초록 ▼

The subject matter of the invention is a method for a printing machine with a printing device (5), in particular an inkjet printer, for applying liquid (22) onto a print material, with monitoring of the quantity of liquid in a liquid supply unit (1) by measuring the liquid level (23) with a sequenti

The subject matter of the invention is a method for a printing machine with a printing device (5), in particular an inkjet printer, for applying liquid (22) onto a print material, with monitoring of the quantity of liquid in a liquid supply unit (1) by measuring the liquid level (23) with a sequential controller, wherein the measurement of the liquid level (23) is performed by a device (11), which detects the presence of liquid at the output of the printing device (5). Another subject matter of the invention is a liquid supply unit (1) for a printing machine with a printing device (5), in particular, an inkjet printer, for applying liquid (22) on a print material, with monitoring of the quantity of liquid in a liquid supply unit (1) by measuring the liquid level (23) with a sequential controller, wherein the measurement device (11) is suitable for measuring a fill level (23) and for controlling a liquid device (3). Furthermore, a measurement device (11), in particular, for a liquid supply unit (1), is the subject matter of the invention, in which at least one part of the measurement device (11) is made from circuit-board material.

대표청구항 ▼

1. A method for a printing machine with a printing device to apply liquid onto a print material, the method comprising: supplying liquid with a liquid device via a supply opening into a lower reservoir of a housing comprising a print head, wherein the lower reservoir comprises an outlet opening that

1. A method for a printing machine with a printing device to apply liquid onto a print material, the method comprising: supplying liquid with a liquid device via a supply opening into a lower reservoir of a housing comprising a print head, wherein the lower reservoir comprises an outlet opening that is connected with a measurement device;detecting a liquid level in an upper chamber of the measurement device with a sensor;converting the detected liquid level into a measurement signal value;comparing the measurement signal value to a threshold by evaluation electronics; andactivating the liquid device when the evaluation electronics determine that the measurement signal value is below the threshold based on the comparison;wherein rises up into the chamber of the upper measurement device via the outlet opening of the reservoir when the reservoir is filled with liquid supplied by the liquid device; andwherein when the lower reservoir is completely filled, liquid from the lower reservoir rises into the upper chamber of the measurement device via the outlet opening of the lower reservoir when the lower reservoir is filled with liquid supplied by the liquid device; andwherein, when the liquid level in the upper chamber drops below a minimum fill level, the liquid device is turned on until a maximum fill level in the chamber is equaled or exceeded so that the lower reservoir is always completely filled with liquid. 2. The method according to claim 1, characterized in that the detection of the liquid level in the upper chamber is performed by a capacitive sensor. 3. The method according to claim 2, characterized in that the capacitive sensor detects the liquid level, and converts the detected level into the measurement signal value. 4. The method according to claim 3, characterized in that the evaluation electronics are integrated on the sensor. 5. The method according to claim 4, characterized in that a signal generated by the evaluation electronics is fed to a device controller. 6. The method according to claim 5, characterized in that the device controller turns on or off the liquid device. 7. A liquid supply unit for a printing machine with a printing device for applying liquid onto a print material with monitoring of the quantity of liquid in the liquid supply unit by measuring the liquid level with a sequential controller, the liquid supply unit comprising: a storage container containing the liquid;a housing comprising a supply opening and an outlet opening and a lower reservoir and a print head,wherein the lower reservoir is connected via an outlet opening to a measurement device comprising an upper chamber,wherein the lower reservoir is connected via the supply opening with the storage container,wherein the measurement device comprises a sensor to measure the liquid level in the upper chamber;wherein a liquid device is activated when the measurement device compares the liquid level in the upper chamber to a threshold and determines that the liquid level measured in the upper chamber is below the threshold;wherein liquid is supplied from the storage container to the reservoir of the printing device via a liquid line after activating the liquid device;wherein liquid in the filled lower reservoir rises up into the upper chamber of the measurement device via the outlet opening of the lower reservoir when the reservoir is supplied with liquid by the liquid device; andwherein, when the liquid level in the upper chamber drops below a minimum fill level, the liquid device is turned on until a maximum fill level in the chamber is equaled or exceeded so that the lower reservoir is always completely filled with liquid. 8. The liquid supply unit according to claim 7, characterized in that the measurement device comprises a sensor and evaluation electronics that are connected to the sensor. 9. The liquid supply unit according to claim 8, characterized in that the sensor of the measurement device detects different liquid levels in the upper chamber. 10. The liquid supply unit according to claim 8, characterized in that the sensor comprises several planar elements that contact each other in a sandwiched arrangement, wherein a middle element forms the chamber by means of a removed area, and at least one part of the measurement device is made from circuit-board material. 11. The liquid supply unit according to claim 10, characterized in that the sensor has a supply flange with an inlet opening, wherein the chamber is connected to the inlet opening. 12. The liquid supply unit according to claim 11, characterized in that the sensor contains an overflow flange connected to the upper chamber with an overflow opening, and wherein the overflow opening is connected to a valve. 13. The liquid supply unit according to claim 10, characterized in that parts of the sensor are made from a conductive material, and wherein an electrode and/or the evaluation electronics are mounted on the circuit-board material. 14. The liquid supply unit according to claim 13, characterized in that the evaluation electronics are connected to a connector plug for supplying power via at least one track conductor. 15. The liquid supply unit according to claim 13, characterized in that the evaluation electronics are connected to at least one track conductor for signal processing. 16. The liquid supply unit according to claim 15, characterized in that the track conductor is guided to a contact element that is suitable for a device controller of a device. 17. The liquid supply unit according to claim 13, characterized in that the electrode and the evaluation electronics are connected to each other by means of contact elements and by means of track conductors on the circuit-board material. 18. The liquid supply unit according to claim 10, characterized in that the planar elements are constructed of circuit-board material with track conductors embedded in plastic. 19. The liquid supply unit according to claim 18, characterized in that at least one planar element is constructed as a carrier for an electrode. 20. The liquid supply unit according to claim 19, characterized in that the electrode is arranged in at least one planar element. 21. The liquid supply unit according to claim 20, characterized in that the electrode forms at least one part of an inner wall of the upper chamber. 22. The liquid supply unit according to claim 21, characterized in that the electrode has a planar construction. 23. The liquid supply unit according to claim 10, characterized in that the sensor is formed from three planar elements. 24. The liquid supply unit according to claim 23, characterized in that a first outer element of the three planar elements is laminated on two sides, and a second outer element of the three planar elements is laminated on one side. 25. The liquid supply unit according to claim 10, characterized in that the middle element is equipped with connecting and/or positioning elements for the outer elements. 26. The liquid supply unit according to claim 7, characterized in that a sensor is arranged on the outlet opening of the housing of the printing device. 27. The liquid supply unit according to claim 7, characterized in that the sensor is constructed and arranged as part of the upper chamber.