Device and method for checking the level of moving transparent containers
Device for checking the fill level of moving transparent containers comprising at least one light sensitive sensor unit, a light source directed to the sensor unit, and an evaluation unit for sensor signals generated by the sensor unit, whereas the sensor unit generates sensor signals depending on the position of a light beam on the sensor unit, and the evaluation unit determines from the temporal sequence of the sensor signals, whether the light beam was deflected by a container filled with a product.
1. Device for check in the level of moving transparent containers comprising
at least one light sensitive sensor unit,
a light source directed to the sensor unit, and
an evaluation unit for sensor signals generated by the sensor unit, characterized in that
the sensor unit generates sensor signals depending on the position of a light beam on the sensor unit, and
the evaluation unit determines from the temporal sequence of the sensor signals, whether the light beam was deflected by a container filled with a product.
2. Device according to claim 1 , characterized in that the light sensitive sensor unit comprises a light sensitive position sensor (PSD) indicating the position of incident light beams.
3. Device according to claim 1 , characterized in that the sensor unit comprises two sensors or two sensor areas adapted to generate sensor signals independent of each other wherein a light beam is directly directed on a first sensor or first sensor area and the light beam impinges on the second sensor or second sensor area if it is deflected by a container filled with a product.
4. A device for checking the level of moving transparent containers comprising:
at least one light sensitive sensor unit,
a light source directed to the sensor unit, and
an evaluation unit for sensor signals generated by the at least one sensor unit, wherein:
at least one sensor unit generates sensor signals depending on the position of a light bean on the at least one sensor unit,
the evaluation unit determines from the temporal sequence of the sensor signals whether the light beam was deflected by a container filled with a product,
the at least one sensor unit comprises at least three sensor areas one being a first sensor area, one being a second sensor area, and one being a third sensor area, each sensor area comprises at least one sensor, each sensor area is adapted to generate sensor signals independent of each other,
wherein a light beam is directly directed on a first sensor area and the light beam impinges on the second sensor area if it is deflected by a container filled with a product, the tree sensor areas being in three different positions,
at least the second and the third sensor areas are located in at least one relative position selected from the list consisting of: before the first sensor area with respect to the direction of movement of the transparent container and behind the first sensor area with respect to the direction of movement of the transparent container, and
wherein the light beams deflected by a container filled with the product impinge on the three different areas in a temporal sequence.
5. Device according to claim 4 , characterized in that three sensor areas are provided, wherein a second sensor area is provided before the first sensor area with respect to the direction of movement of a transparent bottle and a third sensor area is provided behind the first sensor area with respect to the direction of movement of a transparent bottle.
6. Device according to claim 5 , characterized in that the evaluation unit generates a signal indicating a sufficient level in the container in response to the following sequence of sensor signals: second sensor area, first sensor area, and third sensor area, respectively.
7. Device according to claim 6 , characterized in that the evaluation unit generates the signal indicating a sufficient level of the transparent container in response to a missing first sensor signal for the said sequence of signals.
8. Device according to claim 3 characterized in that the light sensitive sensor unit comprises photo transistors and/or photo diodes.
9. Device according to claim 3 characterized in that the light sensitive sensor unit comprises a CCD-chip or a CCD-array of light sensitive photo elements, wherein the sensor area is defined by areas of the light sensitive photo elements.
10. Device according to claim 1 characterized in that a diode-laser module is provided as light source.
11. Device according to claim 10 , characterized in that the diode-laser module provides light at a wavelength such that the container material and the product are transparent.
12. Device according to claim 1 characterized in that the light source is adjustable in its height relative to the moving containers.
13. Device according to claim 1 characterized in that two light sources are provided in different height relative to the moving containers.
14. Device according to claim 13 , characterized in that the light sources are directed to a common sensor unit wherein the light sources alternatingly direct a light beam to the common sensor unit.
15. Method for controlling the level of moving, transparent containers comprising the following steps:
directing a light beam to the moving container in an area of a predetermined fill level height,
a sensor unit measures the position of the light beam going through the container, and
an evaluation unit determines from the temporal sequence of the light beams measured by a sensor unit whether the light beam was deflected by the moving container filled with a product.
16. Method according to claim 15 , characterized in that the evaluation unit responds to a temporarily changing position of the measured light beams in the direction of movement of the container and generates a signal indicating the sufficient level of the container.