JP-2026075904-A - Droplet discharge device

JP2026075904AJP 2026075904 AJP2026075904 AJP 2026075904AJP-2026075904-A

Abstract

[Problem] To provide a droplet dispensing device that can shorten the total processing time for detecting dispensing defects. [Solution] The droplet dispensing device comprises a dispensing head having multiple nozzles, a light source that emits light toward the flight space, a light receiving unit that detects the amount of light received after the light emitted from the light source has passed through the flight space, and a control device. The control device performs a first reference waveform acquisition process that acquires a reference waveform of the signal for a droplet dispensed by one nozzle as a first reference waveform, a detection waveform process that acquires a detected waveform of the signal for a droplet dispensed by one nozzle, a second reference waveform acquisition process which is performed after the first reference waveform acquisition process and acquires a reference waveform of the signal for a droplet dispensed by a nozzle other than the first nozzle as a second reference waveform, and a first calculation process which is performed in parallel with the second reference waveform acquisition process and calculates the correlation between the first reference waveform and the detected waveform. [Selection Diagram] Figure 6

Inventors

伊藤敦
加藤雄哉
高山治久

Assignees

ブラザー工業株式会社

Dates

Publication Date: 20260511
Application Date: 20241023

Claims (4)

A dispensing head having multiple nozzles for dispensing droplets onto the printing medium, A light source that emits light toward the flight space in which the droplet ejected from the nozzle is flying, A light receiving unit that detects the amount of light received after the light emitted from the light source has passed through the flight space and outputs a signal, A control device is provided, The control device is A first reference waveform acquisition process that acquires the reference waveform of the signal for the droplet discharged by the nozzle as a first reference waveform, A detection waveform processing method is used to obtain the detection waveform of the signal for the droplet ejected by the first nozzle, A process performed after the first reference waveform acquisition process, the second reference waveform acquisition process which acquires a reference waveform of the signal for the droplet discharged by a nozzle other than the first nozzle as a second reference waveform, A droplet dispensing device that performs a process in parallel with the second reference waveform acquisition process, the first calculation process which calculates the correlation between the first reference waveform and the detected waveform.
The control device is A position acquisition process to acquire the position of each nozzle, The droplet dispensing device according to claim 1, which performs a reference waveform acquisition process to acquire the reference waveform corresponding to each nozzle according to the position of each nozzle.
The control device is A second calculation process for calculating the correlation for the other nozzles, The droplet dispensing apparatus according to claim 1, comprising: a process executed in parallel with the second calculation process, which determines whether or not there is a dispensing defect with respect to one nozzle based on the calculation result of the first calculation process.
The droplet dispensing device according to claim 3, wherein the control device performs a part of the specific processing for one nozzle in parallel with the second calculation processing performed for the other nozzle after the specific processing.

Description

This disclosure relates to a droplet ejection device used in printing devices such as inkjet printers. Conventionally, a liquid dispensing failure detection device is known that comprises a dispensing head with a nozzle, a light-emitting element, and a light-receiving unit (Patent Document 1). The light-receiving unit includes a light-receiving element and a current-voltage conversion circuit. The light-receiving element outputs a current corresponding to the intensity of the received light. The current-voltage conversion circuit converts the current output by the light-receiving element into a voltage and outputs it. Waveform data is obtained based on the output voltage from the current-voltage conversion circuit, and dispensing failures are detected based on predetermined feature quantities in the waveform data. Japanese Patent Publication No. 2012-218258 This is a plan view showing a droplet dispensing device according to one embodiment of the present disclosure.Figure 1 is a cross-sectional view showing the configuration of the discharge head.This is a block diagram showing the components of a printing apparatus equipped with a droplet ejection device, as shown in Figure 1.This is a block diagram showing the functional configuration of the control device in Figure 3.This diagram shows how a laser beam is shone onto ink droplets being ejected from the ejection head while they are in flight.This is an explanatory diagram illustrating an example of how multiple tasks are executed in parallel during the ejection failure detection process.This is a diagram showing the beam waist portion of a laser beam.Figure 8A shows the illuminance distribution including the illuminance (central illuminance) at the position of the optical axis of the laser beam, and Figure 8B shows the illuminance distribution including the illuminance at a position a certain distance away from the optical axis in the radial direction of the laser beam.This figure shows the dimensions of the laser beam in a direction perpendicular to the radial direction of the laser beam shown in Figure 8B.This is an explanatory diagram illustrating an example of how multiple tasks are executed in parallel during the ejection failure detection process.This is an explanatory diagram illustrating an example of how multiple tasks are executed in parallel during the ejection failure detection process. The droplet dispensing apparatus according to the embodiments of this disclosure will be described below with reference to the drawings. The droplet dispensing apparatus described below is merely one embodiment of this disclosure. Therefore, this disclosure is not limited to the following embodiments, and additions, deletions, and modifications are permitted without departing from the spirit of this disclosure. Figure 1 is a perspective view showing a droplet ejection device 100 according to one embodiment of this disclosure. Figure 2 is a cross-sectional view showing the configuration of the ejection head 10 in Figure 1. Figure 3 is a block diagram showing the components of a printing apparatus 1 equipped with the droplet ejection device 100 of Figure 1. Figure 4 is a block diagram showing the functional configuration of the control device 20 in Figure 3. In Figures 1 and 2, mutually orthogonal directions are denoted as the first direction Ds, the second direction Df, and the third direction Dz. In this embodiment, for example, the first direction Ds is the direction of movement of the carriage 3 (described later), the second direction Df is the direction of transport of the printing medium W (described later), and the third direction Dz is the vertical direction. In the following description, Ds will be referred to as the direction of movement, Df as the transport direction, and Dz as the vertical direction. As shown in Figures 1 and 3, the droplet ejection device 100 comprises, for example, two ejection heads 10 (10A, 10B), two ultraviolet irradiation devices 40 (40A, 40B), a carriage 3 on which the ejection heads 10 and ultraviolet irradiation devices 40 are mounted, a storage tank 62, a pair of guide rails 63, and a controller unit 19 including a control device 20. In this embodiment, an inkjet head that ejects ultraviolet-curable ink droplets Id (Figure 5 below) is exemplified as the ejection head 10. However, the form of the ejection head 10 is not limited. If the ejection head 10 ejects ordinary ink droplets that are not ultraviolet-curable ink droplets, the ultraviolet irradiation devices 40 are not necessary. In this embodiment, ink droplets Id correspond to liquid droplets. The carriage 3 is supported by a pair of guide rails 63 extending in the direction of movement Ds, and reciprocates along these guide rails 63 in the direction of movement Ds. This causes the two discharge heads 10 (10A, 10B) and the two ultraviolet irradiation devices 40 (40A, 40B) to reciprocate in the direction of movement Ds. The discharge heads 10 are connected to the storage