JP2001315320A - Ink jet printer equipped with cleaning unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an ink jet printer in which a platen for guiding a sheet at a recording section is prevented from being stained with unnecessary ink to cause staining on the rear surface of a next sheet. SOLUTION: A platen 9 disposed oppositely to an ink head 10 at a recording section is provided with a cleaning unit 20 including a cleaning member 21 on the side opposite to the ink head 10. The platen 9 is movable between a recording position spaced apart from the ink head 10 by a specified interval and a cleaning position abutting against the cleaning member 21. When a sheet passes through the recording section, the platen 9 is moved to a cleaning position and turned at least one revolution while touching the cleaning member 21 thus removing unnecessary ink I.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning apparatus for an ink jet printer, which prevents a back surface of a recording medium opposite to a recording surface from being stained.

[0002]

2. Description of the Related Art A recording apparatus (printer) forms a visible image on a sheet as a recording medium so that image data obtained by reading an image of a document, image data input from another apparatus, and the like can be viewed. This is output as a hard copy. This recording device is, for example, an electrophotographic system,
In general, an ink jet system in which ink is selectively discharged to perform recording, a thermal recording system having a thermal head having thermal paper or thermal transfer ink, or the like is used.

In this case, in particular, an image forming apparatus using an ink jet system, that is, an ink jet printer selectively discharges ink in accordance with input image data, and applies a color ink to a sheet as a recording medium to be conveyed. Thus, a visible image is formed by dots. The recorded / reproduced image, that is, the image based on the ink dots, reaches the entire sheet when a sheet is fed in the width direction of the input image data. Therefore, there is no particular problem when the size of the image data input to the printer matches the sheet size to be fed or when the sheet size is larger.

That is, as shown in FIG. 12A, when the width W1 of image data to be recorded is larger than the width W2 of a sheet P as a recording medium, the width of the sheet P other than the sheet P, for example, at both ends. Ink dots are ejected to a portion where a corresponding sheet does not exist, and the ink dots adhere as unnecessary ink I to a platen 100 that supports the sheet rear surface and guides the sheet. FIG. 12B shows that the length L2 of the sheet P in the feed direction is equal to the length L of the image data to be recorded.
If it is shorter than 1, recording dots of the remaining image data are ejected from the rear end of the sheet P to the platen 100 side and adhere as unnecessary ink I.

Therefore, the sheet P, which is a recording medium described above,
The ink dots that are not recorded (formed on the sheet P) adhere to the surface of the platen 100 and stain the platen 100 with the ink I. This unnecessary ink I is liquid and undried, so that the next sheet P is sent,
The back surface of the sheet is stained with unnecessary ink. This generally results in offset recording and is unsightly.

In order to solve such a problem, for example, Japanese Unexamined Utility Model Publication No. 4-122037 discloses a case where unnecessary ink is attached to the platen as described above after recording (printing) by ink jet. In order to clean the ink, a cleaning device provided with a cleaning member is provided on an ink head that is reciprocally scanned for recording so as to clean the platen surface.

That is, after printing is completed, the cleaning member is pressed against the platen, and in this state, the ink head is reciprocated. By performing this for the entire circumference of the platen, the cleaning is completed, and the next print (printing) is performed.

[0008]

As described above, after recording on one sheet, if ink adheres to a platen on an unnecessary portion, the back surface of the next sheet is stained with the unnecessary ink. In order to prevent the offset from occurring, the cleaning member is pressed against the platen, and in this state, the ink head is driven to reciprocate to clean excess ink adhering to the platen surface.

According to such a configuration, the cleaning member is mounted on the ink head, and the cleaning member is movably provided at a retracted position separated from the platen and a cleaning position pressed against the platen. Therefore, the driving load when the ink head is reciprocated greatly differs between recording and cleaning. Therefore, in order to perform the cleaning operation, it is necessary to use a driving motor having a large driving force capable of pressing the cleaning member against the platen and reciprocating the ink head. In this case, the cost increases as a whole.

In addition, when the cleaning member is pressed against the platen and the cleaning operation is repeatedly performed, the positional relationship between the ink head and the platen is deviated, and a recording deviation (distortion) or the like occurs, and the recorded image quality is deteriorated. I am concerned. That is, the platen and the ink head are positioned so as to keep a constant interval. Normally, during recording, the ink head and the platen do not come into contact with each other, and there is no factor that breaks the relationship at a fixed interval. However, when the cleaning member is pressed against the platen and the ink head is reciprocated in this state, it is expected that the positional relationship between the ink head and the platen will be greatly changed after the pressing of the cleaning member is released. In particular, deformation and fluctuation of the platen shaft are predicted.

Further, it is necessary to mount the cleaning member on a carriage for reciprocating with the ink head, which increases the weight of the entire carriage. Further, a movement and a drive mechanism for moving the cleaning member to a position for separating the cleaning member from the platen are required, so that the weight becomes large as a whole, which hinders high-speed driving of the ink head. In addition, the high-speed drive necessitates a longer approach distance for stable running. Therefore, the entire inkjet printer tends to be large in the scanning direction of the ink head, and tends to be large.

The present invention has been made in view of the above-mentioned problems,
An ink jet printer which aims to solve the problem and avoids the increase in the size of the apparatus, can efficiently clean a platen and the like contaminated with ink, and eliminates the burden of traveling drive on the ink head. The purpose is to provide.

In particular, an object of the present invention is to provide a cleaning apparatus for efficiently cleaning a platen contaminated with ink.

[0014]

According to the present invention, there is provided an ink jet printer having a cleaning device according to the present invention, wherein a platen for guiding a recording medium to a recording section facing an ink head for discharging ink is provided. Is provided, on the opposite side to the side facing the ink head with respect to the platen, a cleaning device that is positioned in a state separated from the platen, and includes a cleaning member for cleaning the platen surface, The platen may be movably provided between a recording position facing the ink head at a predetermined interval and a cleaning position in contact with the cleaning member.

According to this configuration, the platen can be cleaned without providing a cleaning member or the like to the ink head. Therefore, there is no adverse effect due to the weight due to the recording scan of the ink head, and it is possible to prevent the entire printer from being enlarged due to an increase in the scanning distance by the high-speed scanning. Also,
Since the cleaning is performed by moving the platen to the cleaning position, the positional relationship between the ink head and the platen does not significantly collapse, and there is no need to prepare a particularly large driving means, for example, a driving motor.
Factors that increase costs can be eliminated.

Therefore, in the ink jet printer having the above-described structure, a rear end detection sensor for detecting that the recording medium passes through the recording section facing the ink head is provided, and the rear end detection sensor detects the rear end of the recording medium. If the platen is moved to the cleaning position when the edge is detected, the interval (time) for performing the next printing without hindering the printing during the printing operation.
By using the cleaning member, unnecessary ink attached to the platen can be cleaned by the cleaning member.

Further, in the ink jet printer having the above-described configuration, a detection sensor for detecting a leading end of the recording medium is provided before a recording medium is guided to a recording section facing the ink head, and the leading end detection sensor The platen is returned to the recording position just before the recording medium is sent to the recording unit by moving the platen to the recording position at a fixed distance from the ink head by detecting the leading end of the recording medium. Further, it is possible to prevent the leading end of the recording medium from being caught, and to smoothly guide the recording medium through a narrow space between the ink head and the platen.

Further, in the ink jet printer having the above-described configuration, if a driving means for driving the platen is provided on the platen side, it is natural that the platen can be arbitrarily set during recording and cleaning. Can be driven.

As described above, on the platen side,
In a configuration in which a driving unit for driving the platen is provided, in a state where the platen is positioned at a recording position, a conveying unit for conveying a recording medium to a recording unit includes:
If the drive unit is connected to the drive unit and is positioned at the cleaning position so that the connection to the transport unit is released, the drive unit drives the platen, the drive during cleaning, and the recording. The drive for feeding the medium to the recording unit can be performed. In addition, since the driving of the transporting unit or the like is released during cleaning, a driving load is not applied to the driving unit during cleaning, and thus it is not necessary to provide a large driving unit.

On the other hand, when the above-mentioned driving means is provided on the platen side, the driving means rotates the platen at least one turn or more while the platen is positioned at the cleaning position, so that the entire surface around the platen is rotated. Can be cleaned, thereby preventing the back surface of the recording medium from being stained with unnecessary ink.

Further, in the apparatus in which the above-mentioned driving means is provided on the platen side, in order to feed the next recording medium to the recording section after the platen has been rotated at least one or more times in a state positioned at the cleaning position. If the configuration is such that the recording position is moved to the recording position and the recording position is in the standby state, the recording operation can be reliably performed without disturbing the feeding of the recording medium to the recording section by one driving unit. In addition, the cleaning process can be performed using the interval between the transports of the recording medium.

As described above, according to the configuration of the ink jet printer of the present invention, since the ink head side is not hindered at all, it is possible to prevent the entire printer from becoming large in the scanning direction, Does not need to be increased, and an increase in cost can be prevented, so that the above-described object can be achieved.

[0023]

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a configuration diagram showing details of a recording portion of an ink jet printer for describing an embodiment of the present invention. FIG. 2 is a perspective view of a recording portion shown in FIG. 1, and FIG. 3 is a configuration diagram showing a schematic configuration of the entire inkjet printer including the recording portion shown in FIG.

FIG. 4 is a perspective view showing an appearance provided with the mechanism shown in FIG. The configuration of the ink jet printer will be described with reference to FIGS.

First, in FIG. 4, reference numeral 1 denotes an ink jet printer main body, and reference numeral 2 denotes an upper cover including an operation panel disposed on the upper portion of the ink jet printer. The upper cover 2 including the operation panel is provided so as to be rotatable around a fulcrum shaft (not shown), and particularly, a recording unit of the ink jet printer can be opened. This facilitates operations such as cartridge replacement.

A detachable paper feed cassette 3 is provided below the printer 1. The paper feed cassette 3 stores therein a sheet, which is a recording medium of a predetermined size, and is mounted on a mounting portion of the main body of the printer 1 so that one of the stored sheets is fed from the top. It has become so.

The sheet fed from the paper feed cassette 3 is sent to a printing position via a sheet transport system, and is printed by an ink head which discharges ink located at the printing position. A record is made.
After the recording, the sheet is discharged to a discharge tray 4 disposed above the sheet cassette 3. The discharge tray 4 is provided detachably from the main body of the printer 1 and is mounted so as to protrude from the main body of the printer 1.

Next, the schematic structure of the inside of the ink jet printer 1 will be described with reference to FIG. In FIG. 3, a sheet P, which is a recording medium, is accommodated in the paper feed tray 3 which is detachable from the main body of the inkjet printer 1 as described above. In addition, a manual paper feed tray 3a for mounting and feeding arbitrary sheets is provided on the upper portion of the paper feed cassette 3.

The uppermost sheet P or the pick-up roller 5 for feeding the loaded sheet is placed above the loaded paper feed cassette 3 and above the manual feed tray 3a. 5a is arranged opposite to the upper end of the sheet. The pickup rollers 5, 5a
Is a sheet feeding means, and feeds out the sheet P by one rotation. The fed sheet P is supplied to a sheet feeding roller 6 provided corresponding to the pickup roller 5 and the like.
Is sent to

The paper feed roller 6 has a reverse path (U-shaped path).
The pickup roller 5
The sheet is nipped with the lower first pressure roller 7 arranged corresponding to the sheet conveying direction of the sheet fed out, and the sheet is reversely conveyed. Above the paper feed roller 6, a second pressure roller 8 is provided to further convey the sheet to be reversely conveyed to a target position, especially a recording position. The sheet feeding roller 6 and the first and second pressing rollers 7 and 8 constitute a sheet conveying means.

The sheet fed by the second pressure roller 8 and the paper feed roller 6 constitutes a registration means disposed before the recording position. That is, the registration unit temporarily stops the sheet P, and controls the conveyance and the start of the sheet P in synchronization with the recording start operation at the recording position. In addition, according to the inkjet printer 1, by terminating the recording operation for one line or a plurality of lines, sheet feeding of an amount corresponding to the line is started. When printing by ink ejection is being performed, the conveyance of the sheet P is stopped.

The second pressing roller 8 as the registration means
The sheet fed by the feeding roller 6 is guided to a recording position. In order to guide and convey the platen, a platen 9 having a belt structure is provided in the present invention. This platen 9
An ink head 10 for appropriately discharging ink droplets (dot ink) toward the sheet P guided and conveyed on the surface of the platen 9 is provided at a recording position opposite to.

The ink head 10 includes the ink carriage 1
1, the ink carriage 11 is slidably provided on a slide shaft (not shown) which is flatly provided, for example, in a direction orthogonal to the sheet conveying direction. As a result, the ink head 10 moves the sheet P conveyed by the start of recording in the direction orthogonal to the conveyance direction by one.
By scanning, dot recording of a required number of lines is performed.

At this time, when the ink head 10 scans,
As described above, the sheet P is stopped, the ink ejection control is performed in accordance with the image data, and the sheet feeding control is performed on the sheet P in accordance with the amount of the recording line when the recording of the line is completed. During this sheet feeding, the ink head 10 is driven to return to the home position where the original scanning starts. By repeating this sequentially, it is possible to reproduce and record an image for one page using ink dots corresponding to the image data.

The sheet P on which the recording has been completed is discharged to the discharge tray 4 via a discharge roller 12 which is provided immediately after the recording position and constitutes a conveying means for discharging the sheet. The discharge roller 12 is a driving roller on which one of the rollers 12a is driven and rotated, and a driven roller 12b that is driven and rotated with respect to the driving roller 12a is pressed against the driving roller with an appropriate pressure. The driven roller 12b
Since it is located on the side in contact with the recording ink, it is formed in a spur (star) shape to eliminate the offset.

(First Embodiment of the Present Invention) As described above, in the ink jet printer having the structure shown in FIG. 3, when a recording command is issued, a recording operation is started in accordance with input image data. First, the sheet P is fed through the pickup roller 5 and fed through the feed roller 6 and the first pressure roller 7. The sheet P is reversely conveyed by the feeding roller 6, and is conveyed toward the platen 9, which is a recording position, while being nipped by the second pressing roller 8.

Sheet P guided and conveyed on platen 9
When the leading end reaches the recording start position (recording section), the conveyance by the feed roller 6 is controlled to be stopped. In this state, recording scan of the ink head 10 located at the home position is started via the carriage 11, and ink ejection control is performed in accordance with image data. As a result, a recorded image corresponding to the image data by the dot ink is reproduced on the surface of the stopped sheet P.

When one scan is performed by the ink head 10, the ink head 10 is returned to the home position, and the sheet P is conveyed by the amount corresponding to the line recorded at this time and stopped. When such an operation is repeated and a recorded image corresponding to one page of image data is reproduced on the entire sheet P, the recording is terminated, and the sheet P is transferred to the discharge tray 4 via the discharge roller 12. And is prepared for recording on the next sheet.

Therefore, as described with reference to FIG. 12, when the size of the image data does not match the size of the fed sheet to be recorded and the size of the sheet P is small, the sheet P In some cases, recording is performed in a portion where no printing is performed, and ink is ejected to the platen 9 having no sheet. The unnecessary ink I adhering to the platen 9 in this way stains the back surface of the sheet P to be sent next. In order to remove the adhering ink, in the present invention, the cleaning device 20 is attached to the platen 9. It is arranged to face the opposite side to the recording position.

The cleaning device 20 is shown in FIGS.
As shown in FIG. 1, the side facing the platen 9 is a cleaning member 21 such as a cleaning blade or a felt, and is provided with a support 22 that supports the cleaning member 21 and is fixed at a predetermined position in the main body of the printer 1. . The cleaning member 2 of the cleaning device 20
Reference numeral 1 denotes a state in which the leading end portion for cleaning is separated from the platen 9 in the recording state.

In the present invention, in order to record a plurality of lines from the ink head 10 simultaneously with the cleaning device 20, the platen 9 has at least a length corresponding to the line width in a planar state. In order to guide and convey the sheet P as much as possible, an endless conveying belt 15 is provided. The transport belt 15 is stretched between two opposing rollers 16 and 17, and one stretched flat surface side faces the ink head 10 and the other flat surface side is the cleaning device. 20 are provided.

Roller 1 for Constituting the Platen 9
In 6 and 17, for example, the downstream side in the sheet conveying direction is a driving roller (16), and the upstream side is a driven roller 17. The driving roller 16 receives a driving force from a driving motor (not shown) and is driven to rotate. Driven roller 17
1 is movable in the left-right direction and is rotatably supported in FIG. 1 in order to apply an appropriate tension to the transport belt 15, and is separated from the drive roller 16 via an urging means. It is urged in the direction to be. Accordingly, stable movement and rotation can be performed in a state in which an appropriate tension is applied to the driven and rotated transport belt 15.

In the printing operation shown in FIG. 1, the platen 9 is arranged at a printing position at a predetermined interval so as to face the ink head 10 as shown in FIG. In this case, it is positioned at a recording position that is separated without contacting the cleaning member 21 of the cleaning device 20. On the other hand, when recording is not being performed, the platen 9 is movably provided at a cleaning position in contact with the cleaning member 21 of the cleaning device 20, as shown in FIG.

In particular, the platen 9 is provided with a driving roller 16 and a driven roller 17 rotatably on a support frame (not shown), and a transport belt 15 provided so as to be stretched between the rollers 16 and 17. The support frame itself is provided on the main body frame of the printer 1 so as to be vertically movable in FIG. By providing a moving mechanism for moving the support frame up and down, the platen 9 is provided so as to be movable to a cleaning position and a recording position, and can be moved to a position as required.

As shown in FIG. 5, for example, the cleaning member 21 constituting the cleaning device 20 has the entire front end in contact with the transport belt 15 of the platen 9 and lacks the front and rear portions in the moving direction of the belt 15 (a). And (b)
(C), a wiper blade structure in which the tip portion is curved and deformed as shown in (c), and a tip portion made of felt or the like as shown in (d). . In any case, when the leading end portion of the cleaning member 21 contacts the transport belt 15,
The ink I adhered to the belt 15 is removed and cleaning is performed.

In the above-described configuration, the platen 9 is at the recording position during the recording operation, after completing the initial setting after the power is turned on, and when waiting for the next recording operation, FIG. The movement is controlled as shown in FIG. When the recording operation for one page is completed, the platen 9
The platen 9 is moved to the cleaning position shown in FIG. Further, at the time of power-on, for example, the platen 9 has been moved to the position shown in FIG. 1B during the initial setting, and after being cleaned, is moved to the recording position.

The cleaning time of the platen 9 may be set to at least the time t for driving the entire circumference of the platen 9. That is, the platen 9 is at least 1
The time point is set so as to rotate more than one rotation (one round).

Then, the sheet P is fed during the recording operation, and the recording is started by scanning the ink head 10 in a state where the sheet P is conveyed to the recording section facing the ink head 10. When the recording operation on one sheet P is completed, the sheet P is discharged through the discharge roller 12. The cleaning operation is started according to the discharging process.

That is, the sheet P is discharged from the recording position to the cleaning position in order to clean the platen 9 based on the detection signal of the sheet detection sensor provided in the sheet conveying path when the sheet P is discharged. This lowering movement causes the platen 9 to come into contact with the cleaning unit of the cleaning device 20. By rotating the drive roller 16 to rotate the conveyor belt 15 at least once, the entire circumference of the surface of the platen 9 can be cleaned.

By performing the above cleaning operation,
The ink adhered to the surface of the platen 9 during the recording operation is cleaned. Then, when the cleaning operation is completed, the platen 9 is raised to the recording position, and waits for the next recording operation.

In such a configuration, the platen 9 is provided so as to be movable between the recording position and the cleaning position, and after the recording is completed, the movement of the platen 9 is controlled to the cleaning position. The platen 9 is driven by this movement, and ink and the like attached to the surface of the platen 9 are cleaned by contact with the cleaning member of the cleaning device 20 provided at the cleaning position. Therefore, the offset in which the back surface of the next sheet is stained with the ink adhering to the platen is eliminated.

In this case, in order to move the platen 9,
The driving load and weight of the ink head 10 do not increase at all, and there is no hindrance to high-speed driving. Further, since there is no cleaning configuration in which the platen 9 is pressed from the side of the carriage 11 on which the ink head 10 is mounted at the time of cleaning, there is no fear of a change or displacement of the positions of the ink head 10 and the platen 9.

(Example of Movement Control for Cleaning Platen of the Present Invention) In the above description, the execution of the cleaning operation is controlled when the recording operation is completed. Then, it has been described that the movement of the platen 9 is controlled to the recording position before the next recording operation is started.

An example of platen movement control for cleaning suitable for the present invention will be described below. Before that, in order to execute a control example described below, a detection configuration of the sheet P shown in FIG. 6 will be described.

In FIG. 6, a sheet leading edge detecting sensor 23 for detecting that the sheet P is sent to the recording section immediately before recording with ink dots by the ink head 10.
Is provided in the conveyance path of the sheet P. The sheet leading edge detection sensor 23 is provided on the upstream side in the sheet conveyance direction with respect to the area where the recording is performed by the ink head 10. In FIG. 6, the front end of the sheet P is detected by the detection sensor 23 immediately before the area where recording is performed by the ink head 10.

On the other hand, a trailing edge detection sensor 24 for detecting the trailing edge of the sheet P is provided on the downstream side in the sheet conveying direction after the recording is completed. The trailing edge detection sensor 24 detects the trailing edge of the sheet immediately after the trailing edge of the sheet on which recording has been completed has passed a recording position which is a recording area. These sensors 23 and 24 are constituted by, for example, optical sensors.

The sensors 23 and 24 are arranged to face the platen 9 for conveying and guiding the sheet P to the recording position. Therefore, if the platen 9 is made of a blackish member, the whitish sheet P to be conveyed, that is, the sheet P having a high reflectance can be easily detected, and the trailing end and the leading end can be easily and reliably detected.

Then, a recording operation is executed, and the recording on the sheet P is sequentially performed by the ink dots in the reciprocation of the ink head 10 in the direction of the arrow. The sheet P
Is controlled in accordance with the traveling control of the ink head 10, and when one page of recording is completed, a discharging process is performed.

As described above, recording (printing) as shown in FIG.
When the operation is performed (S1), the trailing edge of the sheet P passes through the recording unit (printing unit) corresponding to the ink head 10, and is detected by the trailing edge detection sensor 24 (S2).
In order to perform the cleaning process of FIG.
It is moved (down) from the recording position to the cleaning position as shown in FIG. 1B as shown in FIG. 1A (S3).
At this time, the platen 9 contacts the cleaning member 21 of the cleaning device 20.

When the platen 9 is lowered as shown in FIG. 1B, the transport belt 15 forming the platen 9 is moved.
Is rotated at least one rotation (1
Lap). Thus, if there is ink I or the like adhering to the surface of the platen 9 by the cleaning member 21, it is removed. This rotation is at least one rotation, and a plurality of rotations may be performed.
Is stopped (S4), and in this state, a standby is made (S4).
5).

During this standby period, the recording operation on the next sheet P is started, and the leading edge detection sensor 23 detects this before the sheet P is sent to the recording position (printing section) (S6). ). In response to the detection, the waiting platen 9 is driven to rise from the cleaning position to the recording position (S7). Due to the rise, the platen 9 is rotated by the traveling drive of the platen 9, that is, the rotational drive of the drive roller 16, and the sheet P is conveyed and guided to the recording position. Hereinafter, a recording operation is performed, and the above-described processing control is sequentially and repeatedly performed.

In this control example, the cleaning position of the platen 9 becomes the standby position, the recording operation is started, and the platen 9 is controlled to move to the recording position immediately before the leading edge of the sheet P is conveyed to the recording section. In such control, the sheet P
When the sheet is fed to the recording section, the tip of the sheet is not caught on the ink head 10 or the platen 9 and is smoothly conveyed and guided on the platen 9.

Further, by keeping the platen 9 at the cleaning position until the sheet P is detected by the leading edge detection sensor 23, a sufficient cleaning time can be taken and the cleaning effect can be enhanced. .

(Example of Platen Elevation Structure) As described above, the platen 9 is driven to move up and down. As such an elevating mechanism, a conventionally known technique can be used as it is. An example is shown below, but the present invention is not limited to only such a lifting mechanism.

FIGS. 8 and 9 show an example of an elevating mechanism 30 for driving the platen 9 up and down. The driving roller 16 and the driven roller 17 for stretching and driving the transport belt 15 constituting the platen 9 are shown. A mechanism is provided for holding a support frame 25 that rotatably supports.

The support frame 25 is mounted on the drive roller 16.
A guide hole 26 which is a long hole for guiding vertical movement is formed, and a guide shaft 27 is provided so as to pass through the guide hole 26. The guide shaft 27 is fixed to a frame (not shown) of the printer body, regulates the vertical movement of the support frame 25, and guides the movement in a stable state.

The support frame 25 is provided with a concave portion 28 at the bottom for driving up and down. In the concave portion 28 of the support frame 25, a support roller 32 provided at the tip of a support piece 31, which is a mechanism for holding the above-described support frame, is positioned and holds the support frame 25. The support rollers 32 are rotatably provided on the support piece 31 and hold the support frame 25 at four locations.

The support piece 31 is provided with a rotation fulcrum shaft 33 at a lower portion, and the front and rear (upstream and downstream sides in the sheet conveying direction) in FIG. The link member 34 is rotatably supported by the support piece 31, and the rotation fulcrum shaft 33 is provided on the above-described printer frame (not shown). In addition, the front and rear support pieces 31
As shown in FIG.
Has been fixed.

As described above, the support frame 25 is
It is held by one support roller 31. Since the support pieces 31 are connected to each other by the link members 34 at the front and rear, for example, in FIG. 8, when the counterclockwise rotation is performed, the position of the support rollers 31 is lowered, and the support frame 25 is moved.
Is guided by the guide shaft 26 and descends downward.

Therefore, as a mechanism for rotating the support piece 31, a cam 36 is provided so as to abut one side surface of the support piece 31. The cam 36 is driven to rotate by a driving motor (not shown). Therefore, cam 3
6 is rotated counterclockwise in FIG. 8, and the support piece 31 is pushed at the tip far away from the rotation axis.
The support piece 31 is rotated counterclockwise about a rotation fulcrum shaft 33. Thereby, all the support pieces 31 are simultaneously rotated counterclockwise by the link member 34 and the coupling member 35.

A spring 37 for urging the support piece 31 clockwise is provided on the support piece 31 side opposite to the support piece 31 on which the cam 36 is arranged to face. The spring 37 secures a biasing force of a magnitude that should normally hold the support frame 25 at the position shown in FIG. Therefore, the clockwise rotation of the cam 36 urges the support piece 31 to rotate clockwise so that the support piece 31 always contacts the peripheral surface of the cam 36.

As described above, the elevating mechanism 30 includes the support frame 25 and a mechanism for holding and elevating the support frame 25, and controls the rotation of the cam 36 to move the support frame 25 up and down. Then, the platen 9 is moved up and down. 8, if the cam 36 is rotated counterclockwise against the urging force of the spring 37, as described above, the platen 9 is lowered.

Thus, the transport belt 15 of the platen 9
Cleaning device 20 is fixed to the body frame
Abuts on the cleaning member 21. In this state, the drive roller 16 is driven to rotate, so that the transport belt 15 is cleaned.

A driven gear 29 is provided on a rotating shaft of the driving roller 16 as shown in FIG. 9 in order to rotate the driving roller 16. The driven gear 29 is transmitted with rotational force from a drive motor, which is a drive unit (not shown), via a drive gear, various idle gears, and the like. In particular, since the drive roller 16 needs to be driven to rotate at the cleaning position and the recording position, a drive motor is simultaneously mounted on the support frame 25, and a drive gear directly connected to a rotation shaft of the drive motor and the driven gear are provided. The gear 29 is connected via a gear. Accordingly, since the drive motor is provided on the support frame 25 side, the transport belt 15 can be driven regardless of the position where the platen 9 is moved.

(Another Driving Example for Traveling and Driving Platen 9) The driving roller 16 for traveling and driving the transport belt 15 constituting the platen 9 is supported by the support frame 25.
It is driven using a drive motor provided on the side. Therefore, the pickup roller 5, the feed roller 6,
Further, it is provided separately from the driving motor of the sheet conveying system for driving the paper discharge roller 12 and the like.

Therefore, in this driving example, the drive motor of the transfer means of the transfer system including the feed roller 6 and the discharge roller 12 can be used also as the platen drive motor provided on the support frame 25 described above. The drive mechanism will be exemplified. This is for the purpose of reducing the number of drive motors and simplifying the drive system. A single drive motor can convey and discharge sheets, furthermore, drive the platen 9 and drive during cleaning. Is what you do.

FIGS. 10 and 11 show the configuration of the drive system. FIG. 10 is a plan view of the driving unit, and FIG. 11 is a side view of FIG. The drive motor 39 constituting the drive means is
For example, a driven gear 29 having a rotation shaft of the drive roller 16 fixedly engaged with a drive gear 40 provided on the support frame 25 and fixed (directly connected) to the rotation shaft of the drive motor 39. Thus, when the drive motor 39 is rotated, the drive roller 16 is driven to rotate.

The driven gear 29 includes driven gears 43 and 44 fixed to the rotating shafts of the feed roller 6 and the discharge roller 12a, for example, on both sides of the driven gear 29 via idle gears 41 and 42. Has been engaged. In this case, when the support frame 25 is in a state where the platen 9 is moved upward to the recording position as shown in FIG.
Is connected to the feed roller 6 and the paper discharge roller 12a, and the rotational force is transmitted. Therefore, the drive motor 39 controls not only the drive of the platen 9 but also the feed roller 6,
The discharge roller 12a can be driven.

Further, the driven gear 43 has a double gear structure, and is driven by another driven gear (not shown) provided, for example, on the rotating shaft of the pickup roller 5 constituting the conveying means via another idle gear 45. ). Thus, the drive of the pickup roller 5 can also be controlled by the same drive motor 39. Here, although not shown,
In particular, the pickup roller 5 is configured to be driven by one rotation, and the rotation drive is controlled via a clutch or the like to perform the rotation drive when necessary.

Other feed rollers 6 and discharge rollers 12a
And the like are rotated in synchronization with the driving of the platen 9, so that there is no problem even if the rotation or stop control is performed at the same time. However, if it is necessary to independently perform rotational drive control, a clutch or the like for controlling transmission of rotational force may be provided.

Then, when the recording operation is completed and the cleaning process of the platen 9 is performed, the platen 9 is lowered together with the support frame 25 constituting the elevating mechanism 30 as described above. Therefore, the drive motor 39 and the drive gear 40 provided on the support frame 25 and the driven gear 29 of the drive roller 16 are simultaneously lowered. As shown in FIG. 11B, the driven gear 29 is disengaged (disengaged) from the idle gears 41 and 42 provided on both sides as the platen 9 descends. Therefore, the drive motor 39 is rotated only by the platen 9 alone, particularly only the transport belt 15, so that the platen 9 is driven to run and the feed roller 6 and the discharge roller 12a are not rotated. Therefore, during the cleaning process, only the platen 9 is driven, and the feeding roller 6 and the like are not rotated needlessly.

In such a configuration, the platen 9 is positioned at the recording position in a standby state. That is, when the recording operation is started, the platen 9 is at the recording position, and in this state, the drive motor 39 is driven to rotate,
Sheet P can be fed. Then, when the recording operation is completed and the rear end of the sheet P has passed the recording section, the platen 9 is lowered for cleaning, and cleaning is performed. At this time, the transport belt 1 forming the platen 9
5 is only driven to rotate, the sheet feeding and the conveyance driving are not performed, and the cleaning process is performed.

When the cleaning process is completed, the platen 9 is driven up to execute the next recording operation, and waits at the recording position. As a result, the next sheet can be fed and conveyed, and the recording operation on the sheet can be executed.

In the description of the embodiment of the present invention,
Although the example in which the platen 9 is configured by providing the endless conveying belt 15 has been described, it is needless to say that the platen 9 may be of a roll shape. In the platen 9 having such a shape, the unnecessary ink I attached to the platen 9 can be removed by the cleaning device 20 which is similarly provided so as to be movable to the recording position and the cleaning position and is fixed.

Further, according to the configuration of the platen 9 described in the embodiment of the present invention, the cleaning member 21 comes into contact particularly on the side opposite to the recording portion of the transport belt 15. Therefore, the drive roller 16 and the like
If pressure contact is not performed at step 1, the shaft and the like of the drive roller 16 will not be deformed or displaced, and the positional relationship between the ink head 10 and the platen 9 at the recording position can be prevented from being disrupted.

[0086]

The ink jet printer provided with the cleaning device of the present invention described above is located at the recording section.
A platen for guiding the recording medium and the like is provided so as to be movable between a recording position and a cleaning position, and can be moved to the cleaning position after recording so that cleaning can be performed. The problem that the side is stained with ink can be eliminated.

The movement of the platen to the cleaning position is performed when the recording section has passed the rear end of the recording medium, so that the recording operation is not hindered until the start of the recording operation on the next recording medium. Cleaning can be performed using

Further, the timing for moving the platen to the recording position is performed when the leading end of the recording medium is detected shortly before reaching the recording section, so that the leading end of the recording medium is not caught and the recording medium is smoothly moved to the recording section. You will be able to be guided to

Further, when the platen is driven to rotate for cleaning, it is rotated at least once,
Adhesion of ink can be satisfactorily removed. Further, by providing a driving means on the platen side and connecting the paper feeding and conveying means of the recording medium and the driving means at the recording position, only the platen is used at the time of cleaning, and the other is provided at the time of recording. The paper feeding and conveying means can be driven, and the object of the present invention can be achieved with one driving means.

As described above, according to the cleaning device of the present invention, it is not necessary to provide a cleaning device on the ink head side, so that it does not hinder high-speed scanning of the ink head and avoids increasing in that direction. It can be executed without any trouble in recording.

[Brief description of the drawings]

FIGS. 1A and 1B are plan views showing a configuration including a cleaning device in a recording unit in an ink jet printer of the present invention, wherein FIG. 1A shows a recording state, and FIG. 1B shows a cleaning state.

FIG. 2 is a perspective view of a recording unit including a cleaning device in the inkjet printer shown in FIG.

FIG. 3 is a configuration diagram schematically showing an internal structure of the ink jet printer according to the present invention.

FIG. 4 is a perspective view showing the appearance of the inkjet printer in FIG.

FIG. 5 is a plan view showing various examples of a cleaning member for constituting the cleaning device according to the present invention.

FIG. 6 is a top view of a recording unit showing a configuration example for controlling a platen cleaning process according to the present invention.

FIG. 7 is a flowchart illustrating an example of a control procedure of a platen cleaning process in the configuration illustrated in FIG. 6;

FIG. 8 is a plan view showing an example of an elevating mechanism for moving a platen to a recording position and a cleaning position according to the present invention.

FIG. 9 is a side view of the lifting mechanism shown in FIG. 8;

FIG. 10 is a plan view showing an example of a drive configuration for driving a platen according to the present invention.

FIG. 11 shows a platen driving mechanism shown in FIG.
This is for describing the driving state at the recording position and the cleaning position, and (a) shows the driving state at the recording position and (b)
FIG. 6 is a diagram illustrating a driving state at a cleaning position.

FIG. 12 is a diagram illustrating a state in which a platen is stained with unnecessary ink in a conventional inkjet printer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ink-jet printer 3 Paper supply cassette (paper supply part) 4 Discharge tray 5 Pickup roller (paper supply means) 6 Paper supply roller (conveyance means) 9 Platen 10 Ink head 12 Discharge roller (conveyance means) 15 Transport belt 16 Drive roller 17 Driven roller 20 Cleaning device 21 Cleaning blade (cleaning member) 23 Detection sensor (for detecting front end) 24 Detection sensor (for detecting rear end) 29 Driven gear 30 Lifting mechanism 39 Drive motor (drive means) 40 Drive gear (drive means) I Unnecessary ink P sheet (recording medium)

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Masanori Yamada 22-22, Nagaike-cho, Abeno-ku, Osaka-shi, Osaka F-term (reference) 2C056 EA16 EB13 EB44 EC03 EC12 EC23 EC34 HA28 HA29 HA34 HA60 JB18 2C061 AQ05 CM06 CM14 CM18

Claims (7)

[Claims] 1. A platen for guiding a recording medium to a recording unit facing an ink head that discharges ink is provided, and a platen is provided on a side opposite to the side facing the ink head with respect to the platen. A cleaning device provided with a cleaning member for cleaning the surface of the platen, which is positioned in a state where the platen is in contact with the ink head, at a recording position facing the ink head at a fixed interval, and in contact with the cleaning member. An ink jet printer provided with a cleaning device movably provided to a cleaning position to be cleaned. 2. A rear end detection sensor for detecting that a recording medium passes through a recording section facing the ink head,
2. The ink jet printer according to claim 1, wherein the platen is moved to a cleaning position when the trailing edge of the recording medium is detected by the trailing edge sensor. 3. A detection unit for detecting a leading end of the recording medium before a recording medium is guided to a recording unit facing the ink head, wherein the leading end detection sensor detects the leading end of the recording medium, and causes the platen to detect the leading end of the recording medium. 2. An ink jet printer comprising the cleaning device according to claim 1, wherein the ink jet head is moved to a recording position at a predetermined distance from the ink head. 4. An ink jet printer provided with a cleaning device according to claim 1, wherein a driving means for driving said platen is provided on said platen side. 5. A driving unit for driving the platen is provided on the platen side, and the conveying unit for conveying a recording medium to a recording unit in a state where the platen is positioned at a recording position, comprises: 2. An ink jet printer having a cleaning device according to claim 1, wherein said ink jet printer is configured so as to be disconnected from said transport means when connected to a driving means and positioned at a cleaning position. 6. The apparatus according to claim 4, wherein the driving means drives the platen to rotate at least one turn while the platen is positioned at the cleaning position.
Or an inkjet printer provided with the cleaning device according to 5. 7. The printing apparatus according to claim 1, wherein the platen is rotated at least one or more times while being positioned at the cleaning position, and then moved to a recording position to feed a next recording medium to a recording unit. An ink jet printer comprising the cleaning device according to claim 5, wherein the ink jet printer is in a standby state.