JPH0558012A - Image recording device - Google Patents

Abstract

PURPOSE:To prevent platen hitting from happening, and keep the surfaces on the platen side of a device or recording medium clean by deciding the carrying condition of a recording medium to be favorable or not, based on signals by a paper width detecting means. CONSTITUTION:By a recording start command, a recording medium is sent out from a cassette by pick-up rollers. When it is decided that there is a recording medium by a paper feed sensor, the recording medium is fed by a pair of paper feed rollers by respective necessary paper feed quantities C, D at the time of a leading end/rear end mode and normal mode. Then, when it is decided that there is a recording medium by a paper delivery sensor, detecting motion for a paper width and paper type is performed by moving a carriage in the paper width direction, and the paper type is decided based on a signal pattern which is obtained by a paper width sensor. When it is decided that the recording medium has not reached a specified position on a platen by a signal pattern, the generation of jamming is informed, and being a coated paper, a clear sheet for OHP is decided, and also it is decided that abnormality is generated on the paper width sensor, platen or carriage, etc.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image recording apparatus for recording an image on a recording medium.

[0002]

2. Description of the Related Art In a conventional image recording apparatus such as an inkjet recording apparatus, a pair of recording media such as a recording sheet and a clear sheet for OHP are provided on the upstream side of the platen with respect to the transport direction along which the recording medium is fed along the platen. A sheet feeding unit including a roller and the like is installed, and a sheet discharging unit including a pair of rollers and the like is installed on the downstream side of the platen.
Further, a paper feed sensor and a paper discharge sensor for detecting the presence / absence of a recording medium are installed near the paper feed means and near the paper discharge means, respectively. In a carriage that reciprocates in a direction perpendicular to the transport direction (hereinafter referred to as "paper width direction") between a paper feeding unit and a paper discharging unit, a recording head has a predetermined size with respect to a recording medium on a platen. They are mounted so that they face each other with a gap in between. Further, a paper width sensor is installed in the vicinity of the recording head of the carriage, and this paper width sensor reads the difference between the amount of reflected light from the platen and the amount of reflected light from the recording medium as the carriage moves. The width of the recording medium (hereinafter referred to as "paper width") and the type of recording medium (hereinafter referred to as "paper type") are detected.

Next, a method of controlling such an ink jet recording apparatus will be described.

First, from the position where the front end of the recording medium is detected by the paper feed sensor provided on the upstream side of the platen,
The recording medium is fed by the paper feeding means along the platen in the conveying direction by a predetermined paper feed amount required for the leading end of the recording medium to reach the paper discharge means. Here, the presence or absence of the recording medium is checked by the paper discharge sensor provided on the downstream side of the platen,
When it is detected that the recording medium is absent, it is determined that the recording medium has not reached the sheet discharging means, and the jam is notified. When the discharge sensor detects that the recording medium is present, it is determined that the recording medium has normally reached the discharge unit, and the carriage is moved to detect the paper width and the paper type. After that, the recording operation is started. The above is the normal mode.

In the normal mode, since there is a distance from the tip of the recording medium to the position where the recording head records,
A large blank area where no recording is performed is formed at the leading end of the recording medium. Therefore, a front / rear edge mode has been proposed in which recording is performed from a position immediately near the front end of the recording medium without taking a large margin.

FIG. 20 is a flowchart of the front / rear end mode. The conventional front / rear end mode will be described with reference to this drawing.

First, the recording medium is fed toward the platen by the sheet feeding means, and in step S2A, it is determined by the sheet feeding sensor whether or not the front end of the recording medium reaches the sheet feeding sensor. If it is detected that the paper feed sensor is absent, the process proceeds to step S3A to continue feeding. When it is detected that the paper feed sensor is present, the process proceeds to step S4A, and the recording medium is fed to the platen by the paper feeding means by a predetermined paper feed amount A required for the leading edge of the recording medium to exceed the recording position of the recording head. And send in the transport direction. Next, in step S5A, the carriage is moved in the paper width direction, and the paper width sensor detects the paper width and paper type. In step S6A, the paper type is determined based on the signal pattern obtained by the paper width sensor. When it is determined that the paper width sensor is abnormal, the process proceeds to step S61A to notify the abnormality of the paper width sensor, when it is determined that the sheet is an OHP clear sheet, the process proceeds to step S62A, and when it is determined to be a recording sheet, the process proceeds to step S64A. After step S62A or step S64A, the paper width is determined based on the signal pattern described above in step S7A. Then, the recording operation is started.

[0008]

In the control method of the above-mentioned ink jet recording apparatus, in the normal mode, it is possible to judge whether the recording medium has reached the sheet discharging means normally by the sheet discharging sensor. In this case, even if the recording medium is normally fed by a predetermined paper feed amount, the leading edge of the recording medium does not reach the paper ejection sensor, and whether the recording medium is normally fed by the paper ejection sensor. There is a problem that it is not possible to determine whether or not it is.

The present invention has been made in view of the above points,
The purpose is to be able to judge the feeding state of the recording medium without complicating the configuration even when the recording medium is fed to a predetermined position on the platen and then image recording is started. Another object of the present invention is to provide an image recording apparatus.

[0010]

That is, according to the present invention, the width of the recording medium is detected by the paper width detecting means after the recording medium is fed until it reaches a predetermined position on the platen, and the width is detected based on the detected width. In the image recording apparatus for controlling the image recording operation, the quality of the conveyance state of the recording medium is judged based on the signal obtained by the paper width detecting means.

According to the present invention, the width of the recording medium is detected by the paper width detecting means after the recording medium is fed until it reaches a predetermined position on the platen, and the image recording operation is performed according to the detected width. In the image recording apparatus to be controlled, the amount of positional deviation of the recording medium fed onto the platen is detected based on the signal obtained by the paper width detecting means.

Thus, the paper width detecting means for detecting the width of the recording medium is also used to detect whether the recording medium is conveyed or not, or whether the recording medium is misaligned.

[0013]

The two paper width sensors arranged side by side in the carrying direction of the recording medium are moved in the direction (paper width direction) orthogonal to the carrying direction, and two output patterns are obtained for the two output patterns obtained. Based on the judgment result of whether the output patterns are displaced and whether the two output patterns are at the predetermined positions, it is determined whether the front end of the paper reaches the predetermined position on the platen or not by the diagonal feed (jam). Whether or not there is a displacement in the paper width direction is detected.

[0014]

1 is a sectional view of a first embodiment of an ink jet recording apparatus of the present invention, FIG. 2 is a plan view of a platen portion of the same embodiment, and FIG. 3 is a perspective view of a carriage of the same embodiment. Is. The embodiment will be described with reference to these drawings.

As shown in FIG. 1, at the bottom of the main body 1, coated paper cut to a predetermined size (paper coated on the surface to facilitate ink absorption), clear sheet for OHP, etc. The cassette 2 accommodating the recording medium 3 is detachably installed. A pickup roller 4 is installed above one end of the recording medium 3,
Two guide plates 5a adjacent to the pickup roller 4,
5b is provided. On the left side of the two guide plates 5a, 5b in the figure, a pair of paper feed rollers 6a, 6 serving as paper feed means.
b, the platen 7, and a pair of paper discharge rollers 8a and 8b serving as paper discharge means are installed in sequence in order. The paper feeding means and the paper discharging means constitute a conveying means. A discharge tray 9 is detachably mounted on the left side of the pair of discharge rollers 8a and 8b in the figure so as to project to the outside of the main body 1. The paper feed sensor 10 is attached to the guide plate 5a.
Is disposed close to the paper feed roller 6a, while the paper discharge sensor 11 is installed at a position close to the right side of the paper discharge roller 8a in the figure (see FIG. 2). Each of the paper feed sensor 10 and the paper discharge sensor 11 is of a type that reads the reflected light from the recording medium 3 by a reflective photosensor provided facing the recording medium 3 or is in contact with the recording medium 3. This is a method of detecting the displacement of a lever that is movable by a photo sensor or a micro switch. Although not shown, in the immediate vicinity of the discharge roller 8a on the discharge tray 9 side,
In the case of manual recording described later, a movable lever of the paper discharge sensor 11 is arranged to detect the front end of the recording medium manually inserted from the paper discharge tray 9.

The carriage 12 is slidably fitted to a guide shaft 13 installed in the main body 1 in parallel with the paper feed roller 6a, and is driven by a driving means such as a timing belt, a pulley and a motor (not shown). The recording medium 3 is reciprocated in the paper width direction (the direction of arrow B and the opposite direction) perpendicular to the transport direction (direction of arrow A) which is the direction in which it is fed on the platen 7. A recording head 14 that ejects ink from an ejection port (not shown) to perform recording is detachably mounted on the carriage 12, and an ejection port surface 14a where the ejection port of the recording head 14 is opened is different from the platen 7. And face each other with a predetermined gap (for example, 0.75 mm). A paper width sensor 15 is installed on the carriage 12 in the immediate vicinity of the ejection port surface 14a, and the paper width sensor 15 is a reflection type photo sensor that emits light and reads the amount of reflected light. Paper width sensor 15 on platen 7
A silver plate 16 (see FIG. 2) whose surface is plated with nickel for increasing the amount of reflected light is attached to a part of the path of the irradiation light. The other surface of the platen 7 is
Black zinc plating is applied to reduce the amount of reflected light. Further, the paper width sensor 15 and the ejection port of the recording head 14 are separated from each other in the transport direction by the distance between the front end of the recording medium 3 and the front end of the recordable area 3b in the case of the front-rear end mode (see FIG. 5) described later. ing.

The operation when the recording medium 3 is conveyed will be described. The uppermost one of the recording media 3 is sent out between the two guide plates 5a and 5b by the pickup roller 4, and the tip thereof reaches the nip portion of the pair of paper feed rollers 6a and 6b. After that, the recording medium 3 is nipped and conveyed by the pair of paper feed rollers 6a and 6b rotating in the arrow direction (FIG. 1) in the drawing, and is conveyed along the platen 7 in the conveying direction (arrow A direction). .. The recording medium 3 that has passed through the platen 7 is nipped and conveyed by a pair of paper discharge rollers 8a and 8b that rotate in the direction of the arrow (FIG. 1) in synchronism with the pair of paper feed rollers 6a and 6b, and is discharged to a paper discharge tray 9 Is discharged to. The recording head 14 ejects ink onto the recording medium 3 on the platen 7 while moving by the carriage 12 to perform recording. In the case of manual recording, when the recording medium 3 is inserted along the paper discharge tray 9 and reaches the nip portion of the pair of paper discharge rollers 8a and 8b, it is not shown in the paper discharge sensor 11. Detected by the movable lever, the pair of paper discharge rollers 8a and 8b rotate in the direction opposite to the direction of the arrow (FIG. 1) in the drawing, and the recording medium 3 is moved in the direction opposite to the direction of the arrow A along the platen 7 to a predetermined position. Send only the paper feed amount.
At this time, the pair of paper feed rollers 6a and 6b also rotate in the direction opposite to the arrow direction (FIG. 1) shown in the figure in synchronization with the pair of paper discharge rollers 8a and 8b. After the recording medium 3 is sent to a predetermined position, the recording medium 3 is conveyed in the direction of arrow A and discharged to the paper discharge tray 9 in accordance with recording by the recording head 14.

Next, the operation of detecting the paper width and the paper type will be described. The carriage 12 moves from the position shown in FIG. 2 in the direction of arrow B to the opposite side of the platen 7. That is, the paper width sensor 15 moves in the direction of the arrow B so as to cross the area where the front end of the recording medium should be in the front / rear end mode.
During this movement, the paper width sensor 15 emits light toward the platen 7 and reads the amount of reflected light.

FIGS. 4A to 4D are diagrams showing the respective signal patterns obtained by the paper width sensor 15. The horizontal axis corresponds to the moving path of the irradiation light on the platen 7, and the vertical axis. The amount of reflected light is shown. When the recording medium 3 is located at the position shown by the solid line in FIG. 2, that is, when it does not reach the movement path of the irradiation light on the platen 7, the signal pattern obtained by the paper width sensor 15 is shown in FIG. It becomes like the signal pattern 1 shown. The small convex portion of the signal pattern 1 indicates the amount of reflected light from the silver plate 16 of the platen 7.
The recording medium 3 is at the position shown by the alternate long and short dash line in FIG.
When the front end of the recording medium 3 covers the silver plate 16 and reaches a predetermined position in the trailing edge mode, the recording medium 3
Is a coated paper (white), the signal pattern obtained by the paper width sensor 15 is like the signal pattern 2 shown in FIG. The convex portion of the signal pattern 2 indicates the amount of light reflected from the coated paper. The recording medium 3 is O
When the sheet is a clear sheet for HP (transparent), the signal pattern obtained by the paper width sensor 15 is like the signal pattern 3 shown in FIG. The wide convex portion of the signal pattern 3 indicates the amount of reflected light from the clear sheet, and the small convex portion indicates the amount of reflected light of the silver plate 16 that has passed through the clear sheet. When the signal pattern is not obtained as shown in FIG. 4D, it can be determined that the paper width sensor 15 and the platen 7 are abnormal.

FIG. 5A is a diagram showing a recordable area in the normal mode of the ink jet recording apparatus of this embodiment, and FIG. 5B is a diagram showing a recordable area in the front / rear edge mode. is there. Recordable area 3a in normal mode
The leading end in the transport direction (arrow A direction) of the (hatched area in the figure) is located 16 mm inside from the leading end of the recording medium 3, and the trailing end of the recordable region 3 a is the rear of the recording medium 3. The position is 18 mm inside from the edge. In the case of the front / rear end mode, the front and rear ends of the recordable area 3b are located 5 mm inside from the front and rear ends of the recording medium 3, respectively.
The normal mode and the front / rear end mode are selected by the normal mode key 17b and the front / rear end mode key 17c on the operation panel 17 provided on the main body 1 (see FIG. 6). The start key 17a is a start key for starting recording.

FIG. 7 is a block diagram of a control system of the ink jet recording apparatus of this embodiment. The control unit 18 includes a CPU 18a that executes a process of a first embodiment of a method for controlling an inkjet recording apparatus according to the present invention described below, and a ROM 18b that stores fixed data such as a program corresponding to the process.
And a working RAM 18c.

FIG. 8 is a flow chart of the first embodiment of the control method of the ink jet recording apparatus of the present invention, and this embodiment will be described with reference to this drawing.

To carry out this embodiment, the first embodiment of the ink jet recording apparatus described above is used. When there is a recording start command, first, in step S1, the recording medium 3 is sent out from the cassette 2 by the pickup roller 4. In step S2, the presence / absence of the recording medium 3 is determined by the paper feed sensor 10. If it is determined that there is no recording medium 3, the process proceeds to step S3 to notify that the recording medium 3 is not in the cassette 2, and if it is determined to be present, the process proceeds to step S4. In step S4, it is determined whether or not the front / rear end mode is selected. If the front / rear end mode is selected, the process proceeds to step S5, in which the front end of the recording medium 3 has passed the ejection port surface 14a of the recording head 14 and has a predetermined position. The recording medium 3 is paired with a pair of paper feed rollers 6a, 6 by the paper feed amount C required to reach the position (the position shown by the one-dot chain line in FIG. 2).
Send by b, and proceed to step S9. In the case of the normal mode, the process proceeds to step S6, and the recording medium 3 is fed as a pair by the paper feed amount D required for the front end of the recording medium 3 to be nipped by the pair of discharge rollers 8a and 8b. Rollers 6a, 6b
Send by. Then, in step S7, the paper ejection sensor 11
The presence / absence of the recording medium 3 is determined by, and if it is determined that the recording medium 3 is not present, the process proceeds to step S8 to notify that the leading edge of the recording medium 3 has not reached the pair of paper discharge rollers 8a and 8b and is a jam. If it is determined that the recording medium 3 is present, the process proceeds to step S9. In step S9, the carriage 12 is moved in the paper width direction (direction of arrow B) to detect the paper width and paper type, and the paper type is determined based on the signal pattern obtained by the paper width sensor 15 in step S10. When the signal pattern is the signal pattern 1 shown in FIG. 4A, it is determined that the recording medium 3 has not reached the predetermined position on the platen 7, and the process proceeds to step S101 to notify the jam. .. If the signal pattern is the signal pattern 2 shown in FIG. 4B, it is determined that the recording medium 3 is coated paper, and the process proceeds to step S102. When the signal pattern is the signal pattern 3 shown in FIG. 4C,
It is determined that the recording medium 3 is a clear sheet for OHP, and the process proceeds to step S103. In the case of the signal pattern 4 shown in FIG. 4D, the paper width sensor 15, the platen 7,
When it is determined that an abnormality has occurred in the carriage 12 or the like, the process proceeds to step S104 and the abnormality is notified. Step S1
02 or after step S103, step S1
In step 1, the paper width is determined based on the signal pattern 2 or the signal pattern 3 described above. Then, the recording operation is started.

In the case of recording by manual feeding and in the front / rear end mode, the following is performed. Approximately 1 second after the recording medium 3 inserted from the paper discharge tray 9 is detected by the movable lever (not shown) of the paper discharge sensor 11, the recording medium 3 is fed by the conveying means in the direction opposite to the arrow A direction. Paper feed sensor 1
Even if 0 detects that there is paper, the recording medium 3 continues to be fed, and when the paper discharge sensor 11 detects that there is no paper, it is necessary for the front end of the recording medium 3 to move from that position to a predetermined position in the front-end mode. The recording medium 3 is fed in the direction opposite to the arrow A direction by the appropriate paper feed amount. After that, it is the same as step S9 and subsequent steps shown in FIG.

In the control method of the ink jet recording apparatus of the present embodiment, the signal pattern 1 obtained by the paper width sensor 15 is also used to judge whether or not the front end of the recording medium 3 is at a predetermined position on the platen 7. Therefore, the jam can be detected even in the front / rear end mode in which the paper discharge sensor 11 cannot be used. As a result, the ink can be prevented from hitting the platen, and the surface of the apparatus and the recording medium 3 on the platen 7 side can be kept clean.

FIG. 9 is a perspective view of the carriage of the second embodiment of the ink jet recording apparatus of the present invention, and FIG. 10 is a plan view of the platen portion of the same embodiment. The embodiment will be described with reference to this figure.

Two paper width sensors are installed on the carriage 32 in the vicinity of the ejection opening surface (not shown) of the recording head 14 side by side in the carrying direction (direction of arrow A), and the upstream side in the carrying direction is the first paper width. The sensor 35a and the second paper width sensor 35b on the downstream side. The first paper width sensor 35a and the second paper width sensor 35b are provided with an appropriate gap (for example, 5 mm) along the transport direction, and the first paper width sensor 35a is also provided.
And the ejection port (not shown) of the recording head 14 are separated from each other in the transport direction by the distance between the front end of the recording medium and the front end of the recordable area in the front / rear mode. Platen 27
Includes the first paper width sensor 35a and the second paper width sensor 35
A first silver plate 36a and a second silver plate 36b are provided at positions corresponding to b, respectively. Except for the points described above, the structure is the same as that of the first embodiment of the ink jet recording apparatus.

In the paper width and paper type detecting operation of this embodiment, the carriage 32 is moved from the position shown in FIG. 10 in the paper width direction (arrow B direction) perpendicular to the carrying direction (arrow A direction). The first paper width sensor 35a moves in the paper width direction so as to cross the area (the area indicated by the alternate long and short dash line in FIG. 10) where the leading edge of the recording medium should be in the front / rear edge mode, and the second paper width sensor 35b The sheet moves in the paper width direction on the downstream side of the transport direction.

Next, a second embodiment of the control method of the ink jet recording apparatus of the present invention will be described. The second embodiment of the ink jet recording apparatus described above is used for carrying out this embodiment.

In the step of determining the paper type when the front / rear edge mode is selected, the first paper width sensor 35a and the second paper width sensor 35a
If both of the signal patterns obtained by the paper width sensor 35b are the signal pattern 1 shown in FIG. 4A, it is determined that the leading end of the recording medium 3 has not reached a predetermined position, and it is a jam. Let me know. The signal pattern of the first paper width sensor 35a is the signal pattern 2 in FIG. 4 (b), and the signal pattern of the second paper width sensor 35b is in FIG. 4 (a).
If the signal pattern 1 is No. 1, the leading end of the recording medium 3 has reached a predetermined position, it is determined that the recording medium 3 is coated paper, and the process proceeds to the subsequent paper width determination step. The signal pattern of the first paper width sensor 35a is shown in FIG.
Signal pattern 3 and the second paper width sensor 35b
4A is the signal pattern 1 in FIG. 4A, the leading end of the recording medium 3 has reached a predetermined position, and it is determined that the recording medium 3 is a clear sheet for OHP. , And then proceed to the paper width determination step. When both the signal patterns of the first paper width sensor 35a and the second paper width sensor 35b are the signal pattern 2 shown in FIG. 4B or the signal pattern 3 of FIG. When it is determined that the front end of the medium 3 has exceeded the predetermined position, the recording medium 3 is moved in the direction opposite to the arrow A direction by the conveying means until the front end of the recording medium 3 returns to the predetermined position. The signal pattern of at least one of the first paper width sensor 35a and the second paper width sensor 35b is shown in FIG.
In the case of the signal pattern 4 of (d), it is determined that an abnormality has occurred and the abnormality is notified.

Except for the points described above, the present embodiment is the same as the first embodiment of the control method for the ink jet recording apparatus.

In this embodiment, in addition to the effect of the first embodiment of the method for controlling the ink jet recording apparatus, the tip of the recording medium 3 has not reached a predetermined position on the platen 7,
The front end of the recording medium 3 has reached a predetermined position on the platen 7, and the front end of the recording medium 3 is the platen 7.
There is an effect that it is possible to separately detect that the predetermined position above is exceeded.

Next, a third embodiment of the present invention will be described. In the first and second embodiments described above, in the front / rear edge mode, it is checked based on the output of the paper width sensor whether or not the front end of the recording medium has reached a predetermined position on the platen. Based on the output, the positional deviation of the recording medium in the lateral direction (direction perpendicular to the transport direction) is checked. FIG. 11 is a flowchart showing the control procedure of this embodiment. After the paper width is determined in step S11, the position of the recording medium is determined in step S12. The processing in the other steps is the same as that in FIG.

FIG. 12 shows the procedure of this recording medium position determination processing. It is checked from the output data of the paper width sensor 15 whether the recording medium is displaced to the left or right.

In this embodiment, it is checked whether the left end position of the signal pattern, which is the detection output of the sensor, is at the standard position, or if it is off, how much it is off. First, in step S121, the output pattern of the paper width sensor 15 is checked. If the pattern is as shown in FIG. 13A, it is determined that the recording medium is correctly fed and the recording operation is started.
With the patterns shown in FIGS. 13B and 13C,
It is considered that each recording medium is laterally displaced from the lateral direction. In step S122, the amount of deviation is checked and 3.5
If it is not less than mm, it is judged as a jam in step 123. 3.5
If it is less than mm, the recording position of the deviation amount is corrected in step S124. The threshold value of 3.5 mm, which is the threshold value for determining the amount of deviation, is 5 for the left and right margin amounts of the recording medium of this embodiment.
It is decided from mm. Step S124
The recording position correction of is to change the setting of the recording operation parameter so as to change the recording position (X direction in the drawing).
FIG. 14 shows the displacement of the recording image position when the recording medium is laterally displaced and conveyed. Figure 14 (b)
If the recording medium shifts to the left or right as in (c) or (c), the image area also shifts to the left or right. Parameters such as recording timing are reset so that an image can be correctly recorded in the center of the recording medium as shown in (a). In the case of FIG. 14, both (b) and (c) are offset by 3 mm to the left and right, so correction of 3 mm is performed.

Next, a fourth embodiment of the present invention will be described. In the second embodiment, two paper width sensors are provided to detect that the front end of the recording medium has reached the predetermined position of the platen and has exceeded the predetermined position. In addition, the skew of the recording medium is detected and the operation of the apparatus is controlled.

FIG. 15 is a plan view of the platen portion of the ink jet recording apparatus in this embodiment. In the figure, FIG.
Those having the same numbers as are the same components. First
An appropriate gap (for example, about 10 mm) is provided between the paper width sensor 35a and the second paper width sensor 35b along the transport direction. In the paper width / paper type detection operation, the carriage 32 is moved from the position shown in FIG. 15 in the paper width direction (arrow B direction) perpendicular to the transport direction (arrow A direction). This is the second
It is similar to the embodiment. The first paper width sensor 35a moves in the paper width direction so as to cross the leading end portion of the recording medium in the front / rear end mode, and the second paper width sensor 35b moves in the paper width direction on the downstream side in the transport direction of the area. .. The feature of this embodiment is that the two paper width sensors 35a and 35b are used to further finely examine the position of the recording medium and control is performed according to each case. Since the entire control procedure in this embodiment is the same as that in FIG. 11, its description is omitted.

FIG. 16 is a flow chart for determining the position of the recording medium. In step S121, the pattern of the first paper width sensor 35a is checked. Next, steps S122 to S12
At 4, the pattern of the second paper width sensor 35b is checked.
In step S121, if the pattern of the first paper width sensor 35a is shown in FIG.
If so, the process proceeds to step S123, and if FIG. 13 (c), the process proceeds to step S124. (A) judges that the paper is in the correct position at the point where the first paper width sensor 35a has passed, (b)
And (c) are shifted to the left and right respectively. Then, in step S122, the output pattern of the second paper width sensor 35b is checked. In the case of FIG. 13A, the recording position is not corrected in step S125 and the recording operation is performed. First and second
That the paper width sensor of FIG.
This is because the recording medium is conveyed to the correct position as shown in (a). If the output patterns of the first and second paper width sensors are shown in FIGS. 13B and 13C, step S1
The process proceeds to step 30 of the jam clearance routine. Because the output pattern of the first paper width sensor 35a is (a),
This is because it is considered that the sheets are fed obliquely as shown in FIGS. 18 (a) and 18 (b). A case similar to this can be said in steps S123 and S124.
That is, the output pattern data of the first paper width sensor 35a is shown in FIG.
In the case of 3 (b), if the output pattern data of the second paper width sensor 35b is as shown in FIG. 13 (a) or 13 (c), a jam will occur in step S130. Also, the first paper width sensor 3
If the output pattern data of 5a is as shown in FIG.
The output pattern data of the paper width sensor 35b is shown in FIG.
Alternatively, in the case of (b), a jam occurs in step S130.

Further, both the output patterns of the first paper width sensor 35a and the second paper width sensor 35b are as shown in FIG. 13 (b), that is, the fed recording medium is as shown in FIG. 18 (a). However, in this case, in step S126, the deviation amounts of the output patterns from the first and second paper width sensors 35a and 35b are each 3.5 mm or less, and the difference between the two is 0.
If so (state as shown in FIG. 17B), the recording position is corrected in step S127, and the process proceeds to the recording operation.

Similarly, when the output patterns of the first paper width sensor 35a and the second paper width sensor 35b are both as shown in FIG. 13C, that is, when the fed recording medium is as shown in FIG. 18B. Check in step S128. If the deviation amount is 3.5 mm or less and the difference between the two is 0 (see FIG. 17).
(State (c)) The recording position is corrected in step S129, and the process proceeds to the recording operation.

By using the signal pattern obtained by the paper width sensor in this way to judge the feeding state of the recording medium, it is possible to prevent the ink from hitting the platen, and the platen side of the apparatus or the recording medium is prevented. The surface of can be kept clean.

When the recording medium is fed while being shifted in the X direction as shown in FIGS. 18B and 18C, the left and right margins can be adjusted by shifting the recording start position. Therefore, good image recording can be realized.

Next, an example of the recording head used in each of the above-described embodiments will be described.

In FIG. 19, the recording head unit 61
In order to eject ink from a plurality of ejection ports 62 arranged in a row, an electrothermal converter 63 that is supplied with an applied voltage to generate thermal energy is provided for each ink flow path. There is. Then, by applying a drive signal, thermal energy is generated in the electrothermal converter 63 to cause film boiling, and bubbles are formed in the ink flow path. Then, the ink is ejected from each of the ejection ports 62 by the growth of the bubbles.

The present invention has excellent effects particularly in a recording head and a recording apparatus of the type which ejects ink by utilizing thermal energy among the ink jet recording systems.

Regarding the typical structure and principle thereof, see, for example, US Pat. Nos. 4,723,129 and 4740.
What is done using the basic principles disclosed in 796 is preferred. This method can be applied to both the so-called on-demand type and continuous type, but especially in the case of the on-demand type, a liquid (ink) is used.
By applying at least one drive signal to the electrothermal converter arranged corresponding to the sheet or liquid path holding the , Heat energy is generated in the electrothermal converter, and the film is boiled on the heat acting surface of the recording head,
As a result, bubbles can be formed in the liquid (ink) in a one-to-one correspondence with this drive signal, which is effective. The growth of this bubble,
The contraction causes the liquid (ink) to be ejected through the ejection opening to form at least one droplet. It is more preferable to make this drive signal into a pulse shape, because the bubble growth and contraction are immediately and appropriately performed, so that the ejection of the liquid (ink) with excellent responsiveness can be achieved. As the pulse-shaped drive signal, U.S. Pat. Nos. 4,463,359 and 43,
Those as described in 45262 are suitable. If the conditions described in US Pat. No. 4,313,124 of the invention relating to the rate of temperature rise on the heat acting surface are adopted, more excellent recording can be performed.

As the constitution of the recording head, in addition to the combination constitution of the ejection port, the liquid passage, and the electrothermal converter (the linear liquid passage or the right-angled liquid passage) as disclosed in the above-mentioned respective specifications. U.S. Pat. No. 4,558,333, US Pat. No. 4,558,333, which discloses a configuration in which a heat-acting surface is arranged in a bending region.
The present invention is also effective for a structure using the specification of No. 459600. In addition, Japanese Laid-Open Patent Publication No. 123670/1984 discloses a configuration in which a common slit is used as a discharge portion of a plurality of electrothermal converters, and an opening for absorbing a pressure wave of thermal energy. The present invention is also effective as a configuration based on Japanese Patent Application Laid-Open No. 138461/1984, which discloses a configuration in which the above is associated with the discharge portion.

Further, as a full line type recording head having a length corresponding to the width of the maximum recording medium which can be recorded by the recording device, a combination of a plurality of recording heads as disclosed in the above-mentioned specification can be used. It may have either a structure satisfying the length or a structure as one recording head integrally formed, but the present invention can more effectively exhibit the above-mentioned effects.

In addition, by being mounted on the apparatus main body, a replaceable chip type recording head that enables electrical connection to the recording apparatus main body and supply of ink from the recording apparatus main body, or the recording head itself The present invention is also effective when a cartridge-type recording head integrally provided in the recording medium is used.

Further, it is preferable to add recovery means for the recording head, preliminary auxiliary means, etc., which are provided as a configuration of the recording apparatus of the present invention, because the effects of the present invention can be further stabilized. Specifically, these are capping means, cleaning means, pressurizing or suctioning means, electrothermal converters or heating elements other than these, or preheating means for the recording head. ,
It is also effective to perform stable recording by performing a preliminary discharge mode in which discharge different from recording is performed.

Further, the recording mode of the recording apparatus is not limited to the mode in which only the mainstream color such as black is recorded, but the recording head may be integrally formed or a plurality of combinations may be used. Alternatively, the present invention is extremely effective for an apparatus provided with at least one of full colors by color mixing.

In this embodiment described above, the ink is described as a liquid, but it is an ink that solidifies at room temperature or below, and is softened or liquid at room temperature, or the ink itself is 30 in the above ink jet. Generally, the temperature is controlled in the range of ℃ or more and 70 ° C. or less to control the temperature of the ink so that the viscosity of the ink is in the stable ejection range. good. In addition, it is possible to prevent the temperature rise due to thermal energy from being positively used as energy for changing the state of the ink from a solid state to a liquid state, or to use an ink that solidifies when left standing for the purpose of preventing ink evaporation. However, in any case, by applying heat energy such as ink that is liquefied by being applied according to a recording signal of heat energy and ejected as an ink liquid or that has already started to solidify when it reaches the recording medium. The use of an ink having a property of liquefying for the first time is also applicable to the present invention. In such a case, the ink is retained as a liquid or solid in the recesses or through holes of the porous sheet as described in JP-A-54-56847 or JP-A-60-71260, It may be configured to face the electrothermal converter. In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

[0053]

Since the present invention is configured as described above, it has the following effects.

The recording medium is also used for judging whether the recording medium is in the good or bad state on the basis of the signal obtained by the paper width detecting means, so that the recording medium can be moved to a predetermined position on the platen without a special sensor. It is possible to detect that it has not reached and the positional deviation. As a result, it is possible to prevent the platen from hitting, and it is possible to keep the surfaces of the apparatus and the recording medium on the platen side clean.

[Brief description of drawings]

FIG. 1 is a sectional view of a first embodiment of an inkjet recording apparatus of the present invention.

FIG. 2 is a plan view of a platen portion of the embodiment.

FIG. 3 is a perspective view of the carriage according to the embodiment.

FIG. 4 is a diagram showing respective signal patterns obtained by the paper width sensor of the embodiment.

5A and 5B are diagrams showing recordable areas in the normal mode and the front / rear end mode of the embodiment, where FIG. 5A shows the normal mode and FIG. 5B shows the front / rear end mode.

FIG. 6 is a diagram showing an operation panel of the embodiment.

FIG. 7 is a block diagram of a control system of the embodiment.

FIG. 8 is a flowchart of a first embodiment of a method for controlling an inkjet recording apparatus of the present invention.

FIG. 9 is a perspective view of the carriage of the second embodiment of the inkjet recording apparatus of the present invention.

FIG. 10 is a plan view of a platen portion of the embodiment.

FIG. 11 is a flowchart of a third embodiment of a method for controlling an inkjet recording apparatus of the present invention.

FIG. 12 is a flowchart showing the flow of a position determination process for a recording medium according to the third embodiment of the present invention.

FIG. 13 is a diagram showing an output pattern of a paper width sensor.

FIG. 14 is a diagram showing a relationship between a feeding state of a recording medium and an image area.

FIG. 15 is a plan view showing a platen portion of a fourth embodiment of the ink jet recording apparatus of the present invention.

FIG. 16 is a flowchart showing the flow of a position determination process for a recording medium according to the fourth embodiment of the present invention.

FIG. 17 is a diagram showing a state of a recording medium fed on a platen.

FIG. 18 is a diagram illustrating a state of a recording medium that is fed obliquely.

FIG. 19 is a perspective view of a main part of a recording head used in each embodiment of the present invention.

FIG. 20 is a flowchart of a conventional method for controlling an inkjet recording apparatus.

[Explanation of symbols]

 1 main body 2 cassette 3 recording medium 4 pickup roller 5a, 5b guide plate 6a, 6b paper feeding roller 7,27 platen 8a, 8b paper ejection roller 9 paper ejection tray 10 paper feed sensor 11 paper ejection sensor 12, 32 carriage 13 guide Axis 14 Recording head 14a Discharge port surface 15 Paper width sensor 16 Silver plate 17 Operation panel 18 Control unit 35a First paper width sensor 35b Second paper width sensor 36a First silver plate 36b Second silver plate

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical display location B41J 13/00 9210-2C 29/42 B 8804-2C 29/48 A 8804-2C

Claims (14)

[Claims] 1. A recording medium is fed until it reaches a predetermined position on a platen, and then the width of the recording medium is detected by a paper width detecting means, and an image recording operation is controlled based on the detected width. In the image recording apparatus, the quality of the conveyance state of the recording medium is judged based on a signal obtained by the paper width detecting means. 2. The image recording apparatus according to claim 1, wherein the paper width detection unit detects the presence or absence of the recording medium in a recordable area of a recording head. 3. The presence / absence of the recording medium is detected based on a signal obtained by moving the paper width detecting means in a direction perpendicular to the conveying direction of the recording medium. Or the image recording device described in 2. 4. The paper width detecting means has first and second paper width sensors for detecting the presence or absence of the recording medium at different positions with respect to the conveyance direction of the recording medium, and the first paper width. The image recording apparatus according to claim 1, wherein the conveyance state of the recording medium is determined based on an output signal of a sensor and an output signal of the second paper width sensor. 5. The image recording apparatus according to claim 1, wherein an image is recorded by ejecting ink droplets onto a recording medium fed onto the platen. 6. The image recording apparatus according to claim 5, wherein the ink droplets are ejected by causing a state change in the ink by using thermal energy. 7. An image recording apparatus for detecting the width of the recording medium by the paper width detecting means after feeding the recording medium to a predetermined position on the platen, based on a signal obtained by the paper width detecting means. An image recording apparatus, which detects a positional deviation amount of a recording medium fed onto the platen. 8. The recording position on the recording medium is controlled based on the positional deviation amount so as to record an image at an appropriate position on the recording medium when the positional deviation amount is equal to or less than a predetermined amount. The image recording apparatus according to claim 7. 9. When the positional deviation amount exceeds a predetermined amount,
The image recording apparatus according to claim 7, wherein a recording operation on the recording medium is prohibited. 10. The paper width detecting means has first and second paper width sensors for detecting the presence or absence of the recording medium at different positions in the conveying direction of the recording medium, and the first paper width. 6. A recording operation is controlled by determining a conveyance state of the recording medium according to a positional deviation amount based on an output signal of the sensor and a positional deviation amount based on an output signal of the second paper width sensor. 7. The image recording device according to item 7. 11. A recording operation on the recording medium is prohibited when the positional deviation amount based on the output signal of the first paper width sensor and the positional deviation amount based on the output signal of the second paper width sensor are different. The image recording apparatus according to claim 10, wherein: 12. When an amount of positional deviation based on an output signal of the first paper width sensor and an amount of positional deviation based on an output signal of the second paper width sensor are the same, an image is formed at an appropriate position on the recording medium. Based on the amount of positional deviation to be recorded,
The image recording apparatus according to claim 10, wherein a recording position on the recording medium is controlled. 13. The image recording apparatus according to claim 7, wherein an image is recorded by ejecting ink droplets onto a recording medium fed onto the platen. 14. The image recording apparatus according to claim 13, wherein the ink droplets are ejected by causing a state change in the ink by using thermal energy.