DE102015107667A1 - metering - Google Patents

Abstract

The invention relates to a metering device for automated metering of a fluid medium, comprising a valve module with a connection for a media reservoir and a valve opening and a first camera which is coupled to the valve module. The metering device is characterized by a second camera which is attached to the valve module.

Description

The present invention relates to a metering device for automated metering of a fluid medium, comprising a valve module with a connection for a media reservoir and a valve opening and a first camera which is attached to the valve module.

Metering devices are basically known and are used for example for applying media to products such. B. electronic components. Accordingly, metering devices z. B. used in the production of mobile phones, in particular to meter liquid adhesives, coatings and the like on components.

Usually, the medium, which may have different viscosity, is pressurized in the media reservoir and metered with the aid of a valve of the valve module usually in drop form.

A position of the metered medium on the component can be detected by the first camera to the correct order z. B. the adhesive to check. In known metering devices, the metering device must be moved so that the camera is located above the component with the applied medium. Such movements of the dosing take time and slow down the production process of the components.

It is the object underlying the invention to provide a metering device which enables a faster production process and at the same time improves the quality of the production process.

This object is solved by the subject matters of the independent claims.

In particular, the object is achieved by a metering device comprising a second camera which is attached to the valve module. Due to the second camera, there are additional possibilities to move the metering device so that one of the cameras is located above a component to which the medium has been metered. A correct positioning of the metered medium can be determined in this way in less time, whereby a production process can be accelerated.

In addition, the second camera makes it possible to capture a component or a slide without a component first with the first camera without metered medium. Subsequently, the same component or the same location of the slide with metered medium can be recorded with the second camera. In this way, the dosing process can be better monitored, whereby a quality of the production process can be increased.

Advantageous embodiments of the invention are described in the description, the drawings and the dependent claims.

According to a first advantageous embodiment, the first and the second camera are mounted on two, in particular opposite, sides of the valve module to the valve module. For example, the cameras can be mounted directly on the valve module, whereby the first and the second camera can be moved together with the valve module. Preferably, small cameras will be used, the z. B. each have smaller dimensions than the valve module. In this way, a compact metering device can be created, which allows production processes in a small space.

Particularly preferably, the first camera, the second camera and the valve opening are arranged along a straight line. When metering the medium on different components or on different locations of the slide, the valve module can be moved along with the cameras along the straight line. In this way, the cameras can then stand exactly vertically above the respectively metered medium, whereby a particularly accurate detection of the metered medium is made possible. In particular, the valve opening is arranged between the first and the second camera as seen along the straight line. This makes it possible, in the process along the straight line z. Example, with the first camera to capture an image of the component without metered medium and to capture the component with metered (i.e., applied) medium with the second camera.

Preferably, the distance between the valve opening and the first and the second camera respectively corresponds to the distance between two components on the slide. The components on the slide can therefore be arranged in the same grid as the first camera, the second camera and the valve opening. It is advantageous that the inclusion of a first component without medium, the metering of medium to a second component and the detection of a third component with medium are simultaneously possible. The activation of the cameras can, for example, be triggered ("triggered") by the metering process of the valve module. Optionally, the camera images are recorded with a short delay after dosing. Due to the almost simultaneous execution of the image acquisition and the metering process, a significant increase in the operating speed of the metering device can be achieved because additional Movements can be omitted, which are usually necessary to move the camera over a component.

If the components are arranged in the manner of a matrix on the slide, then the metering device can be moved in a meandering manner over the slide, wherein the components can be provided with medium on the slide line by line. At the end of a line, the metering device can be moved such that only one camera is located above a component, whereas the valve opening and the second camera are located above no component. After such a position, the metering device can change to the next line, wherein the next line of components in a (in comparison to the previous line) reverse order is provided with medium.

According to a further advantageous embodiment, the dosing device comprises a third camera, which is mounted in particular on the valve module. The third camera may be mounted directly on the valve module, for example on a front side of the valve module. The first and second camera can be arranged in particular on side surfaces of the valve module.

The third camera allows faster movement of the metering device in the direction defined by the valve port and the third camera. Particularly when using components arranged like a matrix, it is possible to accelerate an advancement of the metering device into a new line since components can already be accommodated in the new line with the third camera. For this purpose, the third camera may be arranged so that a distance between the valve opening and the third camera corresponds to a distance or a multiple of the distance of the components on the slide.

Furthermore, the metering device may also include a fourth camera, which is arranged opposite to the valve opening of the third camera. By the fourth camera, according to the third camera also an acceleration of the movements of the metering device is possible.

Alternatively, the fourth camera is not disposed opposite to the third camera with respect to the valve opening. In this embodiment, the fourth camera includes a mirror that causes a field of view of the fourth camera with respect to the valve opening to face a field of view of the third camera.

Preferably, the lenses of the cameras lie in one plane. The viewing direction of the cameras may be perpendicular to the plane, wherein the plane is in particular aligned coplanar with a plane formed by the slide. The fields of view of the cameras can be adapted in particular to the size of the components and / or to the surface occupied by the metered medium.

According to a further advantageous embodiment, an actuator is provided with which the metering device, in particular in a plane, is movable. The actuator may generally be a robot or, for example, an XY table. Also, the metering device can only be moved linearly, wherein the straight line defined by the first camera, the second camera and the valve opening is parallel to the linear direction of movement.

Alternatively, the metering device can also be arranged stationary, wherein the components can be moved by means of the slide relative to the metering device.

Another object of the invention is a metering device for automated dosing of a fluid medium on an object, comprising a valve module with a connection for a media reservoir and a valve port, at least a first camera which is attached to the valve module, and at least one coupled to the first camera and with respect to the first camera fixedly arranged illuminant, which is designed to illuminate the object. The dosing device according to the invention comprises an arithmetic unit, which is designed to determine a height of the medium metered onto the object on the basis of a reflection of radiation of the at least one luminous means.

In other words, an image of the object is detected with the first camera, which shows a reflection of the illuminant on the metered medium. The arithmetic unit can then determine, for example on the basis of a known distance of the light source and / or the known spatial arrangement of the light source relative to the camera from the reflection of the light source, the height of the medium metered onto the object. The medium metered onto the object can be, for example, a circular metering point or a metering line.

Under the object is any surface to understand, to which the medium is applied by means of the valve module. For example, the object may be a component located on a slide.

The height of the metered medium is to be understood as meaning a maximum vertical distance between a boundary of the metered medium and the object or the component covered with the medium.

Particularly preferably, the arithmetic unit is designed to calculate a volume of the medium metered onto the object on the basis of the determined height. Depending on the particular medium used (eg adhesive, oil, paint, etc.), different geometric shapes of the medium may form on the object after dispensing. For example, the medium seen in cross-section may have the shape of a semicircle or a circle segment. Based on the height of the circle segment can then be closed to the volume of the metered medium. In order to increase the accuracy of the calculated volume, the arithmetic unit can also use an area wetted by the medium in addition to the determined height. The wetted area can be calculated from the image determined by the first camera.

By determining the metered volume, the delivery of the correct amount of volume through the valve module can be monitored. It is advantageous that on the basis of the determined volume, a constant adaptation or regulation of the metering operations is made possible, which in turn allows the delivery of constant amounts of the medium. The dosing device thus enables the improvement of production processes and an increase in the quality of the components produced.

According to an advantageous embodiment, the arithmetic unit is designed to calculate the volume of the medium metered onto the object also on the basis of the viscosity of the medium and / or a wetting angle and / or the temperature and / or the area covered by the medium. By additionally taking these parameters into account, the dosed volume can be calculated even more precisely. In particular, a geometric shape of the metered medium can be more accurately determined on a component or on the object.

For example, the viscosity and the wetting angle may vary depending on the medium to be metered. The wetting angle is defined as the angle between a surface of the object and a running direction of the boundary of the medium at the edge of the metered medium. The wetting angle can additionally change as a result of the temperature, whereby the wetting angle can become smaller as the temperature decreases.

In particular, a look-up table can be provided in the arithmetic unit, in which the viscosity, customary wetting angles and the like for various media are stored. In addition, the dosing device may comprise a temperature sensor which detects the temperature of the object or the components. The temperature can be detected without contact, for example by means of an infrared sensor.

Preferably, the arithmetic unit is designed to generate a difference image from a camera image with metered medium and a camera image without metered medium. The camera images processed for the differential image can be recorded, for example, by the first and the second camera, with the same location of the object being detected in each camera image. By using a differential image, the metered on the object medium and thus the reflection of the light source can be made very visible. This is particularly advantageous when using transparent media.

Particularly preferably, a plurality of lighting means is provided, wherein the lighting means are arranged in particular in a grid. The lamps can be controlled individually or in groups and preferably be formed of LEDs (light emitting diodes). Due to the individual controllability, the lighting means can be activated such that the reflection of the medium shows, for example, a circular line or a straight line. Due to the long edge of the circular line or the straight line, a particularly accurate and reliable determination of the position of the reflection is possible. As a result, the accuracy of the determination of the height and thus the calculation of the volume of the metered medium is improved. Preferably, a reflection in the form of a circular line is used for punctiform metered medium and a reflection in the form of a straight line for linear metered medium.

To generate a circular line, the bulbs can be switched such that the impression of a glowing circle arises. In a corresponding manner, lighting means are activated which are arranged along a straight line to produce a straight line.

According to a further advantageous embodiment, the lighting means are arranged symmetrically around an objective of the first camera. For example, the bulbs may be arranged in a square area around the lens of the first camera, the lens being in the diagonal intersection of the square area. Due to the symmetrical arrangement, a reflection on the metered medium can be imaged as symmetrical reflection in a camera image. The lighting means can be arranged or activated such that a lighting field of the lighting means coincides with a field of view of the first camera.

The bulbs can be controlled so that with metered medium, which has a low height and a large wetting surface on an object, bulbs are activated, which are arranged near the lens of the first camera. In a corresponding manner, in the case of a medium which has a large height and a small wetting area on an object, illuminants which are far away from the objective can be activated.

According to a further advantageous embodiment, the lighting means define a plane for which a viewing direction of the first camera is a normal vector. In the plane defined by the light source may also be a lens of the first camera.

• – mit einem Ventilmodul ein Medium auf ein Objekt dosiert wird,
• – das dosierte Medium mit einem Leuchtmittel beleuchtet wird,
• – mit einer ersten Kamera ein Bild des beleuchteten dosierten Mediums erfasst wird, und
• – eine Höhe und/oder ein Volumen anhand einer Reflexion von Strahlung des Leuchtmittels an dem dosierten Medium berechnet wird.

The invention also relates to a method in which

• - With a valve module, a medium is metered onto an object,
• The dosed medium is illuminated with a light source,
• - With a first camera, an image of the illuminated metered medium is detected, and
• A height and / or a volume is calculated on the basis of a reflection of radiation of the luminous means on the metered medium.

With regard to the method according to the invention, the statements made with regard to the metering devices according to the invention apply correspondingly, in particular with regard to advantages and preferred embodiments.

In addition, it should be understood that the embodiments of the metering devices according to the invention can be combined with one another as desired. Thus, for example, by means of the second, third and / or fourth camera, a determination of the height and / or the volume of the metered medium can be performed. For this purpose, the arithmetic unit can be coupled to each of the cameras by means of a data connection. Also, lighting means may be provided which are each associated with one of the first, second, third and / or fourth camera.

Hereinafter, the invention will be described purely by way of example with reference to the drawings. Show it:

1 a metering device according to the invention in a perspective view;

2 the metering device of 1 in a schematic view from above;

3 a travel path of a metering device;

4 a plurality of bulbs arranged around a camera;

5 a side schematic sectional view of a camera during the illumination of metered medium;

6A activated bulbs for generating a circular reflection;

6B activated bulbs for generating a strip-shaped reflection;

7A circular dosed medium with a reflection of in 6A shown activated bulbs;

7B linear dosed medium with a reflection of in 6B activated bulbs; and

8th a side schematic sectional view of a camera and a metered medium for the calculation of the volume of the medium.

1 shows a metering device 10 with a valve module 12 , To the valve module 12 is a media store 14 connected, in which there is a medium, namely an adhesive 16 , is located. The adhesive 16 can by means of a (not shown) valve opening on components 18 be dosed. The components 18 are below the valve module 12 arranged on a (not shown) slide.

At the valve module 12 is on a first side wall a first camera 20 and a second camera on a second side wall opposite the first side wall 22 arranged.

At a front of the valve module 12 is a third camera 24 arranged. In the valve module 12 In addition, a fourth camera (not shown) is integrated with respect to the valve opening symmetrical to the third camera 24 is arranged. A viewing direction of all cameras 20 . 22 . 24 is perpendicular to the slide.

The valve module 12 and the cameras 20 . 22 . 24 are via supply lines 26 electrically connected to a (also not shown) computing unit.

2 shows the metering device 10 from 1 in a schematic plan view. In 2 is a square first viewing area 28 which indicates the area of the slide that the first camera 20 can capture. In a similar way, the second, third and fourth camera 22 . 24 a second field of vision 30 , a third field of vision 32 and a fourth viewing area 34 to capture.

The components 18 are arranged along a straight line. In the operation of the metering 10 can the second camera 22 an image of one in the second field of view 30 located component 18 take up. At the same time, adhesive can be applied via the valve opening 16 on one under the valve module 12 located component 18 be dosed. Also at the same time can by means of the first camera 20 that in the first field of vision 28 located component 16 be recorded. That in the first field of vision 28 located component 18 is partially with adhesive 16 covered, something by the first camera 20 is detected. Out of the one with the first camera 20 captured image of the component 18 a difference image can be generated by one of the second camera 22 previously captured image of the same component 18 from the picture of the first camera 20 is subtracted.

When using the dosing device 10 can the metering device 10 be moved so that in succession all components 18 with glue 16 to be covered. In the in 2 As shown, the metering device can 10 move to the left and thus in negative X-direction.

Should a variety of components 18 with glue 16 be provided, so the components 18 , as in 3 shown to be arranged in a matrix-like manner in a uniform grid. The dosing device 10 can then along a travel path 36 be moved to successively the components 18 with glue 16 to provide.

For example, the travel path 36 be selected when the dosing device only the first camera 20 and the second camera 22 includes. The travel path 36 is meander-shaped, wherein the metering device 10 after every line 37 of components 18 over one end of the line 37 moves out to an image of the last component 18 in a row 37 (with glue 16 ) and an image of the respective first component 18 in a row 37 to be able to absorb (without glue). A change of direction in the travel path 36 So only occurs when the valve module on any component 18 located.

Includes the dosing device 10 as in the 1 and 2 shown four cameras 20 . 22 . 24 so can also an alternative path 38 be selected, at which the third camera 24 and the fourth camera each have an image of the first component of the next line 37 and the last component 18 the previous line 37 be able to record. In the alternative travel path 38 becomes the metering device 10 not moved out of the area in which the components 18 are arranged. Instead, a movement occurs after the metering of adhesive 16 on the last component 18 a line 37 directly to the nearest component 18 the next line 37 ,

4 shows a variety of bulbs, which is a camera 20 . 22 . 24 is arranged around. Each of the cameras 20 . 22 . 24 can with the in 4 be shown, which are called LEDs 40 are formed. By way of example, it is assumed below that the LEDs 40 at the first camera 20 are attached.

The LEDs 40 are symmetrical about a lens 42 the first camera 20 arranged around. The LEDs 40 are in a square area 44 arranged and form a grid of straight lines perpendicular to each other. The LEDs 40 can be activated individually by means of the arithmetic unit.

5 shows the first camera 20 in a side sectional view. When taking a picture of a component 18 with adhesive thereon 16 becomes a part of the LEDs 40 activated, causing first rays of light 46 in the direction of the adhesive 16 be emitted. The adhesive 16 reflects the first rays of light 26 , creating second rays of light 48 be generated. The second rays of light 48 be from a lens 50 in the lens 42 distracted and onto a CCD chip 52 the first camera 20 projected. By means of the signal of the CCD chip 52 the arithmetic unit generates an image of the component 18 with adhesive thereon, being on a surface of the adhesive 16 a reflection 56 ( 7A and 7B ) of the LEDs 40 can be seen.

A relative position of the activated LEDs 40 to the lens 42 is known. In addition, the distance between the activated LEDs 40 to the component 18 known. From these known dimensions can be determined where the reflection 56 The light of the activated LEDs would have to be perceived by the camera when there is no glue 16 on the component 18 located. Based on the actual position of the reflection 56 in the captured image where the reflection 56 on the glue 16 can be done, the height of the location of the reflection 56 above the component 18 and thus the height and volume of the adhesive 16 be determined. In particular, a curvature of that of the adhesive 16 formed drop at the place of reflection 56 be determined.

To a particularly accurate determination of the position of the reflection 56 to allow the LEDs 40 be activated such that, for example, a round or line-shaped reflection pattern on the adhesive 16 arises. 6A shows activated LEDs 54 that together define a circle. Through the activated LEDs 54 from 6A can glue on a circularly dosed amount 16 in the 7A reflections shown 56 arise. By the majority of the reflections 56 can be a height and therefore a volume of the glue 16 be calculated with multiple readings, creating a Accuracy of the determination of the volume or the height can be greatly improved.

Alternatively to the in 6A shown activated LEDs 54 can z. B. for smaller amounts of adhesive 16 LEDs 40 to be activated, the closer to the lens 42 lie. This will ensure that a reflection 56 not outside the glue 16 takes place, for example, by the component 18 even.

In the 6A shown activated LEDs 54 are in edge areas of the surface area 44 arranged. An activation of these LEDs 40 especially occurs when the adhesive 16 (or another medium) is particularly flat on the component 18 distributed. The reflections 56 the LEDs 40 in the edge area then appear with sufficient distance to each other and allow a distinction of the individual reflections.

To determine the volume of linear metered adhesive 16 can each have LEDs 40 activated, which are arranged along a straight line. Such activated LEDs 54 are in 6B shown, with associated reflections 56 on a linear metered adhesive 16 in 7B are shown.

Due to the form of a cylinder segment form of the adhesive 16 in 7B become the reflections 56 in 7B of four activated LEDs 54a generated, leading to the lens 42 have the smallest distance.

The remaining activated LEDs 54 are used to generate stray light to the adhesive 16 illuminate enough bright to z. B. that of the adhesive 16 to determine the covered area.

To determine the height and volume of the in 7B The adhesive shown may increase the height and thus the volume of the adhesive 16 sections are determined based on the shape of a cylinder segment.

The calculation of the volume of medium will now be made with reference to 8th explained. 8th shows glue 16 which has the shape of a circle segment in cross section. Such a form of adhesive 16 is also in 6A (in plan view) shown. The diameter of the circle underlying the circle segment is referred to as circle radius R. The circle segment has on the surface of the component 18 a diameter of 2 · r (in 6A denoted as diameter D) and a height h. The diameter is made from the size of the adhesive 16 in a picture of the first camera 20 determined and is therefore known.

Above the glue 16 are the lens 42 the first camera 20 and an activated LED 54 arranged. The first ray of light 46 the LED 54 becomes a viewing direction of the lens 42 at an angle α from the LED 54 emitted. The angle α is from the known relative position of the LED 54 to the lens 42 determined and is therefore also known.

The one from the glue 16 reflected second light beam 48 becomes the lens 42 reflected, wherein the second light beam 48 with a distance a from a center or an axis of symmetry 58 of the lens 42 parallel to the axis of symmetry 58 runs. The distance a may also be from an image of the first camera 20 be determined as in 6A can be seen, and is well known.

The volume V of the circular segment-shaped adhesive 16 from 8th can be calculated according to the formula V = 1/3 · π · h ² · (3 · R - h), wherein the height h and the circle radius R are initially unknown.

By means of in 8th shown right-angled triangle 60 the circle radius R can be calculated using the formula R ² = r ² + (R - h) ² . From this formula we obtain for the height h: h = R - (R ² - r ² )) ^½ .

Due to the law of reflection is a straight line 62 with the axis of symmetry 58 includes the angle β, an angle bisector for the angle α. This results in β = α / 2. Straight 62 passes through the place of reflection 56 and through the center of the circle underlying the circle segment. Straight 62 has the length R.

In addition, results from another right triangle 64 , which is from the axis of symmetry 58 , the distance a and the straight line 62 is formed, the relationship sin (β) = a / R.

The circle radius R is thus calculated as R = a / sin (α / 2). Furthermore, for the height h = a / sin (α / 2) - ((a / sin (α / 2)) ² -r ² ) ^1/2 .

The height h and the circle radius R are therefore known. The volume of the adhesive 16 can thus be calculated from the formula V = 1/3 * π * h ² * (3 * R-h).

LIST OF REFERENCE NUMBERS

10

metering

12

valve module

14

media storage

16

adhesive

18

component

20

first camera

22

second camera

24

third camera

26

supply line

28

first field of vision

30

second field of vision

32

third field of vision

34

fourth viewing area

36

Verfahrpfad

37

row

38

alternative travel path

40

LED

42

lens

44

square area

46

first light beam

48

second light beam

50

lens

52

CCD chip

54, 54a

activated LED

56

reflection

58

axis of symmetry

60

right triangle

62

Just

64

another right triangle

Claims (11)

Dosing device ( 10 ) for automated dosing of a fluid medium ( 16 ), comprising a valve module ( 12 ) with a connection for a media storage ( 14 ) and a valve opening and a first camera ( 20 ) connected to the valve module ( 12 ), characterized by a second camera ( 22 ) connected to the valve module ( 12 ) is attached. Dosing device ( 10 ) according to claim 1, characterized in that the first and the second camera ( 20 . 22 ) on two, in particular opposite, sides of the valve module ( 12 ) on the valve module ( 12 ) are mounted. Dosing device ( 10 ) according to claim 1 or 2, characterized in that the first camera ( 20 ), the second camera ( 22 ) and the valve opening are arranged along a straight line. Dosing device ( 10 ) according to at least one of the preceding claims, characterized by a third camera ( 24 ), in particular on the valve module ( 12 ) is attached. Dosing device ( 10 ) for automated dosing of a fluid medium ( 16 ) on an object ( 18 ), comprising a valve module ( 12 ) with a connection for a media storage ( 14 ) and a valve opening, at least a first camera ( 20 ) connected to the valve module ( 12 ) and at least one with the first camera ( 20 ) and with respect to the first camera ( 20 ) fixedly arranged light source ( 40 ), which is designed to be the object ( 18 ), characterized by a computing unit which is formed on the basis of a reflection of radiation of the at least one light source ( 40 ), a height of the object ( 18 ) metered medium ( 16 ) to investigate. Dosing device ( 10 ) according to claim 5, characterized in that the arithmetic unit is formed, a volume of the object ( 18 ) metered medium ( 16 ) calculated on the basis of the determined height. Dosing device ( 10 ) according to claim 6, characterized in that the arithmetic unit is formed, the volume of the object ( 18 ) metered medium ( 16 ) also based on the viscosity of the medium ( 16 ) and / or a wetting angle and / or the temperature and / or of the medium ( 16 ) covered area. Dosing device ( 10 ) according to at least one of claims 5 to 7, characterized in that the arithmetic unit is formed, a difference image from a camera image with metered medium ( 16 ) and a camera image without metered medium ( 16 ) to create. Dosing device ( 10 ) according to at least one of claims 5 to 8, characterized in that a plurality of lighting means ( 40 ) is provided, wherein the bulbs ( 40 ) are arranged in particular in a grid. Dosing device ( 10 ) according to claim 9, characterized in that the lighting means ( 40 ) symmetrically about a lens ( 42 ) of the first camera ( 20 ) are arranged around. Dosing device ( 10 ) according to claim 9 or 10, characterized in that the lighting means ( 40 ) define a plane for which a viewing direction of the first camera ( 20 ) is a normal vector.

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