JP2755960B2 - Liquid jet recording device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION The present invention relates to a liquid jet recording apparatus.

[Related Art] A liquid jet recording apparatus (inkjet recording apparatus) that discharges a recording liquid from a recording head to record information such as characters and images is widely known.

Paper or plastic sheet (hereinafter referred to as recording paper) is mainly used as the recording material of this type of apparatus. The operating noise is low compared to other recording methods, and the basic mechanical structure is simple and inexpensive. Computer,
It has been adopted in various fields as a recording output device such as a word processor.

On the other hand, there has been proposed a recording apparatus using a recording head in which ink discharge ports are arranged in a number corresponding to the entire width in the width direction of a recording material (hereinafter, referred to as a line head). Further, a color recording apparatus in which a plurality of such recording heads are arranged corresponding to a plurality of ink colors has been proposed.

In such a recording apparatus, a recording material is held by electrostatic attraction of a belt or the like forming a part of a transport system, and one or a plurality of line heads are arranged along the transport path to transport the recording material. A single color or color recording is performed in the process.

[Problems to be Solved by the Invention] In the above conventional example, a continuous paper feeding method of cut paper having a belt-shaped (band-shaped) member is particularly suitable for high-speed recording. The gap between the recording head and the recording paper tends to fluctuate due to vibration.If the gap is small, the recording paper may come into contact with the recording head, causing recording dirt and clogging of the discharge port. However, there is a possibility that jamming may occur by hitting the recording head. Further, even when the gap is widened, the deviation of the landing position of the ink on the recording paper due to the slight bending when the ink is ejected from the ejection port is amplified, and there is a possibility that the recording quality may be deteriorated.

An object of the present invention is to solve such a problem by suppressing the vibration of the belt.

[Means for Solving the Problems] For this purpose, the present invention relates to a liquid jet recording apparatus that performs recording on the recording material by a plurality of liquid jet recording heads arranged along the transport direction of the recording material. Transport means having a belt-like member for transporting a recording material to a region where the liquid jet recording head can record, and a back surface of the recordable region of the recording material placing surface of the belt-like member on which the recording material is placed; And a plurality of liquid jet recording heads located at the recording position at positions separated from the recording material mounting surface of the band-shaped member, the support members being arranged at portions corresponding to the side and supporting the band-shaped member. A plurality of cap members arranged adjacent to each other and the plurality of liquid jet recording heads execute recording on the recording material in proximity to the recording material mounting surface of the band-shaped member. Recording position And a head moving means for integrally moving the cap member to a capping position where capping is performed by the cap member.

[Operation] According to the present invention, the support member for supporting the back surface side of the recording material mounting surface of the belt-shaped member constituting a part of the conveying means is provided, so that the belt-shaped member at a position facing the recording head is provided. Vibration is suppressed. Further, according to the present invention, from the capping position at a position separated from the recording material mounting surface of the band-shaped member, to a recording position close to the recording material mounting surface of the band-shaped member,
Even if multiple liquid jet recording heads are moved as one,
Since the recording material does not vibrate, there is no contact with any of the plurality of recording heads. Further, since the plurality of recording heads and the plurality of cap members corresponding to each of the recording heads are arranged adjacent to each other, the mutual movement distance between the recording head and the cap member can be reduced, and the size can be reduced. be able to.

Examples Hereinafter, the present invention will be described in detail with reference to the drawings.

 FIG. 1 shows an embodiment of the present invention.

Here, 1 is a line head type recording head,
On the lower surface, for example, 3456 ejection ports are provided at an interval of 16 dots / mm, and recording with a width of 216 mm is performed in line order. In this example, 1a, 1b, 1c, and 1d correspond to four color inks of yellow, cyan, magenta, and black, respectively.
Are provided, and each of the recording heads is fixedly supported by the holder 2 so that the interval between the ejection ports in the recording paper transport direction is constant. These four
A head unit constituted by the recording head and the holder 2 can be moved up and down in the figure by a head moving means 24 composed of a drive source such as a motor and a transmission mechanism such as a gear. That is, since the head unit is configured to include the four recording heads 1a to 1d, the four recording heads 1a to 1d can be integrally moved by the head moving means 24.

Reference numeral 3 denotes a cap mounted on the orifice surface of the recording head at the time of non-recording, and can be moved in the X direction by cap moving means 25 including a drive source such as a motor and a transmission mechanism such as a gear. The cap 3 has, for example, a sponge-like ink absorbing member inside, and is configured to receive ink discharge (idle discharge) from the recording head 1 for a recovery operation. The cap 3 includes a plurality (four in this embodiment) of cap members 3a to 3d corresponding to the plurality of (four in this embodiment) recording heads 1a to 1d, respectively. These cap members 3a to 3d are arranged at positions opposing the respective ejection opening surfaces of the recording heads 1a to 1d at the capping position, and are adjacent to the corresponding recording heads 1a to 1d at the recording position and are also adjacent to the respective recording heads 1a to 1d. It is arranged at a position sandwiched between 1d.

Reference numeral 4 denotes an ink tank corresponding to each recording head, and ink is guided to each recording head 1 (1a to 1d) via an ink supply tube 5 (5a to 5d). Here, the supply of the ink utilizes the capillary phenomenon of the nozzles arranged in the recording head 1, and the head of the ink in each ink tank is set lower than the discharge port surface by a certain distance.

Reference numeral 6 denotes a seamless belt as a belt-like member for conveying the recording paper, and the surface of the belt is neutralized. Then, the recording paper 27 is charged by the charger 12 and electrostatically attracted to the belt 6, so that the recording paper 27 is surely conveyed toward a region where the recording heads 1a to 1d can record. The belt 6 is driven by the motor 8 connected to the belt driving roller 7 to convert the recording paper 27 into X.
It is rotated in the direction to move in the direction. 9 is the belt 6
Reference numeral 10 denotes a tension roller for applying a constant tension to the belt 6. 11a
Reference numerals 11b and 11b denote pinch rollers which press the recording paper 27 against the belt 6 before and after the charger 12 to enhance the suction.
The recording paper 27 fed by the roller a and the belt of the roller 9a is received, looped in the guide 13, and also functions as a registration roller for improving the direct attachment of the leading end of the recording paper in the X direction. The transport belt 6, the belt driving roller 7, the motor 8, the idle roller 9, the tension roller 10, the pinch rollers 11a and 11b, the charger 12, and the guide 13 can record the recording paper 27 by the recording heads 1a to 1d. Conveying means for conveying toward the area is configured.

The recording paper 27 is sent out one by one from the cassette 26 by the paper feed roller 16, is sandwiched between the transport roller 14 and the pinch roller 15, and is guided to the above-described registration roller section.
A cleaning unit 17 removes paper dust and the like on the belt 6. Reference numeral 18 denotes a discharge tray on which recorded recording paper is stacked;
And a belt supporting member as a supporting member that regulates any of the belts 6 and suppresses vibration, and is formed in a flat plate shape in this example.

Reference numeral 19 denotes a control circuit for controlling each unit according to the control procedure shown in FIG.
U, a ROM storing a program corresponding to the control procedure shown in FIG. 2, a working RAM, and the like. Reference numeral 20 denotes a head driver for driving the recording heads 1a to 1d under the control of the control circuit 19; 21, a motor driver for driving the belt driving motor 8; 22, a charger driver for driving the charger 12; Similarly, the motor driver drives a transport motor 33 coupled to the transport roller 14. The operation of the head moving means 24 and the cap moving means 25 is also controlled by the control circuit 19.
Is controlled by

FIG. 2 is a flowchart showing an example of a recording processing procedure focusing on the recovery processing, and FIGS. 3 (A) to 3 (D) are side views of the vicinity of the head unit and the cap in the processing, and FIG. The operation of the example will be described.

First, FIG. 3 (A) shows a state in which the power is turned off. A cap 3 is mounted on an orifice surface 12 provided with a discharge port of the recording head 1 to prevent evaporation of ink from the orifice. . The stationary position of the recording head 1 with the cap 3 mounted thereon is a capping position, which is set at a position higher than the surface of the transport belt 6 than a recording position described later.

In this state, when the power is turned on in step S1 of FIG. 2, the head unit is lifted by, for example, about 1 mm by the head moving means 24 in step S3 (FIG. 3B). In this state, when the idle ejection signal is supplied, the ink is ejected (idling) a predetermined number of times from all the nozzles (steps S5 and S7). This blanking is normally performed when the power is turned on and when about 100 sheets have been recorded by continuous paper feeding.If recording unevenness or the like occurs, the operator inputs a start signal by pressing a button. It may be configured to be able to do so.

Next, in step S9, the cap unit is moved in the direction opposite to the X direction by the cap moving means 25, and is placed at a position where the cap fits between the heads (FIG. 3 (C)). Then, in step S11, the head unit is lowered, and the ejection port is set to a position at a distance of, for example, about 1 mm from the belt surface, that is, a recording position (FIG. 3 (D)).

Next, in step S13, the paper feeding motor is turned on,
In response to this, the recording paper 27 in the cassette 26 is
It is picked up by 16, guided by a guide 13, and sandwiched between a transport roller 14 and a pinch roller 15. Recording paper 27
Is detected by a photo sensor or the like provided immediately before the resist section, and after the tip reaches the resist section,
After a predetermined time, the sheet feeding motor is turned off (step S15,
S17). At this time, the excess recording paper forms a loop in the space of the guide 13 formed in the shape of a mountain, and the leading edge of the recording paper is aligned with the resist part by the "strain", ensuring orthogonality with the transport direction. Is done.

Next, in step S19, the belt motor 8 and the charger 1
2 is turned on, and the recording paper 27 is guided between the chargers 12 while being pressed against the belt 6 by the pinch rollers 11a. Charger 12
For example, the belt 6 has a positive upper side and a negative lower side, and has a charge removed immediately before the pinch roller 11a.
A potential difference occurs between the recording paper 27 and the recording paper 27, and the recording paper 27 is attracted to the belt 6 by the electrostatic force. In addition, the pressure contact of the pinch roller 11b after passing through the charger makes this suction more reliable. On the other hand, the recording paper 27 is synchronized with the start of the belt motor 8.
Are fed, and printing (recording) of each color is performed when the leading edge of the recording paper reaches each of the recording heads 1a to 1d (step S21).

The recording paper 27 on which recording has been completed is separated from the belt 6 at the position of the belt driving roller 7 and discharged to the discharge tray 18. Then, after the end of paper ejection is detected in step S23,
In step S25, the belt motor 8 and the charger 12 are turned off.

Next, in step S27, it is determined whether a series of recording is completed.

If the next recording is not performed, the head unit is raised in step S29 (FIG. 3C), the cap unit is set in step S31 (FIG. 3B), and step S33 is performed. The head unit is put on at (FIG. 3 (A)), and the power is turned off at step S35.

If recording is to be performed on the next sheet of recording paper 27, the presence or absence of an idle ejection signal is detected in step S37, and if there is a signal, the head unit is raised in step S39 (see FIG. c)), the cap unit is set in step S41 (FIG. 3 (B)), and idle discharge is performed in step S43. Then, in step S45, the cap unit is returned (Fig. 3 (C)), and in step S47, the head unit is lowered to the recording position (Fig. 3 (D)). , The same recording sequence is repeated.

The present invention is, of course, not limited to the above-described components as long as it uses a linear recording head.

For example, in the above example, the number of recording heads is set to four in correspondence with the ink color, but the number is of course arbitrary.

In the above example, the ink is ejected by idle ejection as the recovery process. However, the ink may be ejected from the ejection port by pressurizing the print head or depressurizing the cap.

Further, in the above example, a belt and an electrostatic attraction member are used as the conveying means of the recording paper, but it goes without saying that other various methods such as an air attraction method using a belt and a method using a drum may be used. No.

In addition, in the above-described embodiment, the belt supporting member has a flat contact surface of the belt. However, the belt supporting member may have any shape as long as it does not adversely affect the adsorption of the recording paper to the belt. .

For example, as shown in FIG. 4, if the cross-sectional shape along the X direction is made convex, vibration can be more effectively suppressed.

[Effects of the Invention] As described above, according to the present invention, a member that supports a belt that sucks and conveys a recording sheet on the side opposite to the recording sheet surface at a position facing the recording head is provided. This suppresses belt vibration, prevents jams due to fluctuations in the head-paper gap, memory contamination due to contact between the recording head and recording paper, and does not promote deterioration of recording position accuracy due to ejection bending. High quality recording was realized.
Further, as described above, since the recording material is supported from the back surface by the support member, from the capping position at a position separated from the recording material mounting surface of the band member, the recording material is placed on the recording material mounting surface of the band member. Even if a plurality of liquid ejecting recording heads are integrally moved to a recording position close to each other, the recording material does not vibrate, so that the recording material does not contact any of the recording heads and a plurality of recording heads reach a predetermined proximity position. The recording can be executed by bringing the recording head close to the recording material.

According to the present invention, the plurality of cap members are
Since the liquid ejecting recording heads located at the recording position correspond to and are arranged adjacent to each other, the mutual movement distance between the recording head and the cap member can be suppressed short, and the size can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a configuration example of the liquid jet recording apparatus of the present invention, FIG. 2 is a flowchart showing an example of a recording processing procedure including an ejection recovery process by the configuration shown in FIG. 1, and FIGS. (D) is a side view for explaining the sequential operation of the movement of the recording head and the cap according to this embodiment, and FIG. 4 is a side sectional view showing another embodiment of the present invention. DESCRIPTION OF SYMBOLS 1 ... Recording head, 2 ... Recording head holder, 3 ... Cap, 4 ... Ink tank, 5 ... Ink supply tube, 6 ... Belt, 7 ... Belt drive roller, 8 ... Motor, 9 ... ... Idle roller, 10 ... Tension roller, 11 ... Pinch roller, 12 ... Charging device, 13 ... Guide, 14 ... Transport roller, 15 ... Pinch roller, 16 ... Paper roller, 17 ... Cleaning Unit, 18: Output tray, 19: Control circuit, 20: Head driver, 21: Motor driver, 22: Charger driver, 23: Motor driver, 24: Head moving means, 25: Cap moving means, 29 ... Support member.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-57-64260 (JP, A) JP-A-61-222751 (JP, A) JP-A-59-78877 (JP, A) JP-A-62 3954 (JP, A) JP-A-58-63451 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) B41J 11/02-11/13 B41J 13/08 B41J 13/22 B41J 2/165

Claims (1)

(57) [Claims] 1. A liquid jet recording apparatus for performing recording on a recording material by a plurality of liquid ejection recording heads arranged along a transport direction of the recording material, wherein the recording material is recorded by the liquid ejection recording head. A conveying unit having a band-shaped member for conveying to a possible area, and a band arranged on a portion of the band-shaped member corresponding to a back surface side of the recordable area on a recording material placement surface on which the recording material is placed. A support member for supporting the band-shaped member, and a position corresponding to each of the plurality of liquid jet recording heads located at the recording position and adjacent to a position separated from the recording material placement surface of the band-shaped member. A plurality of cap members, a plurality of liquid ejecting recording heads, and a recording position for executing recording on the recording material in proximity to the recording material mounting surface of the band-shaped member; And a head moving means for integrally moving the head to a capping position where the liquid is ejected.