DE102020131851A1 - Procedure and transport arrangement - Google Patents

Abstract

Method (100) for a transport device (200), by means of which one or more than one transport item (102) is transported, the method (100) comprising: comparing (11) the transport process recorded at or from a first point in time with the transport process at or transport process recorded from a second point in time; and driving (13) a transport device (200) by means of which the transport process is carried out, based on a result of the comparison.

Description

Various exemplary embodiments relate to a method and a transport arrangement.

In general, a plurality of substrates can be transported one behind the other by means of a transport device, for example in a vacuum. Disturbances of the transport can occur, which can damage the transport device or the substrates, cause a jam or affect the process in some other way. Light barriers are conventionally used in order to be able to monitor and/or correct the transport.

According to various embodiments, it was clearly recognized that conventionally only part of the available information about the transport is ascertained/used. According to various embodiments, a method and a transport arrangement are provided which achieve that more information about the transport can be provided.

Conventionally, only the binary information about whether a substrate covers the light barrier or not is clearly determined. According to various embodiments, information about the transport is alternatively or additionally provided. The additional information is determined, for example, based on how the sensor signal output by the light barrier changes over time, e.g. substrate-by-substrate or substrate-bound. For example, it is determined whether the sensor signal (or its progression) of a light barrier changes from substrate to substrate, or whether the sensor signal (or its progression) of a substrate changes from light barrier to light barrier.

In this context, a transport arrangement is provided which provides a better sensor signal.

The sensor signal can have a better signal-to-noise ratio or a greater hysteresis when passing through the substrate, making it easier to provide additional information about the transport. Clearly, the beam path is aligned at an angle to the transport surface, so that the substrate provides a greater obstacle to the light. Compared to a horizontal light barrier, the oblique beam path is blocked by a larger area of the substrate, which makes it easier to detect particularly thin substrates. Compared to a vertical light barrier, the oblique beam path has a longer distance through the substrate, which makes it easier to detect substrates that are particularly transparent.

• 1 ein Verfahren gemäß verschiedenen Ausführungsformen in einem schematischen Ablaufdiagramm;
• 2 eine Transportanordnung gemäß verschiedenen Ausführungsformen in einer schematischen Seitenansicht oder Querschnittsansicht;
• 3 die Transportanordnung gemäß verschiedenen Ausführungsformen in einer schematischen Seitenansicht oder Querschnittsansicht;
• 4A bis 4C jeweils verschiedene Diagramme gemäß verschiedenen Ausführungsformen des Verfahrens; und
• 5A bis 5C jeweils verschiedene Diagramme gemäß verschiedenen Ausführungsformen des Verfahrens.

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• 1 a method according to various embodiments in a schematic flowchart;
• 2 a transport arrangement according to various embodiments in a schematic side view or cross-sectional view;
• 3 the transport arrangement according to various embodiments in a schematic side view or cross-sectional view;
• 4A until 4C respectively different diagrams according to different embodiments of the method; and
• 5A until 5C each different diagrams according to different embodiments of the method.

In the following detailed description, reference is made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. In this regard, directional terminology such as "top", "bottom", "front", "back", "front", "rear", etc. is used with reference to the orientation of the figure(s) being described. Because components of embodiments can be positioned in a number of different orientations, the directional terminology is used for purposes of illustration and is in no way limiting. It is understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present invention. It is understood that the features of the various exemplary embodiments described herein can be combined with one another unless specifically stated otherwise. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims.

Within the scope of this description, the terms “connected”, “connected” and “coupled” are used to describe both a direct and an indirect connection (e.g. ohmic and/or electrically conductive, e.g. an electrically conductive connection), a direct or indirect connection and a direct or indirect coupling. In the figures, identical or similar elements are replaced with identical ones Reference numerals provided, where appropriate.

According to various embodiments, the term "coupled" or "coupling" can be understood in the sense of a (e.g. mechanical, optical and/or electrical), e.g. direct or indirect, connection and/or interaction. For example, several elements can be coupled to one another along an interaction chain, along which the interaction (e.g. light output) can be exchanged, e.g. light (then also referred to as optically coupled). For example, two coupled elements can exchange an interaction with each other. According to various embodiments, "coupled" may be understood to mean a mechanical (e.g., physical) coupling, such as by means of direct physical contact. A clutch may be configured to transmit mechanical interaction (e.g., force, torque, etc.).

Controlling can be understood as intended influencing a current state, for example the state of a system or an operation (also referred to as a process). The current state (also referred to as the actual state) can be changed according to a specification (also referred to as the target state). Regulation can be understood as controlling, whereby a change in status due to disturbances is also counteracted. Clearly, the controller can have a forward-pointing control path and thus clearly implement a sequence control that converts an input variable (e.g. the specification) into an output variable. However, the controlled system can also be part of a control circuit, so that a control is implemented. In contrast to the purely forward-oriented sequence control, the regulation has a continuous influence of the output variable on the input variable, which is caused by the control loop (also referred to as feedback). In other words, regulation can be used as an alternative or in addition to the control, or regulation can take place as an alternative or in addition to the control.

The state of the system or process can be specified as a point (also referred to as an operating point or operating point) in a space (also referred to as a state space) that is spanned by the variable parameters of the system or process (also referred to as operating parameters). The state of the system or process is thus a function of the respective value of one or more than one operating parameter, which thus represents the state of the system or process.

In a controller, the actual state is influenced by changing one or more operating parameters (then also referred to as manipulated variables) of the system or process, e.g. by means of an actuator. In the case of regulation, the actual state is compared with the target state and the system or the process is influenced by means of a corresponding manipulated variable (using the actuator) in such a way that the deviation of the actual state from the target state is minimized. The actual state can be determined based on a measurement (e.g. using a measuring element) of one or more than one operating parameter (then also referred to as a controlled variable).

A sensor (also referred to as a detector) can be understood as a converter that is set up to detect a property of its environment that corresponds to the sensor type (e.g. qualitatively or quantitatively) as a measured variable, e.g. a physical property, a chemical property and/or a material Nature. The measured quantity is the physical quantity to which the measurement by means of the sensor applies. An example of a quantitatively recorded measured variable is a radiation power, for example, the actual state of which can be converted into a measured value by means of the sensor.

Each sensor can be part of a measurement chain that has a corresponding infrastructure (e.g. having a processor, storage medium and/or bus system and the like). The measuring chain can be set up to control the corresponding sensor (e.g. a photometric sensor), to process its detected measured variable as an input variable and based on this to provide an electrical signal (also referred to as a sensor signal) as an output variable which represents the detected input variable. Basically, the sensor signal can be an analog or digital sensor signal that represents the measured variable. For example, the output variable can indicate the measured value. The measurement chain can be implemented, for example, by means of a so-called control device.

According to various embodiments, a sensor can be set up to detect a photometric property (also referred to as a radiation property) of optical radiation as an input variable (then also referred to as a photometric sensor). Examples of the photometric property include: luminous flux (also referred to as radiant power), luminous intensity, illuminance (more graphically also referred to as radiant intensity or intensity for short), quantity of light and/or exposure. Among other things, reference is made here to the more easily understood radiation power or radiation intensity men. It can be understood that what has been described with regard to the radiation power or radiation intensity can apply by analogy to any other property of the optical radiation. The radiation intensity is a surface power density (eg in W/m ² ).

In this regard, reference is made herein to the term "level". The level designates a dimensionless quantity, which corresponds to the quantity of the measured quantity recorded as the input quantity or the quantity of the output quantity of the measuring section. The level can optionally be normalized, for example in such a way that its maximum is 1 (or 100%) and its minimum is 0 (or 0%). Reference is made herein to a normalization of the level at which the level increases as a substrate is transported into the beam path. Depending on the context, a level of 0% can then correspond, for example, to the upper limit of the value range that can be intrinsically scanned by the sensor and/or to a completely free beam path. A level of 100% can correspond, for example, to the lower limit of the value range that can be intrinsically scanned by the sensor, to the background noise, which is also detected when the optical radiation is switched off, or to a completely interrupted beam path. It can be understood that what has been described with regard to this normalization of the level can also apply by analogy to any other represented level.

According to various embodiments, reference is made to the transporting of one or more items to be transported (also referred to as transporting items), eg one or more than one substrate. Goods can be transported by means of a transport device. In order to transport the goods, the transport device can be arranged in a vacuum processing chamber (also referred to simply as a vacuum chamber), so that the goods can be transported in a vacuum. For this purpose, the environmental conditions (the process parameters) within the vacuum processing chamber (eg process pressure, temperature, gas composition, etc.) can be set or regulated during the transport of the goods. For example, a working gas and/or a gaseous coating material can be provided within the vacuum processing chamber. The vacuum processing chamber can, for example, be set up to be airtight, dust-tight and/or vacuum-tight, so that a gas atmosphere with a predefined composition (also referred to as working atmosphere) or a predefined pressure (also referred to as working pressure or process pressure) is provided within the vacuum processing chamber (e.g. according to a setpoint). The vacuum chamber can be set up in such a way that a vacuum (ie a pressure of less than 0.3 bar) and/or a pressure in a range from approximately 1 mbar to approximately 10 ^-3 mbar (in other words fine vacuum) or less is provided therein can, e.g. a pressure in a range from about 10 ^-3 mbar to about 10 ^-7 mbar (in other words high vacuum) or less can be provided, e.g. a pressure of less than high vacuum, e.g. less than about 10 ^-7 mbar (with other words, ultra-high vacuum) may be or may be provided. The lowest pressure that can be reached in the vacuum chamber is also referred to as the residual vacuum. By means of the coating material, the goods to be transported can be coated, for example.

The term "controller" can be understood as any type of logic-implementing entity, which can include, for example, a processor (and, for example, corresponding circuitry), which can, for example, execute software stored in a storage medium, in firmware, or in a combination thereof , and can issue instructions based on it. The controller (e.g. implementing a control loop) may be configured to implement one or more than one of the methods described herein. For this purpose, the control device can have the processor, which is set up to implement the respective method. For example, the processor can be set up to issue appropriate instructions for driving. Alternatively or additionally, the processor can be set up to receive and process corresponding instructions and signals. The instructions received by the processor can be implemented, for example, using code segments which are stored on a non-volatile data memory. For example, the code segments may include at least instructions that, when executed by the processor, cause the processor to perform one of the methods. The control device can have, for example, a programmable logic controller (PLC) or be formed from it.

According to various embodiments, a data store (also more commonly referred to as a storage medium) may be a non-volatile data store. The data memory can, for example, have or be formed from a hard disk and/or at least one semiconductor memory (such as, for example, read-only memory, random access memory and/or flash memory). The read only memory may be, for example, an erasable programmable read only memory (may also be referred to as an EPROM). The random access memory can be non-volatile random access memory (also known as NVRAM - "non-volatile random access memory”). For example, one or more of the following may be stored in the data store: the code segments, the reference, and the like.

The term "processor" can be understood as any type of entity that allows the processing of data or signals. For example, the data or signals may be treated according to at least one (i.e., one or more than one) specific function performed by the processor. A processor can be an analog circuit, a digital circuit, a mixed-signal circuit, a logic circuit, a microprocessor, a central processing unit (CPU), a graphics processing unit (GPU), a digital signal processor (DSP), a programmable gate array (FPGA), a comprise or be formed from an integrated circuit or any combination thereof. Any other way of implementing the respective functions, which are described in more detail below, can also be understood as a processor or logic circuit, for example virtual processors (or a virtual machine) or a large number of decentralized processors which are connected to one another, for example by means of a network, arbitrarily are spatially distributed and/or have any share in the implementation of the respective functions (e.g. distribution of the computing load among the processors). The same generally applies to differently implemented logic for implementing the respective functions. It will be appreciated that one or more of the method steps detailed herein may be performed (e.g., implemented) by a processor through one or more specific functions performed by the processor.

The term “actuator” (e.g. having an actuator or actuator) can be understood as a converter which is set up to influence a state, a process (e.g. a coating process) or a device in response to the activation of the actuator. The actuator can convert a control signal supplied to it (by means of which the control takes place) into mechanical movements or changes in physical variables such as pressure, electrical voltage or temperature. For example, an electromechanical actuator may be configured to convert electrical energy into mechanical energy (e.g., through motion) in response to being commanded. For example, an electrothermal actuator may be configured to convert electrical energy into thermal energy in response to being actuated. A purely electrical actuator can be set up, for example, to convert electrical energy into electrical energy of a different type (e.g. specific voltage, current, frequency and/or power) in response to the actuation.

An actuator can be set up to influence the actual state (also referred to as the actual operating point) of the transport of goods (e.g. its manipulated variable), which is operated (e.g. supplied and/or maintained) by means of the actuator. The influence can be direct or indirect.

For example, the actuator can change an electrical voltage as a manipulated variable, by means of which the transport of goods is supplied, so that the speed of the transport of goods is changed as a result. For example, the actuator can change a speed of a transport roller as a manipulated variable, so that as a result the speed of the crop transport and/or its clocking is changed. In analogy, distances between the goods to be transported, the spatial density of the goods to be transported or the like can be changed.

Examples of components of an actuator include: a power source (if present), a gearbox (if present), a motor, or the like. The voltage source can be set up, for example, to generate one or more than one voltage according to the activation and to supply it to the motor. The transmission can be set up, for example, to feed one or more than one torque of the motor to the crop transport.

According to various embodiments, the goods can be transported in a controlled and/or regulated manner. For this purpose, the transport device can be controlled based on a parameter. A parameter is referred to herein as a variable that can generally be a measured variable (e.g. is detected by sensors) or is determined (e.g. calculated) based on one or more than one measured variable.

In principle, the substrate can have or be formed from a metal, a ceramic (eg having an oxide, a nitride and/or a carbide) or an organic material. In particular, reference is made herein to substrates that are transmissive to the optical radiation (also referred to as optically transmissive), eg, translucent (eg, transparent or opaque). A light-transmitting substrate can, for example, comprise or be formed from glass (eg quartz glass or window glass), eg containing silicon (then also referred to as glass substrate). A transparent substrate can, for example, have a polymer or be formed from it (then also referred to as a glass substrate). For example, the glass substrate can be a glass pane. Herein an example is given on glass substrates or their optical detection (then also referred to as glass detection) reference, it being understood that what has been described for this can apply by analogy to any other substrate material.

1 10 illustrates a method 100 according to various embodiments in a schematic flow diagram. The method includes, in 11, comparing the transport of goods at a first point in time with the transport of goods at a second point in time. Based on this, a parameter of the transport of goods can be determined according to various embodiments.

Goods can be transported by means of a transport device. Goods transport can, for example, involve the transport of several (e.g. panel-shaped) goods to be transported, e.g. one after the other. The multiple items to be transported can have a first item to be transported and a second item to be transported, which are transported one behind the other.

The first item to be transported can have at least a first (e.g. plate-shaped) substrate and optionally a first (e.g. plate-shaped) substrate carrier, in which the first substrate is inserted. The second item to be transported can have at least a second (e.g. plate-shaped) substrate and optionally a second (e.g. plate-shaped) substrate carrier, in which the second substrate is inserted.

The parameter (also referred to as transport parameter) can represent, for example, a deviation in the transport of goods at the first point in time from the transport of goods at the second point in time (also referred to as transport deviation). Examples of the parameter will be explained in more detail later.

The method optionally includes, in 13, driving a transport device based on a result of the comparison, for example based on the parameter. The method optionally comprises, at 15, generating a message (e.g. according to a network communication protocol) based on a result of the comparing, e.g. based on the characteristic.

The message can, for example, contain information about the transport of goods and/or about the transport deviation. For example, the message can include a submission about a cause of the transportation discrepancy (also referred to as a transportation disruption). The cause can be determined on the basis of the parameter, for example.

The method 100 is explained below, inter alia, using the easier to understand transport device. It can be understood that the method 100 can be implemented by means of a controller or code segments, optionally also separately from the transport device, or can be applied to the transport device. Accordingly, the control device can have an interface to which the transport device (e.g. its interface) can be connected. Accordingly, the transport device can have an interface to which the control device can be connected.

Reference is also made here to the more easily understandable substrates as goods to be transported. However, it can be understood that what is described for the substrates can apply analogously to other transported goods, for example if the transported goods have several substrates transported as a group (also referred to as a batch or substrate batch).

Examples of comparing include: comparing two measurements with each other, comparing two sets of measurements with each other, comparing two measures (e.g., an integral and/or an average) each based on one or more than one measurement with each other. More generally speaking, the transport process recorded at or from the first point in time (e.g. one or more than one measured value representing this) can be mapped to a first parameter and the transport process recorded at or from the second point in time (e.g. one or more than one measured value representing this ) can be mapped onto a second parameter, the comparing comprising comparing the first parameter and the second parameter with one another. For example, the comparison can include comparing a first group of measured values, which represent the transport process recorded at or from the first point in time, with a second group of measured values, which represent the transport process recorded at or from the second point in time.

2 12 illustrates a transport arrangement 280 comprising the transport device 200 according to various embodiments in a schematic side view or cross-sectional view (facing the transport path). The transport device 200 can have a conveying device 201 (also referred to as a conveyor). The conveyor device 201 can be, for example, of the roller conveyor or belt conveyor type, but can also be of another conveyor type. The following is an easy-to-understand type of roller conveyor, where understood that what is described for the roller conveyor can apply by analogy to any other type of conveyor.

The roller conveyor 201 can have a plurality of rotatably mounted transport rollers 202 for transport in a direction 101 (also referred to as the transport direction 101). The goods can be transported along a transport path 111 or a transport surface 111, which is, for example, along the transport direction 101, and/or at a speed (also referred to as transport speed). The transport path 111 or the transport direction 101 (direction 101 of the transport of goods) can be transverse to an axis of rotation of one or more than one transport roller 202 . The transport path 111 can lie in the transport surface 111 which is parallel to one or more than one axis of rotation of the transport rollers 202 .

A plurality of goods to be transported 102 can be transported by means of the transport device 200 . Examples of the goods to be transported 102 have a plate-shaped substrate. For example, each plate-shaped substrate can be transported directly on the conveyor device 201, e.g. Examples of the goods to be transported 102 have a plate-shaped substrate carrier that is set up to carry one or more than one (plate-shaped or non-plate-shaped) substrate (for example if the substrates are small, bulky or sensitive).

The transport device 200 can also have a transport detection device 302 . The transport detection device is set up to detect the transport of goods by means of optical radiation 302s. The optical radiation 302s is emitted along a beam path through the transport surface 111 along a direction (also referred to as emission direction) that is oblique to the transport surface 111 .

Optical radiation (e.g. light) can be understood herein as radiation in the ultraviolet range (also referred to as the UV range), in the visible range or in the infrared range (also referred to as the IR range), e.g. in the near-infrared range. The UV range is the wavelength range from 100 nanometers (nm) to 400 nm. The visible range is the wavelength range from 400 nm to 780 nm. The infrared range is the wavelength range from 780 nm to 1 mm (millimeter). The near-infrared range is the wavelength range from 780 nm to 2500 nm. Light can, for example, have optical radiation in the near-infrared range, visible range and/or UV range. For easier understanding, reference is made herein to light as optical radiation, it being understood that what has been described for light can also apply to optical radiation of other wavelengths.

The emission direction can be transverse to the transport direction 101, for example. The emission direction can, for example, enclose a larger angle with the transport direction 101 than with the transport surface 111. The orientation of the emission direction will be explained in more detail later.

The transport device 200 can have, for example, one or more than one actuator 207 (also referred to as transport actuator 207), by means of which the goods are transported and/or which is coupled to one or more than one of the transport rollers 202.

The transport device 200 can optionally have a control device 205 which is set up to carry out the method 100 . The control device 205 can be coupled to the transport detection device 302, for example. The control device 205 can be coupled to one or more than one actuator of the transport device 200, for example. The plurality of transport rollers 202 can be coupled to the transport detection device 302, for example, along an interaction chain 281, which has the one or more than one transport actuator 207 and/or the control device 205.

By means of the transport actuator 207, mechanical power can be supplied to the crop transport, for example. A transport actuator 207 can be set up, for example, to supply torque to one or more than one transport roller 202, to generate the torque, to brake one or more than one transport roller, or the like. Examples of transport actuators include: a transmission, a drive train, an electromechanical transducer (e.g., a motor), a power supply, a speed controller, and the like.

The or each transport actuator can be set up to change the operating point of the transport device 200 or to change the operating point of the crop transport.

Examples of operating parameters of the transport device, which can be changed by means of a transport actuator, include: an electrical power consumed by the transport device, a speed and/or a transmission ratio of the transmission; a speed and/or a torque which is generated by means of the electromechanical converter, an electrical power provided by the energy supply, a speed of one or more than one transport roller, a speed difference between two transport rollers and the like.

Examples of operating parameters of the transport of goods, which can be changed by means of a transport actuator, include: a first transport speed of the first transport item; a second transport speed of the second transport item; a difference between the first transport speed and the second transport speed, a time dependency of the first transport speed, a time dependency of the second transport speed, a transport direction, an acceleration of the first transport item and/or the second transport item, a deceleration of the first transport item and/or the second transport item .

3 12 illustrates the transport arrangement 280 according to various embodiments in a schematic side view or cross-sectional view 300 (viewed from the transport direction 101). The transport detection device 302 can have an emitter for emitting the optical radiation in the emission direction 302r.

An angle 302w (also referred to as the emission angle) can be spanned between the emission direction 302r and the transport surface 111 . The emission angle 302w can have a first leg, which extends along the emission direction 302r, and a second leg, which lies in the transport surface 111 or is parallel to an axis of rotation 202r of the transport roller(s) 202. The emission angle 302w may be less than about 45°, e.g., about 23°, e.g., about 12°, e.g., about 10°, e.g., about 5°. The smaller the emission angle 302w, the more reliable the detection of the transport of the goods and the better the sensor signal can be.

The transport detection device 302 can basically have at least two optical elements 312, 314, which are set up to exchange the optical radiation with one another, are arranged on opposite sides of the transport surface 111, and are optically coupled to one another along a linear path in the emission direction 302r. The two optical elements 312, 314 can, for example, be at a distance from one another which is greater than an extension of the transport roller(s) 202 along its axis of rotation. This improves the construction.

The two optical elements 312, 314 can thus be part of an interaction chain along which the optical radiation 302s is exchanged. The two optical members 312, 314 are illustratively set up to provide a path (also referred to as a beam path) along which the optical radiation is exchanged, the beam path intersecting the transport surface along the emission direction 302r. Optionally, the beam path can be deflected once or more than once, e.g. in such a way that the sensor (also referred to as transport sensor) and radiation source (the place where the optical radiation is generated) are placed as favorably as possible. The more frequently the beam path is deflected, the more error-prone the transport detection device 302 can be, but the more favorably the transport sensor and radiation source can be placed.

In a first exemplary implementation of the transport detection device 302, a first optical member 312 may include the emitter and a second optical member 314 may include a transport sensor configured to detect the optical radiation emitted from the emitter in the emission direction towards the transport sensor. This further simplifies the construction.

In a second example implementation of the transport detection device 302, the first optical member 312 may include the emitter and the transport sensor, and the second optical member 314 may include a reflector (e.g., comprising a mirror) configured to redirect the optical radiation from the emitter to the transport sensor (e.g. to reflect). This increases the distance of the beam path and thus the signal quality.

In a third exemplary implementation of the transport detection device 302, the emitter can be a radiation source which is set up to generate the optical radiation and to emit it directly in the emission direction 302r. The radiation source can have an electro-optical converter, for example. The electro-optical converter can be set up to convert electrical power into optical power and to emit the optical power by means of the optical radiation. The radiation source can optionally have a beam shaping unit that is set up to bundle the optical radiation into a beam (e.g. a laser beam). The beam shaping unit can have, for example, one or more than one lens and/or one or more than one non-planar mirror.

In a fourth example implementation of the transport detection device 302, the emitter may include a reflector (e.g., comprising a mirror) onto which the radiation source is directed.

Examples of the radiation source include: an optoelectronic radiation source, an electrothermal radiation source (eg, a gas discharge lamp or an incandescent lamp), or a resonator radiation source (eg, a laser). Examples of the optoelectronic radiation source include: a (eg organic or inorganic) light-emitting diode (also referred to as an LED) and/or a laser diode. Accordingly, the optical radiation can have, for example, a laser beam or be formed from it.

The transport sensor can be set up (e.g. arranged and/or aligned) in such a way that it is in the beam path. For example, the transport sensor can be set up in such a way that the optical radiation or at least its reflection falls onto the transport sensor essentially along or from the emission direction 302r.

The transport sensor can be set up to output a sensor signal which represents the detected optical radiation, e.g. its power (also referred to as radiation power).

Various aspects according to various exemplary embodiments are explained below.

Goods transport can be recorded using a Keyence laser sensor as a transport sensor. A laser beam 302s with a rectangular profile can be used for glass detection. The rectangular beam profile facilitates glass detection compared to a point beam profile. The reason lies in the possibility of monitoring the entire transport width with a suitable beam alignment. As shown, the laser beam 302s is set at a slight angle relative to the transport surface 111.

The laser beam 302s can be aligned in such a way that on the right-hand side the top edge of the laser beam strikes the bottom edge of the glass substrate. The conditions on the left-hand side can be correspondingly reversed. There the lower edge of the laser beam touches the upper edge of the glass substrate. This special alignment of the beam path maximizes the switching hysteresis in contrast to a horizontal alignment of the laser beam. If no glass substrate is arranged in the beam path, almost 100% of the emitted light is detected by the transport sensor (e.g. its reflection) and a correspondingly low level is output (e.g. close to 0%). If a glass substrate is arranged in the beam path, less, e.g. essentially no light, can fall onto the laser sensor as a transport sensor (e.g. be reflected back) and the level is correspondingly high (e.g. close to 100%). In the most favorable case, there is a switching hysteresis of 100%. In contrast, with a 2 mm (millimeter) thick glass substrate and a 8 mm high beam (also known as beam height) in horizontal alignment, there would only be a hysteresis of 25% (2 mm/8 mm). With a beam height of 12 mm, the hysteresis value would be even less favorable at approx. 16%. This basic behavior also applies to a substrate batch. Here, too, the inclination of the laser beam provided according to various embodiments relative to the transport surface 111 leads to a maximization of the switching hysteresis.

wobei α den Emissionswinkel 302w bezeichnet, h die Substratdicke (d.h. dessen Ausdehnung in Richtung 105 quer zur Transportfläche 111) bezeichnet und b die Substratbreite (d.h. dessen Ausdehnung in Richtung 103 quer zur Transportrichtung) bezeichnet.Mathematically, this can be described as detecting a thick appearing substrate, ie a substrate with apparent thickness (also referred to as apparent substrate thickness). The apparent thickness can be expressed as: $${\text{i.e}}_{\text{s}}=\text{H}\cdot \text{cos}\left(\mathrm{a}\right)+\text{b}\cdot \text{sin}\left(\mathrm{a}\right)$$

where α designates the emission angle 302w, h designates the substrate thickness (ie its extent in direction 105 transverse to the transport surface 111) and b designates the substrate width (ie its extent in direction 103 transverse to the transport direction).

With an approx. 4 m (meter) wide system and a laser beam height of 12 mm, an angle of 0.34° results for α. With a glass thickness of h = 2 mm, the value h cos(α) is 1.99 mm. While b·sin(α) at b = 4 m results in a value of 23.7 mm. This clearly shows the effectiveness of the tilting. A glass substrate can be detected horizontally essentially unimpaired (1.99 mm ≈ 2 mm). Furthermore, since the apparent substrate thickness (e.g. glass thickness) increases by 10 times (1.99 mm + 23.7 mm compared to 2 mm), the reliability of detection increases. Even if the glass substrate is only 3 m wide, with this setting you still get twice as much compared to a beam path running parallel to the transport surface 111 (e.g. horizontal).

As a result, the sensor signal also represents the virtual substrate thickness, which includes the substrate width b (e.g. glass width). As the above calculation shows, the substrate width b provides the dominant signal component. It can thus be determined based on the sensor signal, e.g. on the signal level, whether the substrate is complete, whether the substrate is damaged and/or whether parts of the substrate are missing. In the case of a damaged or incomplete substrate (e.g. broken pane), the signal strength changes by the corresponding missing area.

According to various embodiments, the transport detection device 302 can turn on be directed to implement a signal level output. For this purpose and/or for direct substrate detection, the transport detection device 302 can have its own evaluation circuit. A transport detection device 302 set up in this way (eg with special hardware for the evaluation circuit) can be faster and/or more reliable.

Alternatively or additionally, the transport sensor can be set up to detect a beam profile which, for example, represents at least one line or one area in the beam cross section. According to various embodiments, the radiation source can be set up to provide a linear or planar beam cross section. The beam path can be aligned in such a way that the linear beam cross-section is oriented transversely to the transport direction.

The transport device 202 can be arranged in a vacuum chamber 802 . Optionally, the or each substrate can be coated in the vacuum chamber 802 or in a vacuum, for example by means of a vapor deposition.

Various implementations of the method 100 are explained below.

4A until 4C each illustrate different diagrams 400a to 400c, in which a level 501 is plotted against time 503, according to various embodiments of the method 100. The plotted level 501 can, for example, represent the deflection of an analog sensor signal, represent the decoded digital sensor signal, or the radiant power of the represent optical radiation detected by the sensor. Basically, the sensor signal can be an analog or digital sensor signal, which represents a photometric property (also referred to as a radiation property) of the optical radiation detected by the sensor.

The peak-valley value (corresponds, for example, to the amplitude) can be understood here as a deflection in a very general manner.

Diagram 400a illustrates the time-dependent level profile in a time interval [t=0, t=15], in which a substrate has been transported past the transport detection device. The time interval can be in arbitrary units or in seconds, for example.

Each level maximum 401 represents that a substrate is arranged in the beam path of the transport detection device or that the beam path of the transport detection device is interrupted by a substrate. Each level minimum 403 represents that no substrate is arranged in the beam path of the transport detection device or the beam path of the transport detection device is free.

The deflection A of the level profile clearly represents the geometric extent (eg substrate thickness and/or substrate width) of the substrate. The width ΔT of the level minimum 403 represents the distance between two substrates transported directly one after the other (also referred to as the substrate distance or substrate gap). The width T _B of the level maximum 401 (also referred to as duration) represents the length of the substrate (also referred to as substrate length) and/or its speed. These variables of the level curve are referred to in more detail below, it being understood that what has been described in this regard can also apply to other variables of the level curve, e.g. a first frequency f=1/T _B of the level curve, a second frequency f=1/ΔT des Level curve, the duty cycle T _B / ΔT, a ripple of the level curve and the like.

A first level maximum 401 can thus represent the first transport item and a second level maximum 401 the second transport item. The two level maxima can, but do not necessarily have to, be in immediate succession.

Diagram 400b illustrates a number of time-dependent level curves P _n superimposed on one another for n=1 to n=5, which represent a number of substrates transported one after the other. The level maximum 401 of the nth level curve P _n can represent the nth substrate which was detected at the time t _n . The nth level profile P _n can correspond to an nth time interval [t=t _n -4, t=t _n +11], in which the nth substrate has been transported past the transport detection device, this being shown in diagram 400b are projected into the time interval [t=0, t=15].

The nth point in time t _n is the point in time when the transport or the transport process was recorded. Detecting the nth substrate may include detecting it for a duration T _B =[t _n , t _n +T _B ].

The nth level profile P _n can have an nth deflection An, which corresponds to the nth substrate. Depending on the situation, the time difference t _n -t _n-1 (also referred to as the acquisition cycle) can be in the range of hours, days or weeks.

As shown, for example, the deflection can be due to a change in time (also known as amplitude drift or referred to as first level drift).

In analogy, the nth substrate can have an nth substrate distance ΔT _n from the substrate transported directly in front of it. For example, the substrate distance ΔT _n can be subject to a change over time (also referred to as distance drift or second level drift).

Alternatively or additionally, several transport detection devices can be used, which are arranged one behind the other along the transport path 111 . This makes it possible, for each of the multiple transport detection devices, to determine the point in time at which the change in level (e.g. the nth level maximum, a level disturbance and/or the nth level minimum) is detected by means of the transport detection device. Based on the points in time or on their time interval from one another, the time required for a substrate to cover the distance between the multiple transport detection devices (also referred to as transit time) can be determined. In analogy to the first level drift, the propagation time can be subject to a change over time (also referred to as propagation time drift or third level drift).

Reference is made herein to level drift more generally. It can be understood that what has been described for the level drift can apply by analogy to the first level drift, the second level drift, the third level drift, an interference drift, a jitter drift or any other change in the level profile over time.

Diagram 400c illustrates the determined time-dependent deflection An for n=1 to n=5.

According to various embodiments, the level (e.g. level of the sensor signal) is taken into account when determining the parameter, e.g. its amplitude. In contrast to the evaluation of the purely binary occupied/not occupied signal, this offers more information on the basis of which the transport can be controlled and/or regulated in a significantly more stable or more reliable manner. Examples of such information for determining the parameter are explained below.

In a first exemplary implementation of the method 100, the level drift is determined as a parameter (e.g. the amplitude drift or a time drift of the signal deflection A), for example based on a single transport sensor at the same operating point of the transport device. Depending on the acquisition cycle (e.g. hours, days, weeks), a reversible level drift can be determined, which occurs, for example, due to thermal expansion or other temperature-dependent effects in the transport area. A signal correction can be carried out based on the reversible level drift, which improves the stability of the transport of goods.

An irreversible level drift (e.g. over a long period of time) can be caused by contamination (e.g. the transport detection device, the signal path and/or the transport device), for example. For example, the contamination can lead to characteristic features of the level drift, on the basis of which the contamination can be determined as the cause, which can be passed on to a maintenance service by means of a message. Contamination can lead to a similar level drift at different points of the transport path 111, for example.

A level drift that is periodically repeated without further intervention can be caused, for example, by deformations or damage to the transport device. In the event of a reversible level drift, this should behave similarly at all recorded points on the transport surface or at all transport sensors. Deformations and damage, on the other hand, should only show up at individual points on the transport surface 111 or transport sensors. In other words, as an alternative or in addition to determining the level drift as a parameter, a comparison (e.g. correlation) of the level drift of transport sensors that are different from one another can take place, with a result of the comparison being able to be used as a parameter.

In a second exemplary implementation of the method 100, a first level is determined using a first transport detection device and a second level is determined using a second transport detection device, with the result of comparing the first level with the second level (e.g. their level drift) being used as a parameter. The first transport detection device can be at a distance along the transport path 111 from the second transport detection device, for example.

In a third exemplary implementation of the method 100, the propagation time drift is determined as a parameter (eg a time drift of the substrate distance), for example with the same operating point of the transport device or the same nominal transport speed between (eg directly) adjacent transport detection devices. Without a transport disruption, the running time (eg of a gap in the substrate) between two adjacent sensors can be constant over time. A running time drift can occur if the transport rollers are coated by a coating process, so that their circumference increases. The increasing circumference increases the real substrate speed at a constant rotational speed of the transport rollers.

By controlling the transport device based on the runtime drift as a parameter, the transport of goods can be set up more reliably, since the runtime drift can be used when calculating the speed of individual transport rollers or the speed can be adjusted. For example, a constant material transport speed means that the coating quality of the substrates can be kept constant. For example, the message can include a request for maintenance of the transport device.

5A until 5C each illustrate different diagrams 500a to 500c, in which the level 501 over time 503 or a jitter 505 over n for the times t _n is plotted, according to different embodiments of the method 100.

Diagram 500a again illustrates a plurality of time-dependent level curves P _n superimposed on one another for n=1 to n=5, which represent a plurality of substrates transported one after the other. In the case of clocked sampling of the photometric property, a variation in the propagation time (also referred to as jitter) can occur. The sampling times 551 are highlighted.

Diagram 500b illustrates the change in jitter over time (also referred to as jitter drift), here plotted against n.

Diagram 500c illustrates a time-dependent level course which has a level disturbance 515 (e.g. a plateau ripple) due to a substrate batch or due to a damaged substrate. The level disturbance 515 can be determined by comparing two or more level maxima with one another. For example, the level disturbance 515 can represent a deviation of the two or more level maxima from one another.

The two or more level maxima can, for example, correspond to substrates that are different from one another, e.g. detected by means of the same transport detection device. The disturbance drift can then represent, for example, that the transported goods have a damaged substrate.

The two or more level maxima can, for example, correspond to the same substrate, e.g. detected one after the other by means of different transport detection devices. The disturbance drift can then represent, for example, that a substrate was damaged during transport.

In analogy to the level drift, the level disturbance 515 can also be subject to a change over time (also referred to as disturbance drift).

In a fourth exemplary implementation of the method 100, the jitter is determined as a parameter. Based on the jitter, for example, the substrate position can be determined and, based on this, the transport by means of the transport device can be controlled and/or regulated. For example, the transport device can be controlled in such a way that the substrate gaps are minimized. As an alternative or in addition, the transport device can be controlled in such a way that a collision of substrates (also referred to as driving onto one another) is inhibited.

In a fifth exemplary implementation of the method 100, the jitter drift is determined as a parameter.

In a sixth exemplary implementation of the method 100, the level profile of different time intervals is compared with one another and a result of the comparison is used as a parameter. For example, the level curve from sensor to sensor when passing through a substrate can be recorded and compared with each other. The course of the level during the passage through the substrate can essentially correspond to a square-wave function without disturbing the substrate. Its level maximum 401 has a deflection A and the duration T _B (also referred to as the acquisition duration). If the duration T _B for a level condition changes suddenly from one sensor to the next sensor, a change in the substrate sequence can be determined as a transport disturbance, for example. The transport disruption can include, for example, that two substrates have collided. The transport disruption can have, for example, that a larger gap in the substrate has formed, for example when a substrate is broken. This can even be applied to a substrate batch.

In a seventh exemplary implementation of the method 100, the result of a convolution of the level curves at the individual sensors is determined as a parameter. The result of the convolution can indicate, for example, whether there have been any shifts within the batch or whether the batch is still complete.

In an eighth exemplary implementation of the method 100, the distance drift can be determined as a parameter. For example, several substrate distances ΔT _n can be compared with one another. The distance drift can, for example, give an indication of an impending substrate jam as a transport disruption. more general in other words, the transportation disruption can be predicted (also referred to as predicted) based on the parameter. It would be expected that in the immediate run-up to a substrate jam, certain events (eg with shorter pauses), eg the occurrence of a distance drift, follow one another. By correlating these events, coincidences can be determined, with which a congestion forecast can be made at an early stage. Based on this, the transport device can be controlled, for example by inserting an artificial transport pause.

In a ninth exemplary implementation of the method 100, the level drift is compared to one or more than one reference and the transport device is controlled based on the comparison. Each reference can be assigned to a transport disturbance, for example, so that the transport disturbance assigned to the reference can be determined if the level drift matches the reference. As an alternative or in addition, pattern recognition can be applied to the level curve, with the recognized pattern of the level curve being compared with the reference.

In a tenth exemplary implementation of the method 100, a correlation evaluation between substrate gaps and substrate jams is carried out over a longer period of time, which reflects the gap behavior at the substrate jams.

In a tenth exemplary implementation of the method 100, the sensor signal is continuously sampled (e.g., such that one or more readings are obtained). Each measured value represents the transport process at a point in time when the transport process was recorded. The comparison shows that the measured values of a first period (e.g. the length of time substrate length/speed) are compared with the measured values of a second period. The digital scanning of the signal curve can be triggered in each case on a rising signal edge of a certain height as an indicator of the beginning of a substrate and the falling edge of a certain size as an indicator of the end of a substrate (illustratively a type of digital oscillograph).

A plurality of measured values can be used, for example, to determine waviness.

Various examples are described below, which relate to those described above and shown in the figures.

Example 1 is a method for a transport process, comprising the method: comparing the transport process recorded at or after a first point in time (e.g. for a first period of time) (or a first measured variable representing it) with that at or after a second point in time (e.g. for a second time period and/or after the first time period) recorded transport process (or a second measured variable representing this); the method further comprising: controlling a transport device, by means of which the transport process is carried out, based on a result of the comparison; and/or generating a message (e.g. based on a result of the comparing), the message comprising an indication (e.g. based on the result of the comparing) about the transport process.

Example 2 is a method for a transport device, by means of which one or more than one (e.g. plate-shaped and/or optically transparent) item to be transported is transported, the method comprising: comparing the transport recorded at or from a first point in time (or a first measured variable) with the transport recorded at or from a second point in time (or a second measured variable representing this); the method further comprising: controlling a transport device, by means of which the transport takes place, based on a result of the comparison; and/or generating a message (e.g. based on a result of the comparing), the message comprising an indication (e.g. based on the result of the comparing) about the transport process.

Example 3 is the method according to example 1 or 2, wherein the result of the comparison shows a deviation of the transporting or transporting process detected at or from the first point in time from the transporting or transporting process detected at or from the second point in time.

Example 4 is the method according to any of Examples 1 to 3, further comprising: determining a cause for the deviation, the indication of the transport or the transport process having the cause.

Example 5 is the method according to any one of Examples 1 to 4, wherein the transport process comprises transporting one or more than one (e.g. plate-shaped and/or optically transparent) item to be transported, e.g. by means of the transport device.

Example 6 is the method according to any one of examples 1 to 5, wherein the message is addressed to a maintenance service (e.g. its server and/or its mailbox) and/or generated according to a network communication protocol.

Example 7 is the method according to any one of examples 1 to 6, wherein the comparing comprises the transport process recorded at or from the first point in time for a first duration (eg the measurement data recorded over the first period) with the at or from a second point in time for to compare a transport process recorded over a second period (eg the measurement data recorded over the second period), a distance between the first point in time and the second point in time being greater than the first period and/or the second period (eg their sum).

Example 8 is the method according to any one of Examples 1 to 7, wherein the conveyance process detected at or from the first point in time comprises that a first plate-shaped conveyance is conveyed at a first location of the conveyance device; and wherein the transport process detected at or from the second point in time comprises that: the first plate-shaped transport good is transported at a second point of the transport device, and/or that a second plate-shaped transport good is transported at the first point of the transport device; wherein, for example, the first point and the second point are at a distance from one another that is greater than one (or, for example, twice, ten times or a hundred times) the extent of the first item to be transported along a direction of transport of the item to be transported. For example, any distance greater than sample time times velocity may be acceptable. This means that the rear edge of a first disk can be distinguished from the front edge of a second disk and it can be recognized that certain transport rollers can be controlled independently of each other (e.g. when braking or accelerating) (apparently a gap detection).

Example 9 is the method according to one of Examples 1 to 8, the result of the comparison having a parameter (e.g. of the transport process), with the transport device being controlled based on the parameter (e.g. as a controlled variable), for example.

Example 10 is the method according to any one of Examples 1 to 9, wherein the one or more cargo comprises a first cargo and/or a second cargo.

Example 11 is the method according to example 10, wherein the transport or transport process recorded at or from the first point in time has that the transport of the first item to be transported takes place at a first point (e.g. the transport surface and/or the transport device) and/or is detected by means of a first sensor, wherein the transport or transport process detected at or from the second point in time has that the transport of the first item to be transported takes place at a second location (e.g. the transport surface and/or the transport device) and/or by means of a second sensor is detected.

Example 12 is the method according to example 10, wherein the transport or transport process recorded at or from the first point in time has that the transport of the first item to be transported takes place at a first point (e.g. the transport surface and/or the transport device) and/or is detected by a first sensor, wherein the / the detected at or from the second point in time transport or transport process has that the transport of the second item to be transported takes place at the first point and / or is detected by a first sensor.

Example 13 is the method according to any one of Examples 1 to 12, wherein the or each load (e.g. the first and/or the second load) is respectively: transported sequentially; comprising or formed from a substrate; has a substrate carrier and one or more than one substrate placed therein.

Example 14 is the method according to one of Examples 1 to 13, wherein the first point in time and the second point in time are at a distance from one another that is greater than a quotient of an extent of the or each item to be transported (e.g. along a direction of transport or a transport direction ) and a speed of transport or transport speed (e.g. in meters per second); e.g. is greater than twice (ten times or a hundred times) the quotient. This clearly reflects the fact that comparisons are made over a longer period of time or over longer distances.

Example 15 is the method according to any one of Examples 1 to 14, wherein the comparing comprises comparing one or more metrics representing the transport process captured at or from the first point in time with one or more metrics representing the or represented by the transport process recorded from the second point in time.

Example 16 is the method according to one of examples 1 to 15, wherein the comparison is based on at least one sensor signal which represents the detected transport or the detected transport process.

Example 17 is the method according to example 16, wherein the at least one sensor signal comprises a first sensor signal representing the transport or transport process(es) detected at or from the first point in time; where that at least one sensor signal has a second sensor signal, which represents the transport or the transport process detected at or after the second point in time.

Example 18 is the method of example 16 or 17, wherein the comparing is based on a property of the at least one sensor signal, e.g., its change from the first time to the second time; wherein the comparing comprises, for example, comparing the property of the first sensor signal to the property of the second sensor signal.

Example 19 is the method of any of Examples 16-18, wherein the characteristic of the at least one sensor signal includes one or more of: a level of the respective sensor signal; a repetition pattern of the respective sensor signal; a deflection of the respective sensor signal; a phase of the respective sensor signal; a frequency of the respective sensor signal; a duty cycle of the respective sensor signal; a jitter of the respective sensor signal; a transit time of the respective sensor signal; and/or a plateau ripple of the respective sensor signal.

Example 20 is a control device configured to perform the method according to any one of Examples 1 to 19.

Example 21 is a non-volatile storage medium comprising code segments configured, when executed by a processor, to cause the processor to perform the method of any of Examples 1-19.

Example 22 is a transport arrangement comprising: a transport device (e.g. the transport device according to one of Examples 1 to 19) for transporting a (e.g. plate-shaped and/or permeable) item to be transported along a transport surface, a transport detection device (e.g. having a light barrier) for detecting the transport by means of optical radiation (e.g. light) emitted through the transport surface along a direction oblique to the transport surface; optionally the control device according to example 20.

Example 23 is the transport arrangement according to example 22, with the transport of the goods to be transported taking place along a transport direction which is transverse to the direction.

Example 24 is the transport arrangement according to example 22 or 23, wherein the transport device has a plurality of transport rollers, each transport roller being rotatably mounted with respect to an axis of rotation which is parallel to the transport surface.

Example 25 is the transport arrangement according to either of Examples 22 or 24, wherein the transport detection device comprises an emitter (e.g. optoelectronic) for emitting the optical radiation in the direction.

Example 26 is the transport arrangement according to one of Examples 22 or 25, wherein the transport detection device comprises a (e.g. optoelectronic) sensor for detecting the optical radiation (e.g. in or out of direction or at least its reflection), e.g. after it has been emitted through the transport surface .

Example 27 is the transport arrangement according to one of examples 22 or 26, wherein the direction with the transport surface encloses an (e.g. acute) angle, the angle being, for example, less than about 12°, e.g. than about 10°, e.g. than about 5°, e.g. as about 1°.

Claims (13)

Method (100) for a transport process, the method (100) comprising: • comparing (11) the transport process recorded at or from a first point in time with the transport process recorded at or from a second point in time; and • Controlling (13) a transport device (200) by means of which the transport process is carried out, based on a result of the comparison. Method (100) according to claim 1 , wherein the result of the comparison shows a deviation of the transport process recorded at or from the first point in time from the transport process recorded at or from the second point in time. Method (100) according to claim 1 or 2 , wherein the transport process recorded at or from the first point in time has that a first panel-shaped item to be transported is transported at a first point of the transport device. Method (100) according to claim 3 , wherein the transport process recorded at or after the second point in time has that the first panel-shaped item to be transported is transported at a second location of the transport device. Method (100) according to claim 3 , wherein the transport process detected at or from the second point in time comprises that a second flat shaped cargo is transported at the first point of the transport device. Method (100) according to any one of claims 3 until 5 , wherein the first point in time and the second point in time have a distance from one another that is greater than a quotient of: • an extension of the first item to be transported along a transport direction of the transport process; • and a transport speed of the transport process. Method (100) according to any one of Claims 1 until 6 , • wherein the comparison is based on a first sensor signal, which represents the transport process detected at or from the first point in time; • wherein the comparison is based on a second sensor signal, which represents the transport process recorded at or from the second point in time. Method (100) according to claim 7 , wherein the comparing comprises comparing a characteristic of the first sensor signal to a characteristic of the second sensor signal, the characteristic comprising one or more of: • a displacement of the respective sensor signal; • a jitter of the respective sensor signal; • a transit time of the respective sensor signal; • a plateau ripple of the respective sensor signal. Method (100) according to any one of Claims 1 until 8th , wherein the comparing comprises comparing one or more measured values representing the transport process recorded at or from the first point in time with one or more measured values representing the transport process recorded at or from the second point in time. Method (100) for a transport process, the method (100) comprising: • comparing (101) the transport process recorded at or from a first point in time with the transport process recorded at or from a second point in time; and • Generating (15) a message based on a result of the comparison, the message having an indication of the transport process. Control device (205), which is set up to carry out the method (100) according to one of Claims 1 until 10 . non-volatile storage medium comprising code segments which, when executed by a processor, are arranged to carry out the method (100) according to any one of Claims 1 until 10 bring to. Transport arrangement (280), comprising: • a transport device (200) for transporting a transport item (102) along a transport surface (111), • a transport detection device (302) for detecting the transport by means of optical radiation (302s) which is emitted through the transport surface (111) along a direction (302r) which is oblique to the transport surface (111).

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