JP2000289908A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device that can detect use of rolled recording media, and their remaining amount, end of use and thickness. SOLUTION: A shaft 19 has at one end a detection disk 21 which has a plurality of slits 21a and whose center receives the shaft 19 that passes through it. A light emitting part 22a on an optical sensor 22 emits light L1 onto the detection disk 21, and a light receiving part 22b receives the reflected light L2. This expedient can detect the rotation, and angular velocity ω of rolled recording media, and thus can set them properly for printing and detect their remaining amount and end of use.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image forming apparatus provided with a recording medium detecting device during conveyance of a roll-shaped recording medium used in the image forming apparatus.

[0002]

2. Description of the Related Art A recording device such as a printer, a copying machine, a facsimile or the like, or a recording device used as an output device such as a computer, a word processor, a work station or the like, is based on image information and is formed of recording paper or plastic thin plate (OHP paper or the like) ) Is configured to record an image (including characters and symbols) on a recording medium. The recording apparatus may be an ink jet type, a wire dot type, a thermal type, a thermal transfer type,
There is a laser beam type and the like.

In a serial type recording apparatus employing a recording method in which a main scanning is performed in a direction intersecting with a conveying direction (sub-scanning direction) of the recording medium, the recording medium is set at a predetermined recording position and then moved along the recording medium. An image (including characters and symbols) is recorded by recording means (recording head) mounted on a moving (main scanning) carriage, and after one line of recording is completed, a predetermined amount of paper feed (sub-scan) is performed. After that, the operation of recording (main scanning) the image on the next line is repeated, whereby the image is recorded in a desired range of the recording medium.

[0004] As a form of a recording medium (media) used in the above-described ink jet recording apparatus, a recording medium cut into individual sheets (hereinafter referred to as a cut medium) and a roll form are taken up. Recording media (hereinafter referred to as roll media), and these are properly used depending on the application.

[0005]

However, in the prior art, there are the following problems when using the above-described media properly.

(1) When switching from a cut medium to a roll medium or from a roll medium to a cut medium, an operation for designating a medium to be used is required in advance. If this operation is forgotten or incorrectly specified, the recording medium may not be set normally.

(2) When a roll medium is used, the type of the medium to be used is changed depending on the application, and printing may be performed with the setting of the medium to be used being incorrect.

(3) When a roll medium is used, the remaining printable number cannot be known unless the remaining amount of the medium is known, and the medium may run out during printing.

(4) When a roll medium is used, the end of use of the medium has been detected by an optical sensor provided near the platen, a microswitch provided in the middle of the transport path, or the like. However, with optical sensors,
In some cases, the sensitivity may be lowered due to the adhesion of the mist ink, or the media may be damaged by the measurement pressure of the microswitch.

Accordingly, an object of the present invention is to provide an image forming apparatus capable of detecting the use of a roll medium, detecting the end of use of the roll medium, and detecting the thickness of a recording medium.

[0011]

According to a first aspect of the present invention, there is provided an image forming apparatus in which at least one of a sheet recording medium and a roll recording medium is mounted. The apparatus includes a rotation detecting unit that detects the rotation of the recording medium, and a determining unit that detects a form of the mounted recording medium based on a detection result by the rotation detecting unit.

Further, in the invention according to the second aspect, the determining means according to the first aspect has a function of detecting the thickness of the roll-shaped recording medium by detecting the rotational angular velocity of the roll-shaped recording medium. are doing.

Further, in the invention according to claim 3,
The determining means according to the first aspect has a function of detecting the remaining amount of the roll-shaped recording medium by detecting the rotational angular velocity of the roll-shaped recording medium.

Further, in the invention according to claim 4, the determining means according to claim 1 has a function of detecting the end of the roll-shaped recording medium.

According to the first aspect of the present invention having such a configuration, the type of the inserted recording medium is automatically determined without prior designation, and the optimum setting method for the type is set. Is automatically selected.

According to the second aspect of the present invention, the type of the mounted roll-shaped recording medium is specified from the detected thickness of the roll-shaped recording medium, and the setting of the medium to be used is mistaken. It can be printed without.

Further, according to the third aspect of the present invention, the remaining amount of the medium is grasped and a warning or the like is accurately issued.

According to the fourth aspect of the present invention, the end of use of the medium can be detected without soiling or damaging the medium.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of an image forming apparatus according to the present invention will be described in detail with reference to the drawings. Prior to this, an ink jet plotter suitable for applying the present invention (hereinafter referred to as a plotter) will be described. Will be described as an example.

In the plotter shown in FIG. 1, a carriage 4 is supported by a guide shaft 5 located above a platen 6 via a slide bearing (not shown), and is guided by a carriage motor and belt (not shown). 5 is provided so as to be reciprocally movable in the directions of arrows A and B (width direction) in the figure.

A recording means (recording head) 3 is mounted on the carriage 4, and the carriage 4 is configured to be able to reciprocate in the directions of arrows A and B in the drawing. The recording head 3 is a replaceable cartridge type in which an ink ejection unit and an ink tank are integrated,
It is electrically connected to a later-described control device 9 provided in the device main body via a flexible cable or the like (not shown).

A cleaning unit 7 is provided at a retracted position outside the image forming area at one end of the movable range of the carriage 4, and the cleaning unit 7 has a wiping operation, which is an ejection recovery process of the recording head 3. And a negative pressure generating means such as a wiper blade (not shown) for performing a preliminary discharge operation and a suction operation, a cap, and a pump for a suction operation.

A control device 9 for controlling the plotter is provided on the side opposite to the cleaning unit 7 with the carriage 4 interposed therebetween. The control device 9 controls an image signal carrying image information, and based on the image signal transmitted from the control device 9, discharges ink to the recording medium (media) P of the recording head 3, which will be described later. It has a function of controlling the transport timing and transport amount of the recording medium P by the transport roller 10, a determination function of detecting the type of the set recording medium, and the like.

An opening is provided on the platen 6 on which the recording medium P is placed. From the opening, a part of the outer peripheral surface of the conveying roller 10 is exposed. Pinch rollers 8 are provided at both ends in the width direction on the downstream side so as to press the recording medium P from above.
The transport roller 10 and the pinch roller 8 are configured to pinch and transport the recording medium P on the platen 6.

Upstream in the transport direction of the plotter (left side in FIG. 1)
As shown in FIGS. 2A and 2B, an insertion slot 1 for horizontally inserting the recording medium P is provided. A roller 2 is provided. Thereby, the roll media (roll-shaped recording medium) 17 or the cut media (sheet-shaped recording medium) 1
8, a recording medium P is inserted through the insertion slot 1 and conveyed onto the platen 6 by the paper feed roller 2.

As shown in FIG. 2C, the roll medium 17 is composed of a recording medium P and a cylindrical core 17a serving as a winding core of the recording medium P.
The roll shaft 19 is inserted into the cylinder of
The core 17a is provided by holders 20 provided at both ends of the core 17a.
Are fixed to a roll shaft 19, and both end portions of the roll shaft 19 are rotatably supported and set below the insertion slot 1.

When the roll medium 17 is mounted, as shown in FIG.
The leading end of the recording medium P unwound from the insertion slot 1
2 and in the case of the cut media 18, FIG.
As shown in (b), each recording medium P is inserted from the insertion slot 1 and conveyed onto the platen 6 by the paper feed roller 2.

On the recording medium P conveyed onto the platen 6 as described above, an image of one line is recorded by the recording head 3 in the directions of arrows A and B in FIG. After that, the transport roller 10 and the pinch roller 8 are moved in a direction (transport direction) orthogonal to the directions of arrows A and B in the figure.
And conveyed by one line. The printing of one line of the image and the conveyance of the one line are alternately performed until the predetermined printing is completed.

FIG. 3 is a main part configuration diagram for explaining an embodiment of the image forming apparatus according to the present invention. In the embodiment shown in FIG. 3, a detection disk 21 is fixed to one end of a roll shaft 19 that supports the roll media 17 described above. The roll shaft 19 passes through the center of the detection disk 21 together with the roll medium 18, and the detection disk 21 is arranged so as to face the axial end surface of the roll medium 18. This detection disk 2
1, a plurality of elongated slits 21a extending radially from the center side are formed to open. The plurality of slits 21a extend in the radial direction from near the center of the detection disk 21 and are arranged at substantially equal intervals in the circumferential direction.

Further, an optical sensor 22 is attached to the detection disk 21 at a predetermined interval so as to face the side surface of the detection disk 21. This optical sensor 2
Numeral 2 is disposed so as to face the detection disk 21, and a light emitting unit 22a and a light receiving unit 22b are provided on the facing surface. Then, the detection light L1 emitted from the light emitting unit 22a is applied to the detection disk 21 and reflected light L2 from a surface of the detection disk 21 other than the slit 21a is received by the light receiving unit 22.
b.

That is, although the reflected light L2 is not obtained from the slit 21a and the reflected light L2 is obtained from the disk surface other than the slit 21a, the reflected light L2 is input to the light receiving portion 22b. The rotation state of the detection disk 21 is detected based on the presence or absence.
The detection result is sent to the control device 9 as a detection signal, and is configured so as to control the conveyance of the recording medium P and to issue an alarm at the time of abnormality as described later. The number and size of the slits 21a provided in the detection disk 21 are optimal according to the detection content and the like described later.

When the roll medium 17 is set, the roll medium 17 is set as described above.
The recording medium P unwound from the recording medium P is conveyed by the paper feed roller 2, and the roll medium 17 rotates accordingly, and the detection disk 21 rotates in synchronization with the roll medium 17. The detection light L1 is emitted from the light emitting part 22a of the optical sensor 22 to the detection disk 21 in the rotating state.
1a crosses periodically in accordance with the number of rotations. Then, the reflected light L2 is periodically interrupted in accordance with the cycle traversed by the slit 21a.
Then, by detecting the interruption of the reflected light L2, the rotation state of the detection disk 21 is detected.

The control device 9 includes the detection disk 2
A discriminating means for detecting the state of the recording medium and the like by detecting the rotation state of the roll medium 17 using No. 1 is provided. The contents of a control program for performing the discriminating function will be described below.

First, the paper feed roller 2 rotates and the recording medium P
Is being conveyed, the light receiving unit 22b outputs the reflected light L2.
The detection and non-detection are repeated, and accordingly, as shown in FIG.
If it is detected that (9) is rotating (YES in step 1 in FIG. 4), it is known that the roll medium 17 is used as the recording medium P at that time (see step 3 in FIG. 4). . On the other hand, the light receiving portion 22b is provided with
If the detection disk 2 (the shaft 19) is not rotating (NO in step 1 in FIG. 4), the recording medium P at that time is cut. It can be seen that the media 18 is being used (see step 2 in FIG. 4).

When such a detection signal is sent to the discriminating means in the control device 9, the roll media 1
Whether the media 7 or the cut media 18 is used is automatically determined based on the control program provided in the control device 9 described above, and is used for transport control of the recording medium P.
In the case where only the form of the recording medium P is determined in this way, it is only necessary to know the rotation / non-rotation of the disk, so the number of slits 21a and the sensitivity of the optical sensor 22 may be configured to be relatively low. .

At this time, the diameter of the roll medium 17 gradually decreases as the recording medium P continues to be used. On the other hand, since the recording medium P is being conveyed at a constant speed, the diameter of the roll medium 17 is small. As the rotation speed becomes smaller, the rotation speed of the roll media 17 increases. That is, assuming that the conveying speed of the recording medium P is v, the radius of the roll medium 17 about the rotation axis is r, and the rotation angular velocity is ω, the following relationship is established. v = rω Here, ω is detected by the optical sensor 22, and since the transport speed v is constant, the radius r of the roll media 17 is
It can be calculated by r = v / ω.

Therefore, if the number of times of detection of the reflected light L2 per unit time from the rotating detection disk 21 per unit time (or the number of times the reflected light L2 is interrupted) is known, the slit 21a
Are constant, the angular velocity ω of the detection disk 21, that is, the roll medium 17 is known, and thus the radius of the roll medium 17 is known. Slit 21 in this case
Since the number of a and the sensitivity of the optical sensor 22 need to know the angular velocity of the disk, it is preferable that the sensitivity is relatively high.

Further, if the rate of change of the angular velocity ω of the roll medium 17 is known, the amount of change in the radius r of the roll medium 17 can be determined. (See step 4 in FIG. 4).

Here, the thickness of the recording medium P used in the roll medium 17 differs depending on applications such as text printing, graphic printing, and photographic quality printing. Therefore, by setting the use recording medium P for each use in advance based on the thickness, when a print mode different from the use of the recording medium P is set (NO in Step 5 in FIG. 4),
It is configured to output an alarm that the setting is incorrect (see step 6 in FIG. 4).

As described above, the radius of the currently set roll medium 17 can be known, so that the detected radius r of the roll media 17 and the radius r1 of the roll media 17 when not in use are determined. Core radius r
2, the remaining amount of the recording medium P on the roll medium 17 can be known (see step 7 in FIG. 4). When the rotation of the roll medium 17 is no longer detected, the use of the recording medium P is stopped. You can know the end (Fig. 4
Step 8).

Although the embodiments of the present invention made by the inventor have been specifically described above, the present invention is not limited to the above-described embodiments, and can be variously modified without departing from the gist thereof. Needless to say. For example, the sensor for detecting the rotation of the roll media 17 is not limited to the optical sensor 22, and other sensors such as a linear sensor may be used as long as the sensor can detect the rotation of the roll media 17. The good thing goes without saying.

[0042]

As described above, the invention according to claim 1 has rotation detecting means for detecting the rotation of the roll-shaped recording medium, and forms the recording medium based on the detection result by the rotation detecting means. Is determined, the form of the inserted recording medium is automatically determined without prior designation, and the optimal setting method for that form is automatically selected.

Further, the invention described in claim 2 is the same as the claim 1.
The thickness of the roll-shaped recording medium is detected by detecting the rotational angular velocity of the roll-shaped recording medium by the rotation detecting means described in (1), and the setting of the medium to be used is incorrect depending on the thickness. Can be printed without the need.

According to a third aspect of the present invention, the remaining amount of the roll-shaped recording medium is detected by detecting the rotation angular velocity of the roll-shaped recording medium by the rotation detecting means of the first aspect. Thus, the remaining amount of the media can be accurately grasped.

Further, the invention described in claim 4 is the same as that in claim 1.
Since the end of the roll-shaped recording medium is detected by the rotation detecting means described in (1), the end of use of the medium can be detected without soiling or damaging the medium.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of an inkjet blotter to which an image forming apparatus according to the present invention is applied.

FIG. 2 is a configuration diagram of a main part of the inkjet blotter illustrated in FIG. 1;

FIG. 3 is a main configuration diagram for explaining an embodiment of an image forming apparatus according to the present invention.

FIG. 4 is a flowchart for explaining the operation of the embodiment shown in FIG. 3;

[Explanation of symbols]

 Reference Signs List 1 insertion slot 2 paper feed roller 3 recording head 4 carriage 6 platen 17 roll media 17a core 18 cut media 19 shaft 21 disk 21a slit 22 optical sensor P recording medium

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2C060 BA04 BA10 BC95 2C061 AP02 AP03 AP04 AQ05 AS06 AS13 LL01 LL04 LL06 3F105 AA02 AB01 AB02 AB04 BA22 DA17 DA32 DA51 DA55 DB11 DC13 5C062 AA05 AB08 AB09 AC58 AC65 AC68 BA04

Claims (4)

[Claims] 1. An image forming apparatus in which at least one of a sheet-shaped recording medium and a roll-shaped recording medium is mounted, rotation detecting means for detecting rotation of the roll-shaped recording medium, and a rotation detecting means for detecting rotation of the recording medium. And a determining means for detecting the form of the loaded recording medium. 2. An image forming apparatus according to claim 1, wherein said determining means has a function of detecting a thickness of the roll-shaped recording medium by detecting a rotation angular velocity of the roll-shaped recording medium. 3. An image forming apparatus according to claim 1, wherein said determination means has a function of detecting a remaining amount of the roll-shaped recording medium by detecting a rotation angular velocity of the roll-shaped recording medium. 4. An image forming apparatus according to claim 1, wherein said determining means has a function of detecting the end of the roll-shaped recording medium.