JPH01275351A - Recording device - Google Patents

Abstract

PURPOSE:To detect transfer errors and size errors of record sheets in an ink jet type record device for recording under the fixedly sucked condition of the record sheet by detecting pressure of a platen for sucking and holding the record sheet. CONSTITUTION:When a suction pump 6 is driven to input a record starting signal to a controller 15 after a record sheet 1 is supplied, a pair of transfer rollers 3a-3d are driven by a specified amount and stopped after transferring the record sheet 1 to a record position. Then, a pressure sensor 8 detects suction pressure in a platen 4. When the record sheet 1 of set size is adsorbed properly, the pressure in the platen 4 is reduced to a specified value corresponding to the size. If the record sheet 1 is skewed, sized smaller than the specified size or damaged, the suction pressure is not reduced to the specified value. If it is exceeds the set size, the suction pressure is reduced less than the specified value. Thus, if the suction pressure does not show the specified value, the drive of the pump 6 is stopped to indicate abnormal transfer of the sheet 1 on an indicating section.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a recording device that performs recording with a recording sheet fixed by suction, and more specifically, the present invention relates to a recording device that performs recording with a recording sheet fixed by suction, and more specifically, detects the state of the recording sheet by detecting the suction pressure. The present invention relates to a recording device capable of recording.

<Prior Art> Today, various recording devices have been developed, and among them is an inkjet type recording device. For example, in the case of a serial type recording device, the recording sheet is conveyed to the recording section by a conveyance means and fixed therein, and an inkjet type recording head is run in the width direction of the recording sheet.
A predetermined ink image is recorded on a recording sheet by ejecting ink from the head.

In the recording apparatus, a suction platen is generally provided in the recording section to fix the recording sheet to the recording section, and the platen suctions and holds the recording sheet according to its size.

<The invention tries to solve i! l! a> In the above device, since the recording sheet is suctioned by the platen according to the size of the sheet, when the recording sheet is conveyed, the recording sheet may be skewed or partially damaged. When the recording sheet is conveyed, the suction area by the platen is no longer entirely covered with the recording sheet, and a portion of the suction area is exposed. As a result, the suction pressure decreases, making it impossible to bring the recording sheet into close contact with the platen, making it impossible to record a normal image with the recording head, or ejecting ink onto the exposed suction area of the platen. This may stain the platen.

The above problem becomes particularly noticeable when the recording sheet is manually fed to the recording section.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional problems and to provide a recording apparatus that can detect recording sheet conveyance errors and recording sheet size errors.

<Means for Solving the Problem> In order to achieve the above object, in a recording device that performs recording with a recording sheet fixed by suction, a platen for suctioning and holding the recording sheet, and a platen for suctioning and holding the recording sheet, and a The present invention is characterized in that it includes a recording means for recording on a recording sheet, a suction means for applying suction pressure to the platen, and a detection means for detecting the suction pressure.

Effect> According to the above means, when the recording sheet is suctioned and held by the platen, the suction pressure of the platen changes due to skewing of the recording sheet, missing parts, etc. Therefore, by detecting the suction pressure with the detection means, a recording sheet conveyance error or the like can be detected.

<Embodiment> Next, an embodiment of a recording apparatus in which the above means is applied to a serial type inkjet recording method will be described with reference to the drawings.

[First example]

FIG. 1 is an explanatory cross-sectional view of an inkjet recording apparatus, and FIG. 2 is a perspective explanatory view of the main parts.

In the figure, l denotes a long recording sheet i, in which a sheet roll 1a wound into a roll is loaded into a holder 2, and the recording sheet l is transported by a pair of transport rollers 3a driven and rotated by a motor. , 3b, 3c, 3d by arrow a
It is intermittently conveyed in the direction.

Furthermore, a platen 4 is provided at a predetermined position on the conveyance path of the recording sheet 1 with the recording sheet 1 in between,
A recording head 5 constituting recording means is provided on the other side.

The platen 4 suction-holds the conveyed recording sheet 1, and is composed of a hollow casing, has a large number of suction holes 4a perforated in the suction surface of the recording sheet 1, and has an end portion of the platen 4. has a suction pipe 7 connected to a suction pump 6.
is connected.

Therefore, when the suction pump 6 operates, the recording sort I is suctioned through the suction hole 4a of the platen 4 and is suctioned and held on the surface of the platen 4.

Furthermore, a pressure sensor 8 for detecting the suction pressure within the platen 4 is provided at a predetermined position of the suction pipe 7.
The sensor 8 is connected to a control section which will be described later.

Therefore, when the pump 6 operates, the pressure inside the platen 4 is detected by the sensor 8, the detection result is transmitted to the control section, and a predetermined display is displayed on the display section according to a signal from the control section. It is something.

On the other hand, the recording head 5 has an ink shared nozzle that can selectively eject ink in response to both signals, and an ink chamber communicating with the nozzle.
It is mounted on a carriage 10 that can reciprocate along a rail 9 provided parallel to the . As shown in FIG. 2, the carriage 10 includes a belt 11 and pulleys 12a, 1.
It is connected to a carriage motor 13 via 2b, and is movable by driving the motor 13.

In FIG. 1, 14 is a cutter for canting the recording sheet I, and 5a is a head cap that covers the recording head 5 when not recording.

Next, to explain the control system of the device having the above configuration, as shown in the pronk diagram of FIG. Along with being used as an area,
A control unit 15 including a RAM 15c for temporarily storing various data, an interface 1G, an operation panel 17,
Each motor (carriage motor 13, transport motor 18 for driving the transport roller pair, cutter motor 19 for driving the counter 14), suction pump 6, and drivers 20a to 20 for driving the recording head 5.
A preamplifier 21 and A for amplifying and digitizing the signal from the C1 pressure sensor 8 and transmitting the digitized signal to the control unit 15
The display unit 23 includes a /D converter 22 and a display unit 23 that performs predetermined display based on signals from the control unit 15.

The control unit 15 receives various information (for example, recording density, number of recording sheets,
(recorded size, etc.), and input an image signal from the external device 24. The control unit 15 also has an interface 16.
Motor ON to drive each motor via
It outputs an OFF signal, an ON/OFF signal for the suction pump 6, and an image signal, and each member is driven by the signals.

Next, the operation when performing recording using the recording apparatus having the above-described configuration will be described.

As shown in the flowchart of FIG. 6, after feeding the recording sheet 1, the suction pump 6 is driven (Sl), and when the control unit 15 inputs a recording start signal in this state, the conveying roller pairs 3a to 3d move by a specified amount. The recording sheet 1 is driven to be conveyed to the recording position and stopped (32.S3). At this time, the pressure sensor 8 detects the suction pressure inside the platen 4 (3
4) When the recording sheet 1 of the set size is properly adsorbed, the pressure inside the platen 4 decreases to the specified value according to the size, but if the recording sheet 1 is skewed or the size is smaller than the set size, Alternatively, if it is missing, the suction pressure will not decrease to the specified value because it will not come into close contact with the platen 4 properly. Furthermore, if a recording sheet 1 of a size larger than the set size is conveyed, the suction pressure will drop below the specified value. It can be determined whether the recording sheet 1 has been properly conveyed and attracted.

Therefore, if the suction pressure is large to the specified value, the driving of the suction pump 6 is stopped and a message indicating that the conveyance state of the recording sheet (1) is abnormal is displayed on the display section 23 (84 to S6).

On the other hand, if the suction pressure is the specified value (iα), the process moves to step S7 and subsequent steps to perform normal ink-end recording (37 to 5ll).

As described above, if there is a conveyance error or size error of the recording sheet 1, a warning is issued to prevent defective recording and staining of the platen 4 with ink.

(Second Embodiment) FIG. 5 shows another embodiment in which the suction pressure within the platen 4 is detected.

In the figure, 25 is a suction pump using a DC motor that communicates with the platen 4 as in the first embodiment.
are voltage follower amplifier 26, preamplifier 27, A
/D converter 2 is connected to the control unit 29 in order. Further, 30 is a transistor for driving the pump 25, and 31 is a current limiting resistor of the pump 25.

Even in the above configuration, the recording sheet l is the same as in the first embodiment.
If the suction state is abnormal when the pump 25 is attracted to the platen 4, the load when operating the pump 25 is different from that when the load is appropriate, and this appears as a change in the value of the current flowing through the resistor 31. Therefore, by detecting the change as a voltage value change at point A in FIG. 5 by the control unit 29 via the amplifiers 26, 27, etc., it is possible to detect a conveyance error or a size error of the recording sheet l. be.

<Effects of the Invention> As described above, the present invention can detect conveyance errors, size errors, etc. of the recording sheet by detecting the pressure of the platen that sucks and holds the recording sheet. etc. can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional explanatory diagram of a recording apparatus according to an embodiment of the present invention, FIG. 2 is a perspective explanatory diagram of main parts, FIG. 3 is a block diagram of a control system, FIG. 4 is a flowchart of recording operation, and FIG. The figure is an explanatory diagram of another embodiment. 1 is a recording sheet, 1a is a sheet roll, 2 is a holder,
3a to 3d are transport roller pairs, 4 is a platen, 4a is a suction hole, 5 is a recording head, 6 is a suction pump, 7 is a suction pipe, 8
is a pressure sensor, 9 is a rail, 10 is a carriage, 11
is a belt, 12a and 12b are pulleys, 13 is a carriage motor, 14 is a cutter, 15 is a control unit, and 15a is C
PU, 15b is ROM, 15c is RAM, 16 is interface, 17 is TI panel, 18 is transport motor, 19 is cutter motor, 20a to 20e are drivers, 21 is preamplifier, 22 is A/D converter, 23
24 is a display unit, 24 is an external device, 25 is a suction pump, 26.
27 is an amplifier, 28 is a converter, 29 is a control unit, 30
is a transistor, and 31 is a resistor.

Claims (1)

[Claims] A recording device that performs recording with a recording sheet fixed by suction, comprising: a platen for suctioning and holding the recording sheet; and a recording means for recording on the suction-held recording sheet. A recording apparatus comprising: a suction means for applying suction pressure to the platen; and a detection means for detecting the suction pressure.