JPH03290263A - Ink jet recording device - Google Patents

Abstract

PURPOSE:To obtain multi-step resolution and speed up and recording time by making an angle of nozzle arrangement variable with respect to the carrying direction of a recording paper. CONSTITUTION:By a resolution mode command, an angle indicating signal for a head 11 is input in an angle driving circuit 13, and the angle is set. At the same time, a recording paper carrying quantity and carriage speed are respectively set by a recording paper carrying quantity setting unit 16 and a carriage speed setting unit 15. Since the angle for nozzle arrangement is variable, picture with high density which is not less than the actual nozzle arrangement pitch can be obtained. Also, when fast recording performed at a low resolution, by changing the arrangement angle, it can be coped with by one head without using thinning printing or making the head unnecessarily large. Accompanying with the angle variation, the carriage speed is changed, and many types of dot patterns can be obtained by combinations of both parts.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to an inkjet recording apparatus, and more particularly to a head section of an on-demand type inkjet recording apparatus.

Prior Art Publicly known documents describing the prior art related to the present invention include:
There is Japanese Unexamined Patent Publication No. 54-32321. The difficulty is that a plurality of unit orifice rows having a plurality of orifices drilled at minute intervals are arranged in parallel at an angle of O to the moving direction of the recording medium, and the orifice opening position in each unit orifice row is A configuration is disclosed in which unit orifice rows are arranged so as not to overlap in the moving direction. Further, in a conventional on-demand inkjet head, a plurality of nozzles are arranged at an angle with respect to the moving direction of the recording medium with respect to the carriage running direction, and the angle is fixed.

As described above, the conventional on-demand inkjet head uses a piezoelectric body or a heater as an actuator to eject ink by changing the volume of the liquid chamber. The device to obtain the energy for ejecting requires a certain size of drive source, and on top of that, there are limits to achieving high resolution due to processing. In order to improve these drawbacks, attempts are being made to improve the effective printing pitch relative to the actuator pitch by arranging the nozzle array at an angle with respect to the recording medium.

1-2- However, in the conventional technology, since the angle is fixed, there is no degree of freedom regarding the resolution.

That is, even if the nozzle and actuator section are made with a resolution of 100 dpi (dots/inch), by creating a 60° slope in the conveying direction of the recording paper, an effective printing resolution of 100/cos 60° and 200 dpi can be obtained. However, since the angle is fixed, when printing in high-speed mode, only the * mark in each image is used for printing, as shown in Figure 6, and when printing at a resolution of 100 dpi. The carriage speed was doubled, and the time to print the entire recording sheet was only halved.

Purpose The present invention was made in view of the above-mentioned circumstances.
The purpose of this invention is to provide an inkjet recording device that can obtain multi-stage resolution from a fixed-resolution inkjet printer and speeds up the recording time.

Configuration In order to achieve the above object, the present invention provides the following features: (1) 3- In an on-demand inkjet recording device having a plurality of nozzles, the angle of the nozzle array is made variable with respect to the conveying direction of recording paper; (2) changing the angle of the nozzle array with respect to the print information, and varying either the conveyance amount of the recording paper or the carriage speed, or both; and (3) changing the angle of the nozzle array with respect to the print information; In contrast, the present invention is characterized in that it includes a drive circuit that changes the angle of the nozzle array and changes the amount of ink ejected. Hereinafter, the present invention will be explained based on examples.

FIG. 10 is a plan view for explaining one embodiment of the nozzle arrangement of the ink shed recording apparatus according to the present invention.
is the nozzle and 0 is the pitch of the nozzle. Nozzle 1 is Q
They are arranged in pitches of length. If this is tilted by θ, the pitch actually printed will be 12 cos θ.

Figure 2 shows the inclination angle (0) of the nozzle array and the resolution ratio (α
= Q / A cosA ). For example, by setting 0 = 60° in the initial state and setting this as the normal 4-normal density, by tilting θ = 75°, that is, 5 + 15°, β = Q cos 75° / +2cos60″42.0 allows printing with double density as final mode.Also,
On the other hand, by tilting the printer by -30' from the initial state, it is possible to print in draft mode with 8 lines of 0.57 and approximately half the density.

FIG. 3 is a block diagram of the recording section of the inkjet recording apparatus according to the present invention, in which 11 is a head, 12 is an actuator drive circuit, 13 is an angle drive circuit, and 14 is a CPt.
J (central processing unit), 15 is a carriage speed setting section,
16 is a recording paper conveyance amount setting section. An angle designation signal is input to the angle drive circuit 13 of the head 11 in response to a resolution mode command, and the angle is set. At the same time, the recording paper conveyance amount and carriage speed are also set by the recording paper conveyance amount setting section 16 and the carriage speed setting section 15, respectively.

FIG. 4 is a diagram showing an example of a printing pattern according to the present invention.
Figure (a) is a standard printing pattern, that is, when the inclination angle θ of the nozzle array is 45°, and the carriage speed and recording paper conveyance amount are standard. Figure (b) shows the printing pattern in the final mode when the nozzle array inclination angle θ is +15° and the carriage speed and recording paper transport amount are -35%. Although the recording speed per sheet is -35%,
Very detailed images can be obtained. Figure (c) shows the printing pattern in draft mode when the nozzle array inclination angle θ is -15° and the carriage speed and recording paper transport amount are +35%.The pixel density decreases, but the recording speed increases. It is possible to record at a speed approximately 2.3 times faster than the standard. Figure (d) is vertical file, horizontal standard, and figure (e)
shows the printing pattern when only the inclination angle O of the nozzle arrangement is changed and the carriage speed is set as the standard for both vertical draft and horizontal standard. Furthermore, various patterns can be easily obtained by adjusting the inclination angle θ of the nozzle arrangement and the setting level of the carriage speed. Furthermore, by combining the actuator's driving force, ejection amount, and dot diameter, an even more precise image can be obtained.

FIG. 5 is a diagram showing an example in which the actuator driving force is changed in order to compensate for the blank portion that appears in FIG. 4 (Q) in the draft mode.

Effects As is clear from the above explanation, the present invention has the following effects.

(1) Since the angle of the nozzle array is variable, an image with higher density than the actual nozzle array pitch can be obtained. Also, when recording at low resolution and at high speed, by changing the arrangement angle, one head can be used without the conventional thinning printing or an unnecessarily large head.

(2) The carriage speed is changed in accordance with the angle change in (1) above, and various dot patterns can be obtained by combining the two.

[Brief explanation of the drawing]

FIG. 1 is a plan view for explaining one embodiment of the nozzle arrangement of an inkjet recording apparatus according to the present invention, and FIG.
A diagram showing the relationship between the inclination angle (θ) of the nozzle array and the resolution ratio, FIG. 3 is a block diagram of the recording section of the inkjet recording apparatus according to the present invention, and FIGS. FIG. 5 is a diagram showing an example of a printing pattern according to the invention; FIG. 5 is a diagram showing a printing pattern when the driving force of the actuator is changed in draft mode; FIG. 6 is a diagram showing a conventional example when the angle is fixed. be. DESCRIPTION OF SYMBOLS 1... Nozzle, 11... Head, 12... Actuator drive circuit, 13... Angle drive circuit, 14...
・CPU, 15... Carriage speed setting section, 16...
- Recording paper conveyance amount setting section. 7- (a) Standard carriage scanning direction (b) Final mode (C) Draft mode Vertical final (d) Horizontal standard (e) Vertical draft horizontal standard Diagram

Claims (1)

[Scope of Claims] 1. An on-demand inkjet recording device having a plurality of nozzles, characterized in that the angle of the nozzle array is variable with respect to the conveyance direction of recording paper. 2. An inkjet recording apparatus characterized in that the angle of the nozzle array is changed with respect to print information, and either or both of the conveyance amount of the recording paper and the carriage speed are made variable.