Image forming apparatus

Patent metadata

Field	Value
Publication number	US-2023405994-A1
Application number	US-202318328086-A
Country	US
Kind code	A1
Filing date	Jun 2, 2023
Priority date	Jun 8, 2022
Publication date	Dec 21, 2023
Grant date	—

Abstract

The controller moves a movable body along a moving direction. A recording head and a detector are mounted on the movable body. The detector detects a detection target fixed to an ink receiving unit. The ink receiving unit receives an ink jetted from the recording head at a time of a flushing. The controller obtains, based on a signal from an encoder, a position of the movable body in a case that the detection target is detected by the detector during movement of the movable body. The controller determines a start timing of the flushing based on the obtained position of the movable body.

First claim

What is claimed is:

1 . An image forming apparatus comprising:
a motor; a movable body configured to be moved by the motor along a predetermined moving direction; a recording head mounted on the movable body and configured to jet ink onto a sheet while being moved together with the movable body to form an image on the sheet; an ink receiving unit configured to receive the ink jetted from the recoding head at a time of executing a flushing and fixed so as not to be moved together with a movement of the movable body; a detection target fixed directly or indirectly to the ink receiving unit; a detector mounted on the movable body and configured to detect the detection target; an encoder configured to output a signal in accordance with a rotation amount of the motor or a moving amount of the movable body; a position detecting section configured to detect a position of the movable body based on the signal outputted from the encoder; and a controller, wherein the controller is configured to execute:
a moving processing for moving the movable body along the moving direction;
a position obtaining processing for obtaining a position, of the movable body, from the position detecting section in a case that the detection target is detected by the detector during the movement of the movable body in the moving processing;
a determining processing for determining a start timing of the flushing based on the position, of the movable body, obtained in the position obtaining processing; and
a flushing processing for starting the flushing in accordance with the start timing determined in the determining processing.

2 . The image forming apparatus according to claim 1 , wherein
in the determining processing, the controller is configured to determine, as the start timing, a flushing starting position which is a position, of the movable body, in a case that the flushing is started, and in the flushing processing, the controller is configured to start the flushing at the flushing starting position determined in the determining processing.

3 . The image forming apparatus according to claim 1 , wherein
in the flushing processing, in response to reaching of the movable body to a reference position as a result of the movement of the movable body in the moving direction, the controller is configured to start the flushing after elapse of a prescribed time since a timing at which the movable body reaches the reference position, while the controller continues the movement of the movable body, and in the determining processing, the controller is configured to determine the prescribed time as the start timing.

4 . The image forming apparatus according to claim 2 , wherein in the determining processing, the controller is configured to determine the flushing starting position based on a positional deviation as a difference between a position, of the movable body, obtained in the position determining processing and a design position, of the movable body, at which the detection target is to be detected by the detector.

5 . The image forming apparatus according to claim 4 , wherein in the determining processing, the controller is configured to determine the flushing starting position by correcting, based on the positional deviation, a theoretical starting position which is a design position of the movable body, which is previously determined and at which the flushing is to be started.

6 . The image forming apparatus according to claim 4 , wherein
the moving processing includes:
a first moving processing for moving the movable body in the moving direction so that the detection target is detected by the detector, and then moving the movable body in an opposite direction opposite to the moving direction toward an upstream, in the moving direction, with respect to the ink receiving unit; and
a second moving processing for moving the movable body in the moving direction after executing the first moving processing so that the recording head passes the ink receiving unit,
in the position obtaining processing, the controller is configured to obtain a position, of the movable body, from the position obtaining part in a case that the detection target is detected by the detector during the movement of the movable body in the moving direction in the first moving processing, and in the flushing processing, the controller is configured to start the flushing during the movement of the movable body in the second moving processing.

7 . The image forming apparatus according to claim 6 , wherein
in a case of forming the image on the sheet, the controller is configured to execute a pre-processing for performing reciprocal moving of the movable body in the moving direction prior to formation of the image, for a specified object which is different from the formation of the image, and the first moving processing is included in the reciprocal moving of the movable body in the pre-processing.

8 . The image forming apparatus according to claim 7 , wherein
the detector is configured to detect the sheet, and the specified object includes detection of presence or absence of the sheet and/or detection of a width in the moving direction of the sheet, based on a result of detection of the sheet by the detector.

9 . The image forming apparatus according to claim 6 , further comprising another detection target which is provided separately from the detection target and which is fixed directly or indirectly to the ink receiving unit.

10 . The image forming apparatus according to claim 9 , wherein
the detection target is arranged on the upstream in the moving direction with respect to the ink receiving unit, and the another detection target is arranged on a downstream in the moving direction with respect to the ink receiving unit.

11 . The image forming apparatus according to claim 9 , wherein
in the position obtaining processing, the controller is configured to obtain, from the position detecting section, a first detection position which is a position of the movable body in a case that the detection target is detected by the detector and a second detection position which is a position of the movable body in a case that the another detection target is detected by the detector, and in the determining processing, the controller is configured to determine the flushing starting position based on a first positional deviation and a second positional deviation, the first positional deviation being a difference between the first detection position and a design position, of the movable body, at which the detection target is to be detected by the detector, the second positional deviation being a difference between the second detection position and a design position, of the movable body, at which the another detection target is to be detected by the detector.

12 . The image forming apparatus according to claim 11 , wherein in the determining processing, the controller is configured to determine, based on a formula (1) and a formula (2), the flushing starting position satisfying the formula (1) and the formula (2):

Pst
=

Pst
⁢
0

-

Δ
⁢
P

(

Assignees

• Brother Ind Ltd

Inventors

• Shirai Haruhisa
• Arakawa Yuta
• Sato Shoji
• Tanaka Nobumasa
• Hoga Masahiro

Classifications

• B41J2/1652 Primary

  by driving a fluid through the nozzles to the outside thereof, e.g. by applying pressure to the inside or vacuum at the outside of the print head · CPC title

• B41J19/207 Primary

  Encoding along a bar · CPC title

• B41J2/16526

  by applying pressure only · CPC title

• B41J2/16508

  connected with the printer frame · CPC title