, 137 can take place when the glass pane G or the useful part N has not yet been picked up by the receiving device 92. In this case, the receiving device 92 can move relative to the glass pane G or the useful part N. Alternatively or additionally, the measurement can be carried out when the glass pane G or the useful part N has been picked up by the receiving device 92.
The sensors 170-172, 180 are arranged on the machine 70 for drilling.
Sensors 131-133 are shown by way of example in
In addition to sensors 132, 133, sensor 135, which is arranged on the cutting tool 30, is shown by way of example in
Sensors 152-154 are indicated in
Sensors 150-152 and 160 are indicated in
Using the measuring device, measurements can be carried out both during the execution of a processing step (cutting, breaking, grinding or drilling) (hereinafter also referred to as “dynamic measurement”) and outside a processing step, i.e., before and/or after a processing step and thus when the glass pane G or the useful part N is not being processed (hereinafter also referred to as “static measurement”). The dynamic measurement is carried out in such a way that the temporal course of a process parameter of at least one component of the device that is active during processing, for example the corresponding tool 30, 40, 60, 71, and/or the temporal course of a process parameter of the glass pane G and/or of the useful part N is recorded. The measurement is carried out in such a way that it is carried out as a function of the relative position of the tool 30, 40, 60, 71 in relation to the contour K. This allows the process parameters to be recorded and evaluated, among other things in case of certain contours, for example in case of tight radii. The static measurement is carried out in such a way that a state parameter of the glass pane G or the useful part N and/or at least one tool 30, 40, 60, 71 is recorded.
a) Embodiments of dynamic measurements in the individual processing steps are explained below.
One or more of the following measured variables can be recorded during cutting as a function of time and the relative position of the cutting tool 30 in relation to the contour K:
For example, a measured variable is recorded that is based on the measurement of the force that the cutting tool 30 exerts on the glass pane G. The force can be, for example, the normal force and/or a transverse force thereto. To measure the force, for example, the pressure on the pneumatic system can be recorded in a pneumatic actuator for raising and lowering the cutting tool 30, and/or the current of the drives with which the bridge 23 and carriage 24 are moved can be evaluated. Alternatively or additionally, a force measuring sensor can be provided, for example a sensor that acts piezoelectrically, capacitively, and/or piezoresistively.
For example, a measured variable is recorded that is based on the measurement of the speed at which the cutting tool 30 is moved along the glass pane G. For this purpose, for example, the signals with which the drives for moving the bridge 23 and the carriage 24 for moving the cutting tool 30 are controlled can be tapped. A respective drive has, for example, a displacement or position measuring system, by means of which position data that can be directly evaluated can be supplied.
When a cutting wheel is provided which is tiltable, an additional axis of movement defined by a tilting angle is provided. A measured variable may be recorded that is based on the tilting angle of the cutting wheel (see angle a in
For example, the target position of an axis of movement of the machine 20, which specifies a movement during cutting, is recorded as the first measured variable and the actual position during cutting is recorded as the second measured variable. The deviation between the actual and target position results in the contouring error of the axis of movement. If the characteristics of the control circuit are known and can be described mathematically, conclusions can be drawn, for example from the contouring error, about the magnitude and sign of an external force.
For example, at least one sensor 131 is provided for measuring sound emission as a measured variable. The sensor 131 can be a microphone, for example, that is used to detect airborne noise. It is also conceivable to use a plurality of sensors 131 of the same type in order to detect spatial and/or temporal differences in sound emission. Alternatively or additionally, the sensor 131 can be used to detect structure-borne noise and be configured in such a way that it contacts the glass pane G, for example directly, for example from above or from below through a hole in the conveyor belt 22, and/or the sensor 131 contacts a component that contacts the glass pane G, for example the conveyor belt 22 or the cutting tool 30. During cutting, the action of the cutting tool 30 on the glass sheet G generates a sound. From the measurements of said sensor, it is possible to recognize, for example, if an undesired breakout next to the scoring line (“chipping”) can occur at a specific point on the contour K. The measurement of the sound allows the pressure of the cutting tool 30 on the glass pane G, among other things, to be continuously adjusted during the cutting process if required.
For example, the temporal course of the quantity of cutting oil that is supplied to the cutting tool 30 is measured. This can be done, for example, by means of an optical sensor 132 in the form of a camera, see
At least one sensor 133 is provided, for example, with which the thickness of the glass pane can be measured at different positions. A feeler, for example, that is arranged on the carriage 24 is suitable as the sensor 133, see
An acceleration sensor 135 is provided, for example, that serves to measure vibrations and is arranged, for example, in the vicinity of the cutting tool 30, see
It is also possible, for example, to provide an exciter in order to excite the cutting tool 30, for example in the ultrasonic range, and to measure the temporal course of the energy that is required by the exciter.
In order to determine the relative position of the cutting tool 30 in relation to the contour K in the case of the measured variables specified above, the signals with which the drives for moving the bridge 23 and the carriage 24 for moving the cutting tool 30 and for raising and lowering the cutting tool 30 are controlled can be tapped and evaluated, for example.
One or more of the following measured variables can be recorded during breaking depending on the time and the relative position of the at least one breaking tool 40 in relation to the contour K:
For example, a measured variable is recorded that is based on the measurement of the force that the breaking tool 40 exerts on the glass pane G. The force can be, for example, the normal force and/or a transverse force thereto. To measure the force, for example, the pressure on the pneumatic system can be recorded in a pneumatic actuator for raising and lowering the breaking tool 40, and/or the current of the drives with which the bridge 23 and carriage 24 are moved can be evaluated. Alternatively or additionally, a force measuring sensor can be provided, for example a sensor that acts piezoelectrically, capacitively and/or piezoresistively.
For example, a measured variable is recorded that indicates the positions and, optionally, orientation and tilt angle of the breaking tool 40 at which it contacts the glass pane G during breaking, and/or that indicates the speed at which the breaking tool 40 is moved when it contacts the glass pane G. For example, the breaking tool 40 for breaking off the edge region B is lowered at various points onto the glass surface and/or, after being lowered, is moved along the edge region B along a specific path at a specific speed. For this purpose, for example, the signals with which the drives for moving the breaking tool 40 are controlled can be tapped.
For example, at least one sensor for measuring sound emission is provided as a measured variable. For example, the sensor 131 or a plurality of the sensors 131 can be used as a sensor. During the breaking process, the action of the breaking tool 40 on the glass sheet G generates a sound. From the measurement of said sensor, it is possible to recognize, for example, when the crack in the glass pane G propagates to the rear side. The measurement of the sound then allows the pressure of the breaking tool 40 on the glass pane G to be adjusted, for example, during the breaking process if required. The acoustic measurement also allows unwanted chipping to be detected at a specific point on the contour K, in particular at the transition from the broken edge to the glass front side or rear side, and other anomalies and thus to deduce a quality defect in the broken edge.
An optical sensor, for example a camera, can be used to detect how the break runs along a scoring line and/or how the splinters form at the transition from the break edge to the upper side of the glass.
For example, an acceleration sensor is provided that serves to measure vibrations. For example, a sensor in the form of acceleration sensor 135 can be used for this purpose.
In order to determine the relative position of the breaking tool 40 in relation to the contour K in the case of the measured variables specified above, the signals with which the drives for moving the bridge 23 and the carriage 24 for moving the breaking tool 40 are controlled can be tapped and evaluated, for example. Alternatively or additionally, the position of the breaking tool 40 can be recorded by a camera and determined by means of image processing.
One or more of the following measured variables can be recorded during grinding as a function of time and the relative position of the grinding tool 60 in relation to the contour K:
For example, a measured variable is recorded that is based on the measurement of the force that the grinding tool 60 exerts on the useful part N. The force can be, for example, radial and/or transverse thereto and/or can comprise the torque of the grinding tool 60. For this purpose, for example, the respective current that the drives need to move the support 52 and the grinding tool 60 can be measured and evaluated. Alternatively or additionally, a force measuring sensor can be provided, for example a sensor that acts piezoelectrically, capacitively and/or piezoresistively.
At least one sensor is provided, for example, with which the force that is exerted on the support 52 during grinding can be detected. For example, a suction cup 53 is equipped with such a sensor 150, see
For example, at least one sensor 151 is provided for measuring sound emission as a measured variable, see
For example, a measured variable is recorded that is based on the measurement of the energy used to drive the grinding tool 60. For example, the current used to drive the electric motor 55 can be detected. The measurement of said energy may be used to detect e.g. the occurrence of firing during the grinding process. Another measured variable may be based on detecting the vibrations of the bearing of the electric motor 55 which are related to the specific forces occurring in the grinding process.
For example, at least one optical sensor 152 is provided (see
It is also conceivable to record a measured variable that the coolant discharged from the grinding tool 60 has, for example the temperature and/or chemical composition of the coolant.
At least one sensor 153 is provided, for example, that measures the vibration and/or the sag of the useful part N during the grinding process, see
For example, an acceleration sensor is provided that is arranged in the vicinity of the grinding tool 60 and with which vibrations of the useful part N, in particular in the Z direction, can be detected.
At least one temperature sensor 154 (see
For example, the target position of an axis of movement of the machine 50, which specifies a movement during grinding, is recorded as the first measured variable and the actual position during grinding as the second measured variable. The deviation between the actual and target position results in the contouring error of the axis of movement. If the characteristics of the control circuit are known and can be described mathematically, conclusions can be drawn, for example from the contouring error, about the magnitude and sign of an external force.
It is also conceivable to detect the current used by the drive moving the grinding tool 60 the Y axis, which current may indicate an imbalance of the grinding tool 60.
In order to determine the relative position of the grinding tool 30 in relation to the contour K in the case of the measured variables specified above, the signals with which the drives for moving the grinding table 51 and the grinding tool 30 are controlled can be tapped and evaluated. Alternatively or in addition, the position of the useful part N, in particular in the Z direction, can be detected by means of a laser distance sensor and/or a capacitive sensor.
One or more of the following measured variables can be recorded during drilling as a function of the time and the relative position of the drilling tool 71 in relation to the contour K:
For example, a measured variable is recorded that is based on the measurement of the force that the drilling tool 71 exerts on the useful part N. The force can be, for example, axial and/or transverse thereto and/or can comprise the torque of the drilling tool 71. For this purpose, for example, the respective current that the drives need to move the drilling tool 71 can be measured and evaluated. Alternatively or additionally, a force measuring sensor can be provided, for example a sensor that acts piezoelectrically, capacitively, and/or piezoresistively.
For example, at least one sensor 170 is provided for measuring sound emission as a measured variable, which sensor, for example, contacts the useful part N, see
For example, a measured variable is recorded that is based on the measurement of the energy used to drive the drilling tool 71. For example, the current used to power the electric motor for the drill can be detected.
At least one sensor 171 is provided, for example, that measures the vibration of the useful part N during the drilling process, see
At least one temperature sensor 172 (see
It is also conceivable, for example, to record the relative depth of the bore. For example, it is conceivable to dynamically record countersinking during drilling by measuring the current that is required to drive the drilling tool 71 and that increases during countersinking, and/or vibrations and/or noise, etc. As a result, the countersink depth can be controlled very precisely based on the feedback from the drilling tool.
b) Embodiments of static measurements outside a processing step are explained below.
One or more of the following measured variables can be recorded before cutting:
At least one optical sensor is provided, for example, with which the dimensions of the glass pane G can be detected. For this purpose, for example, a sensor 136 in the form of a camera and/or a laser is provided at the first station 1 and arranged, for example, on the receiving device 92, see
At least one weighing sensor 137 is provided, for example, with which the weight of the glass pane G can be determined and that is arranged, for example, on the receiving device 92, see
A temperature sensor, for example, is provided on the transfer device 90, for example, in order to detect any changes in length and, among other things, to correct the position in which the glass pane G is to be placed on the machine 20.
At least one sensor is provided, for example, with which the thickness of the glass pane can be measured at different positions. The sensor 133 at the second station 2 can be used for this purpose, for example.
At least one sensor is provided, for example, in order to determine the position of the glass pane G relative to a predetermined coordinate system. One or more of the sensors 132, 133, 136 can be used for this purpose, for example.
If a cutting wheel is used as the cutting tool, at least one sensor can be provided in order to determine the sharpness of the cutting wheel.
One or more of the following measured variables can be recorded after cutting:
At least one optical sensor 132 is provided, for example, with which the shape, for example the width and/or depth, and/or the geometric position of the furrow that forms a scoring line is detected. The geometric position of an auxiliary scoring line, in particular where it meets the scoring line defining the contour K, can also be recorded. A camera, for example, that is arranged on the carriage 24 is suitable as the sensor 132, see
At least one device is provided, for example, that comprises, for example, the optical sensor 132 in the form of a camera that is equipped with a polarization filter and that is used to detect mechanical stresses in the glass pane G by means of image processing.
The optical sensor 132 in the form of a camera can also be used, for example, to detect the trace of cutting oil on the upper side of the glass.
One or more of the following measured variables can be recorded before breaking:
At least one optical sensor is provided, for example, in order to detect the shape of the broken edge of the useful part N. For this purpose, for example, the sensor 132 can be used in the form of a camera. Alternatively or in addition, it is also possible to use a light source, for example a laser, to record the reflectivity of the broken edge. By measuring the broken edge, it is possible to determine where there are undesired deviations from the ideal edge, i.e., from an edge that is ideally perpendicular to the upper side of the glass. The formation of splinters at the transition from the break edge to the upper side of the glass can also be recorded.
At least one optical sensor is provided, for example, with which the dimensions of the useful part N can be detected. For this purpose, for example, the sensor 132 can be used in the form of a camera and/or a laser.
At least one weighing sensor is provided, for example, with which the weight of the useful part N can be determined. For this purpose, for example, the weighing sensor 137 on the receiving device 92 can be used.
It is also conceivable to analyze the waste pieces (borders) that are broken off the glass pane. Analyses and conclusions about the cutting/breaking process can be made based on the broken-off edges. For example, it is possible to analyze whether a long straight edge breaks off in one piece or whether there are a plurality of sections or what the broken edge of a waste piece looks like, etc.
One or more of the following measured variables can be recorded after grinding:
The optical sensor 152 is used to detect at least one of the following parameters:
The roughness of the glass edge can also be detected using mechanical measuring sensors, laser reflection measurement, cameras including image processing and/or a colorimeter.
The dimensions of the useful part N can also be detected by means of a camera and image processing, mechanical measuring sensors, calipers and/or laser distance measurement.
The position of the glass edge in the Z direction can be determined e.g. by means of the measuring device as described below in relation to
At least one weighing sensor is provided with which the weight of the ground useful part N can be determined. For this purpose, for example, the weighing sensor 137 on the receiving device 92 can be used.
At least one sensor is provided, for example, with which the thickness of the glass pane can be measured, for example at the intended drilling locations. A feeler that is arranged at the drilling station 4, for example, is suitable as a sensor.
At least one optical and/or tactile sensor 160 is provided, for example, in order to detect the geometry of the grinding surface of the grinding tool 60. For example, said grinding tool is designed as a grinding wheel having a specific groove profile. The groove depth, for example, can be detected by means of the sensor 160 in order to adapt the feed of the grinding tool 60 accordingly the next time a useful part N is machined.
It is also conceivable to measure the temperature that has set in on the grinding tool 60, in particular a grinding wheel body, after the grinding process. With increasing blunting of the geometrically undefined cutting edges (seen across a plurality of glass panes), there is a higher proportion of friction, which leads to more heat.
One or more of the following measured variables can be recorded after drilling:
For example, at least one optical sensor 130 is provided (see
The roughness of the drilled hole can also be recorded by means of a mechanical sensor, laser reflection measurement, a camera including image processing and/or a colorimeter.
The dimensions of the drilled hole can also be detected by means of a camera and image processing, mechanical measuring sensors, calipers and/or laser distance measurement.
At least one weighing sensor is provided, for example, with which the weight of the ground and drilled useful part N can be determined. For this purpose, for example, the weighing sensor 137 on the receiving device 92 can be used.
At least one optical and/or tactile sensor 180 is provided, for example, in order to record the length of the drilling tool 71.
In general, at least one sensor, for example an optical sensor such as a camera, laser, etc., can be provided after a processing step in order to record the dimensions of the glass pane G or the useful part N, the shape of the broken or ground edge and the shape of any drilled holes. In particular, automatic quality control of the produced useful part N can be carried out after the last processing step.
The cameras 152a and 152b are arranged above the glass front side, whereas the mirror unit 152f and the illumination unit 152g are arranged below the glass rear side. This arrangement takes into consideration that the space below the useful part N is limited when the latter is positioned e.g. on the support 52 of the machine 50. The illumination unit 152g may also be arranged above the glass front side.
The provision of the laser sensor 152e is optional. It may be omitted or replaced by an additional camera.
The measuring device may comprise monitoring means, e.g. one or more position sensors, in order to avoid an unwanted collision with part of the machine 50 and/or the useful part N/glass pane G during movement of the measuring device.
The components 152a-152e may be arranged on a first carrier and the components 152f, 152g may be arranged on a second carrier, whereas the two carriers may be connected via a connection 152h.
Preferably, the components 152a-152e are positioned such that they sense the same region on the glass edge and are moved such that said region follows along the glass edge as the latter is rotated.
The cameras 152a and 152b are applicable to detect one or more of the following characteristics:
One possible procedure of observing a useful part N arranged on the machine 50 by the cameras 152c, 152d is as follows: The useful part N is fixed on the support 52 of the rotatable grinding table 51. During rotation of the useful part N cameras 152c and 152d are moved, e.g. linearly, and image the glass edge. The provision of two cameras 152c and 152d arranged at an angle has the effect that, as the useful part N is rotated, always one of the cameras 152c or 152d is positioned substantially in front of the glass edge so that the distortion of the imaged glass edge is reduced and the glass edge is sufficiently illuminated by the illumination unit 152g, see
The illumination unit 152g is configured such the illumination intensity is as uniform as possible also for glass edges which are not right-angled.
Here, the ring-like illumination 152g is configured such that it has a diameter as small as possible so that the useful part N can be supported close to its edge by support 52 and a collision of the support 52 with the measuring device is avoided when the cameras 152c, 152d are moved. Here, a laser sensor 152e in form of a laser position measuring device is provided to scan the glass edge as the latter is imaged by the cameras 152c, 152d. In an alternative embodiment not all of the components 152c-152e are provided, e.g. the cameras 152c, 152d only or the laser sensor 152g only.
Instead of the provision of two cameras 152d, 152e which are movable only linearly, it is also conceivable to provide only one camera 152d or 152e which is arranged in a rotatable and linearly displaceable manner.
One or more of the following characteristics can be detected by the measuring device as described:
The sensing accuracy of the components 152a-152e is chosen depending on the application. In one embodiment, the components 152a, 152b, 152e have a high accuracy, which may be in the range of view micrometers, e.g. 1-2 micrometers. Ideally, the cameras 152a, 152b are arranged perpendicular to the glass surface so that images are taken which allow a direct measurement of dimensions.
Cameras 152c, 152d may be less expensive ones, e.g. a webcams or industrial cameras, and may record images which allow only a qualitative observation of edge. In one embodiment, the cameras 152c, 152d are calibrated by using calibration images which are taken e.g. by at least one of the cameras 152a, 152b having an increased imaging accuracy. The calibration images may be produced e.g. by imaging a calibrating object which has predetermined dimensions, e.g. a template with precise markings. Once calibrated, the cameras 152c, 152d allow a quantitative measurement similar as the more expensive cameras 152a, 152b. Thus, the latter may be replaced by cheaper cameras such as cameras 152c, 152d when calibrated.
In order to synchronize the images taken by the different cameras 152a-152d, a timer may be provided. A time signal supplied by the timer causes on the one hand each image to be provided with a timestamp and on the other hand the controller 102 of machine 50 to record the machine coordinates of the moving components. By combining the data on the timestamps and the machine coordinates the images taken can be mapped on the geometry of the glass edge. Thereby, specific features as explained above can be located on the glass edge.
In one embodiment, a cleaning unit is provided for cleaning the glass edge before applying the measuring device. Such a cleaning is beneficial as the glass may be contaminated with cutting oil, cooling water, glass dust or other impurities, which may impede the optical observation by the cameras 152a-152d. The cleaning unit is arranged on the machine 50 such that it is movable relative to the grinding tool in a similar way as the measuring device.
Positioning the measuring device on the machine 50 allows the monitoring of the cutting, breaking and grinding process. The cutting and breaking process can be evaluated before the useful part N is ground and the grinding process can be evaluated after the useful part N is ground. Both steps of evaluation can be performed without removing the useful part N from the support 52 so that an increased precision in the evaluation can be achieved.
The measurement signals supplied by the measuring device are received by the control device 100-103 and evaluated to form measurement data. The control device is equipped, for example, with an artificial intelligence algorithm that allows the measurement data to be evaluated and one or more correction signals to be formed with which the control of the machines 20, 50, 70 during processing of the current glass pane G and/or useful part N can be adjusted during a current or subsequent processing step or during processing of a subsequent glass pane G and/or useful part N, the adjustment taking place as a function of the relative position of the tool 30, 40, 60, 71 in relation to the contour K.
In steps A1-A3, B1-B3, measurement signals are generated that comprise measured variables and that are fed to the control device C, as indicated by the arrows P1. The control device C, which is, for example, the control device 100-103, evaluates the measured variables and reacts to the machines 20, 50 with corresponding correction signals, such that the processing B1, B2, B3 can be adapted, as indicated by the arrows P2.
In processing step B1, drives are controlled that cause the cutting tool 30 to move (field B11 in
As explained above, measured variables can be recorded in step A1, for example the depth of the scoring line, chipping at the transition to the front of the glass, etc.
In processing step B2, drives are controlled that cause the breaking tool 40 to move (field B21 in
As explained above, measured variables can be recorded in step A2, for example unevenness of the broken edges, damage to said edges (in particular conchoidal fractures), size of the useful part N, etc. For example, the magnitude of the conchoidal fractures and frequency of said conchoidal fracture magnitude can be determined over a specific length of the glass edge. Measured variables may define further properties of the shape of the edge which the useful part N broken out has such as the occurrence of half-penny cracks, in particular their shape, frequency and depth, and/or microcracks and/or the angle of the edge (over- or underbreack) and/or unwanted protrusions. The measured variables may be used to adjust the parameters for cutting such that e.g. the half-penny cracks with desired properties are produced.
In processing step B3, drives are controlled that cause the grinding tool 60 and the support 52 to move (field B31 in
As explained above, measured variables can be recorded in step B3, for example power consumption of the drives, force, vibrations, sound, temperature, etc. (field B33 in
As explained above, measured variables can be recorded in step A3, for example the shape of the ground edge and the position thereof, roughness of said edge, damage to said edge (in particular conchoidal fractures, scratches), size of the useful part N, etc. Measured variables may define further properties of the shape of the ground edge such as the occurrence of regions which are not correctly ground and firing marks, in particular regions of melted glass produced by an overheat during grinding.
The measuring device as described above in relation to
The control device C is preferably equipped with an algorithm based on artificial intelligence, in particular an algorithm for machine learning and/or for pattern recognition. To obtain training data, test runs are carried out, for example, in which the scoring lines and the broken and/or ground edges are recorded and evaluated in steps A1-A3, for example by means of the existing measuring device. The trained algorithm can then be used to evaluate the measurement data, which is generated later in the current process flow, and to generate corresponding correction signals.
The memory is, for example, an internal data memory of the system, and/or the system has an interface for exchanging data with an external data memory, for example via a network.
Training data can also be provided by comparing measured variables from the various steps A1-A3, B1-B3 with one another. For example, the measurement in step A2 reveals that the broken-off edge is excessively chipped in the case of a tight curve. The algorithm of the control device C can therefore generate correction signals that, during processing of a subsequent glass pane, adjust, for example, the pressure that the cutting tool 30 exerts on the glass surface when cutting a tight curve, and then in step A2 analyze whether the chipping on the broken-off edge is reduced.
Training data can also be provided by evaluating and storing measurement data on dynamic and static measured variables from previously processed glass panes.
The parameters resulting from the desired shape and size of a useful part N can also serve as training data. For example, in step A2 it is determined that the broken edge is too far away from the desired contour K, such that too much has to be removed in processing step A3. The algorithm of the control device C can therefore set the scoring line closer to the desired contour when a subsequent glass pane is processed, such that less grinding has to be done.
Overall, the algorithm of the control device C allows the process sequences to be optimized during cutting and breaking (field M1 in
For example, the proportion of broken-off glass, the quality of the useful part, and the processing time can be optimized.
Alternatively or additionally, it is also conceivable to equip the control device C with a physical model (field M3 in
By providing “artificial intelligence”, the installation is capable of learning and can constantly develop further. It is therefore able to optimize itself independently. The installation can also be operated more autonomously. The demands on the operating personnel and their workload are therefore reduced.
By providing the measuring device, the installation can obtain a comprehensive picture of the process parameters and the results obtained (reactions of the glass during processing and properties of the processed glass).
Components that are already available as standard can also be used to design the measuring device. For example, the existing drives, in particular actuators, can supply usable measurement data.
The measuring device is configured in such a way that the measurement signals that are generated during an ongoing processing step are recorded at a sufficient temporal resolution. The temporal resolution of the measurement data is preferably at least 10 Hz and with increasing preference at least 100 Hz, at least 1000 Hz and at least 10 KHz. The control device C is accordingly configured to generate control signals that have a comparable temporal resolution. Said resolution is thus preferably at least 10 Hz and, with increasing preference, at least 100 Hz, at least 1000 Hz and at least 10 KHz. In this way, the control device C can make an adjustment to the control based on the measurement data during ongoing processing.
As explained above, various measured variables are conceivable:
The measurement data from the measuring device is collected, evaluated and preferably stored by the control device C. For evaluation, the control device C comprises an evaluation unit. Depending on the process and machine configuration, the control device C decides on targeted influence and the intensity with which said influence is exercised.
The control device C can, for example, intervene simultaneously (for example in fractions of a second) in dynamic, ongoing processes with the aim of optimizing them. Self-regulation can thus take place within the process.
The control device C can use previously determined and/or calculated information to adapt subsequent processes on the same workpiece.
The control device C can collect information and adjust parameters across a plurality of workpieces/batches.
It is possible to network the installation with other installations of the same type in order to share successful optimization with said other installations. The information obtained can also be made available for the purposes of product documentation and/or as input for upstream and downstream process chains.
The glass that can be processed using the installation is glass panes that are used in the following applications, among others: vehicles, architecture, displays, solar panels, kitchens (in particular oven doors and cooktops). The glass pane can also be a ceramic glass.
Automatic quality control can also be carried out by measuring the glass pane G or the useful part N outside of a processing step. However, said quality control is optional and may only be required initially. With the help of artificial intelligence, in particular machine learning and/or pattern recognition, conclusions can also be drawn indirectly about quality by evaluating the dynamic measured variables that are recorded during the processes.
The measuring device can be used to record static measured variables after a processing step (cutting, breaking, grinding or drilling), for example, as explained above, the condition of the broken/ground edge. The measured variables can be recorded in a position-resolved manner at least in part, preferably entirely along the circumference of the edge of the processed glass, and can be related to the measured variables that were recorded during the previous processing step as a function of the position of the tool in relation to the contour. The position resolution for the static measured variables is preferably at least the value from the product of the temporal resolution of the measurement during processing multiplied by the processing speed along the edge of the glass, particularly preferably at least 10% of said value.
By comparing static and dynamic measured variables, optimized process parameters can be found and one or more process steps can be better tailored to the requirements (for example, precision, tool wear, energy requirements, cycle time, etc.). For example, dynamic measured variables from two or more different processing steps, each followed by a quality measurement to obtain static measured variables, can be carried out and analyzed to be able to identify relationships that allow continuous improvement with regard to process parameters. Only one or a plurality of process parameters can be varied to find the optimization direction.
In a further embodiment, the measuring device of the installation can record other measured variables, such as changes in the glass properties, temperature fluctuations in the environment, etc., in order to achieve further optimization in production.
In one embodiment, the installation is optimized in such a way that a useful part having the desired contour can be produced right away, i.e., without going through test runs.
The recording and evaluation of measured variables also makes it possible to improve the cutting plan and/or breaking plan for processing subsequent glass panes. The cutting plan defines the contour of the at least one useful part and optionally one or more auxiliary cutting lines for defining a break in the unused edge region of the glass pane. The breaking plan specifies where and how a force should be applied to the cut glass pane to initiate breakage. The cutting plan and the breaking plan can be improved, for example, in that the portion of the edge of the glass pane that does not belong to the useful part N and is therefore broken off and/or ground down is reduced.
The measuring and control devices of the installation also allow for improvements in terms of monitoring, diagnostics and maintenance. This can be, for example, the state of the tool or another component of the machine, in particular the consumables (coolants, lubricants, energy consumption). With the measuring device, for example, one or more measured variables of the tool or another component of the respective machine can be recorded and, if necessary, related to the dynamic and/or static measured variables to be able to detect any undesirable deviations, in particular anomalies. The installation can be configured in such a way that, for example, a message is generated when a tool has become too worn and maintenance is therefore required.
A prediction can be made of tool wear and the correct time for tool replacement. Predictive maintenance and/or condition monitoring is therefore possible for both the tool and the machine. It is also possible to improve and preferably optimize control of the machine by adapting the machine parameters, such that the wear on the tool or other parts of the machine is reduced. For example, the drives can be controlled in such a way that acceleration and/or deceleration is optimized.
In one possible embodiment, the system has, for example, a processing device for shaping and/or sharpening the grinding tool 60. The control device 100-103 is configured in such a way that it activates the processing device as a function of at least one of the measured variables and/or the at least one measured state variable of the grinding tool 60. For example, the activation is such that the processing device specifies the force and/or speed of a sharpening stone for processing the grinding tool 60 and/or the frequency and/or duration of the sharpening process with the sharpening stone and/or that the grinding tool 60 is processed as a function of the shape of an edge of the sharpening stone. The sharpening process by the sharpening stone may be controlled e.g. based on the current used by the electric motor 55 and/or on the force with which the sharpening stone is pressed against the grinding tool 60. A linear drive may be provided for displacing the sharpening stone.
The actual sharpness of the grinding tool 60 may be determined e.g. based on the energy used for driving the grinding tool 60. For example, the current used by the electric motor 55 may be measured and integrated over the time during which the grinding tool 60 grinds the glass edge or a particular portion thereof. When said integrated current exceeds a predetermined threshold, then the grinding tool 60 is sharpened. Depending on the choice of the threshold, this sharpening may be initiated once or several times during the usual service life of the grinding tool 60.
In one embodiment, the grinding process is configured such that the grinding tool 60 is self-sharpened. The grinding tool is e.g. configured as a wheel comprising grains, such as diamonds, embedded in a matrix via bonding layers. The grinding process, e.g. the feeding of the grinding tool 60 towards the glass edge, may be controlled such that when grains are released from the wheel their bonding layers are also abraded, so that the next grains occur on the surface. In that way, no separate sharpening of the grinding tool 60 is needed. It conceivable to provide for an extra part on the useful part N which is grinded down by the grinding tool 60 in order to achieve a self-sharpening effect.
In an analogous manner as for the grinding tool 60, the actual sharpness of the drilling tool 71 may be determined e.g. based on the energy used for driving the drilling tool 71. For example, the current used by the drive may be measured and integrated over the time during which the drilling tool 71 drills a hole. When said integrated current exceeds a predetermined threshold, then the drilling tool 71 is sharpened by a sharpening device.
In one embodiment, the drilling process is configured such that the drilling tool 71 is self-sharpened.
From the preceding description, numerous modifications are accessible to a person skilled in the art without going beyond the scope of protection of the invention defined by the claims.
In the installation shown in the figures, cutting and breaking are performed on the same machine 20. Among other things, the components 23, 24, 27, 28 for moving the tools 30, 40 are therefore part of the cutting device for cutting the glass pane G as well as part of the breaking device for breaking the glass pane G. Alternatively, it is conceivable to design the system in such a way that cutting and breaking are carried out at different locations, such that the cutting and breaking device can have separate parts in order to move the cutting tool 30 and the breaking tool 40.
It is also conceivable to provide a machine with which a plurality of processes of cutting, breaking, grinding and, if provided, drilling can be carried out.
As described above a pneumatic actuator may be provided to move the cutting tool 30 or the breaking tool 40. Alternatively, a linear drive may be provided for moving tool 30, 40 towards to and away from a glass pane to be processed. A linear drive may allow for more precise movements and/or improved force control than a pneumatic actuator. Preferably, the linear drive includes at least one position sensor providing a signal on the stroke position and with it the position of tool 30, 40. The linear drive is configured such that the tool position can be determined when the tool 30, 40 contacts a surface. Thus, one can detect whether the tool 30, 40 is facing a glass pane or not.
In one embodiment, the linear drive is applied to measure the unevenness of the surface by which a glass pane is supported during cutting and/or breaking, e.g. the conveyor belt 22 of machine 20. The measured unevenness may be stored, e.g. in a look-up table, and may be taken into consideration when a thin glass pane, e.g. one with a thickness of less than 1 mm, is to be processed as its surface may not be perfectly plane when lying on an uneven support surface and thus may vary in the vertical direction.
In a further embodiment, the linear drive is applied to measure the thickness of a glass plane to be processed. This allows the starting position of the tool 30, 40 to be chosen closer to the glass pane. Thereby, the path can be reduced along which the tool 30, 40 is moved between the starting position and the position, in which the tool 30, 40 acts on the glass pane. Overall, the cycle time between two cutting and/or breaking processes can be reduced.
In another embodiment the same drive, preferably linear drive, may be applied to move alternatively the cutting tool 30 and the breaking tool 40 towards the glass pane.
In a further embodiment the mass of the mechanism for the cutting tool 30 is reduced by the provision of spring and/or magnetic means. Thereby, the forces occurring in the cutting process can be determined with reduced noise and loss.
By determining the position of the cutting tool 30, in particular by the provision of the linear drive as explained above, the sharpness of the cutting wheel may be determined. As the cutting wheel becomes less sharp, it will enter less deeply into the glass and thus the position is changed. Further, the sharpness of the cutting wheel may be determined by detecting vibrations of the cutting tool 30 during cutting.
| Number | Date | Country | Kind |
|---|---|---|---|
| 00706/21 | Jun 2021 | CH | national |
This application is the US national stage of PCT/EP2022/066434, filed Jun. 15, 2022 and designating the United States, which claims the priority of CH 00706/21, filed Jun. 17, 2021. The entire contents of each foregoing application are incorporated herein by reference.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2022/066434 | 6/15/2022 | WO |
