JPH11254708A - Ink-jet recording apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary wiping mechanism which can secure an invasion amount of a wiper blade to a recording head at a proper value stably and highly accurately, and maintain the invasion amount of the wiper blade constant even when a height of a carriage is switched. SOLUTION: This apparatus includes a rotating means for rotating a wiper blade 10, a lift means for oscillating thereby moving a wiper unit 302 up, down, a butt roller 11 butting in touch with a guide face of a carriage 200 and an urging spring 12 for pressing the butt roller 11 to the guide face. An axis of an oscillation shaft 6 of the wiper unit 302 is made to be common with an axis of a rotary shaft of the rotating means.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus which performs recording by discharging ink from a recording means onto a recording medium.

[0002]

2. Description of the Related Art A recording device having a function such as a printer, a copying machine, a facsimile, or a recording device used as an output device such as a composite electronic device including a computer or a word processor, or a workstation, records on the basis of recording information. The image (including characters and symbols) is recorded on a recording medium such as a sheet of paper or a plastic thin plate. The recording apparatus can be classified into an ink jet type, a wire dot type, a thermal type, a laser beam type and the like according to a recording method.

In a serial type recording apparatus that performs recording while performing main scanning in a direction crossing the recording medium conveyance direction (paper feeding direction, sub-scanning direction), recording means (recording head) that moves along the recording medium. The image is printed (main scanning), and after the printing of one line is completed, a predetermined amount of paper feed (pitch conveyance as sub-scanning) is performed, and then the image of the next line is again printed on the stopped recording medium. Recording (main scanning)
By repeating this operation, recording is performed in a desired range of the recording medium. On the other hand, in a line type printing apparatus that prints only by sub-scanning in the transport direction of the printing medium, the printing medium is set at a predetermined printing position,
A predetermined amount of paper feed (pitch feed) is performed while continuously printing the rows, and an image is printed in a desired range of the print medium.

Among them, an ink jet type recording apparatus (ink jet recording apparatus) performs recording by ejecting ink from a recording means (recording head) to a recording medium. High-definition images can be recorded at high speed, and can be recorded on plain paper without requiring special processing.The running cost is low and the non-impact method reduces noise,
In addition, there is an advantage that it is easy to record a color image using various types of inks (for example, color inks).

[0005] In particular, an ink jet type recording means (recording head) for discharging ink by using thermal energy,
Through a semiconductor manufacturing process such as etching, vapor deposition, sputtering, etc., an electrothermal converter, an electrode,
By forming the liquid path wall, the top plate, and the like, it is possible to easily manufacture a device having a high-density liquid path arrangement (discharge port arrangement), and to further reduce the size. Further, by utilizing the advantages of the IC technology and the micromachining technology, it is easy to make the recording means longer and more planar (two-dimensional), and it is also easier to make the recording means full-multi and high-density mounting. .

There are various requirements for the material of the recording medium. In recent years, developments have been made to meet these requirements, and paper (including thin paper and processed paper) which is a general recording medium has been developed.
In addition to paper and resin thin plates (OHP and the like), recording devices using cloth, leather, nonwoven fabric, metal, or the like as a recording medium have come to be used.

In the above ink jet recording apparatus,
Recording is performed by discharging ink from fine discharge ports formed on the discharge surface of the recording head. If foreign matter such as fixed ink, paper dust, or ink droplets adheres to the discharge surface, discharge failure (including non-discharge) Therefore, the ejection surface of the recording head is normally cleaned regularly or at a predetermined timing. Regarding the cleaning of the ejection surface in a conventional ink jet recording apparatus, various configurations are described in, for example, JP-A-6-340082, JP-A-7-9664, and JP-A-7-52396.

FIG. 8 is an external perspective view of the ink jet recording apparatus, and FIG. 9 is a perspective view showing a state where an upper cover of the ink jet recording apparatus of FIG. 8 is removed. FIG.
9, a manual insertion slot 88 is provided on the front surface of the ink jet device 100, and a roll unit 89 that can be opened and closed on the front surface is provided below the ink insertion device 100. Unit 89
Is supplied to the recording unit. Inkjet device 100
A stacker 90 for stacking a recording medium such as a discharged recording sheet; a main body 190 supported by the two legs 180;
Transparent, openable and closable upper cover 91
It has. An operation panel 120, a supply / recovery unit 300, and an ink tank 130 are provided on the right side of the apparatus main body 190 in the figure.

In FIG. 9, an ink jet recording apparatus 1
Reference numeral 00 denotes a conveying roller pair 110 for conveying a recording medium 101 (see FIG. 5) such as recording paper in the direction of arrow B (sub-scanning direction), and the width direction of recording paper 101 (direction of arrow A, main scanning). ), A carriage motor (not shown) and a belt transmission means 270 for reciprocating the carriage 200 in the direction of arrow A, and a recording means mounted on the carriage 200 as a recording means. Recording head 201 and carriage 200
Sub-tank 501 as ink storage means mounted on
(See FIG. 10), and the suction type supply / recovery unit 300 for supplying ink to the sub tank 501 and eliminating ink discharge failure due to clogging of the discharge port of the recording head 201.

In the illustrated ink jet recording apparatus, a plurality of recording heads 201 for performing color recording on recording paper 101 (hereinafter, recording paper is an example of a recording medium) are mounted on a carriage 200. Have been. The plurality of recording heads 201 include, for example, six recording heads 201 each corresponding to a different color ink, such as a Y (yellow) head, an M (magenta) head, a C (cyan) head, and a Bk ( Black) head,
A head for light C (light cyan), a head for light M (light magenta), and｝. With the above configuration, the recording paper 10
1, the recording paper 101 is conveyed to a predetermined recording start position by the conveyance roller pair 110, and then the main scanning by the recording head 201 and the conveyance roller 110
Is repeated on the recording paper 101 to perform recording.

That is, the carriage 200 is driven by the carriage belt 270 and a carriage motor (not shown).
Moves in the direction of arrow A in FIG.
01 is recorded. When the carriage 200 is returned to the position before the main scanning, the recording paper 101 is conveyed by the conveying roller pair 110 in the sub-scanning direction (the direction of arrow B in FIG. 9), and then again in the direction of the arrow A in FIG. Carriage 2
By performing the main scanning of 00, images, characters, and the like are recorded on the recording paper 101. When the above operation is repeated and the recording of one sheet of the recording paper 101 is completed,
The recording paper 101 is discharged into the stacker 90, and the recording of one sheet is completed.

FIG. 10 is an ink flow path diagram of the ink jet recording apparatus. In FIG. 10, the carriage 200 is provided with a plurality of sub-tanks 501 corresponding to a plurality of ink colors used by the plurality of recording heads 201. Each ink tank 13 corresponding to each sub tank 501
0 are connected to each other by one ink tube 502. Ink is supplied from each ink tank 130 to a corresponding sub-tank 501 through each ink tube 502. Each sub-tank 501 is connected to a negative pressure generating means provided in the supply / recovery unit 300 through a respective suction tube 503. In the illustrated example, a tube pump 504 that sends out ink by generating a negative pressure by changing the volume in a flexible tube is used as the negative pressure generating means.
In the illustrated example, the sub tank 50 is moved from the ink tank 130 to the sub tank 50.
Tube pump 504a for supplying ink to
And a tube pump 504b for suctioning ink from a discharge port of the recording means 201 is used. The ink tube 502 and the suction tube 503 are all bundled together by a caterpillar 260 so that the ink tube 502 and the suction tube 503 do not move when the carriage 200 reciprocates.

In the above-described ink jet recording apparatus, in order to prevent deterioration of recording quality due to clogging of the discharge port of the recording head 201, the discharge port surface of the recording head (the front surface provided with the discharge port) is covered with a cap. The cap 508 is covered and capping is performed, and the negative pressure generating means is operated in the capping state to make the inside of the cap 508 a negative pressure, thereby sucking ink from the discharge port and drawing new ink to the discharge port. Processing is performed. The waste ink sucked into the cap is sent to a waste liquid tank 510 through a cap tube (waste ink tube) 509.

During recording or after the suction recovery process, ink droplets adhere to the periphery of the discharge port to become wet, and the ink discharged from the discharge port is attracted to the adhered ink on the discharge port surface. The ink ejection direction becomes unstable, and a recording defect (distortion) may occur. In order to eliminate such a recording failure, it is necessary to perform a process of removing the ink adhering to the periphery of the ejection port by securely wiping (wiping and cleaning) the periphery (ejection surface) of the ejection port.

The suction recovery operation and the wiping operation will be described with reference to FIG. In FIG. 10, a cap (head cap) 508 for covering the discharge port surface is provided.
Is provided for each recording head 201. At the time of non-printing when the carriage 200 is at the home position (the right side in FIG. 9), the cap 508 is joined (contacted) to the print head 201 by a lifting means (not shown) and capping is performed, so that the print head 201 is moved. This prevents ejection failures caused by thickening and sticking of the ink due to evaporation of the ink in the ejection openings. Each head cap 508 is connected to a tube pump 504b for suction recovery through a cap tube 509.

When the suction recovery tube pump 504b is driven in the above capping state, ink sucked from the recording head 201 flows in the direction of arrow E in FIG. Ink discharge can be recovered. At the same time, the ink in the sub-tank 501 flows into the print head 201 through the head tube 507, and the print head 201 is filled with sufficient ink to be in a printable state. The downstream side (discharge side) of the ink supply tube pump 504a and the suction recovery tube pump 504b is connected to a waste liquid tank 510 for collecting waste liquid.
Sent to 0.

FIGS. 11A and 11B are a plan view and a front view of a conventional supply / recovery unit 300 in an ink jet recording apparatus, and FIGS. 12A and 12B are supply / recovery units of FIG. FIGS. 13A and 13B are a plan view and a front view of a wiper unit (wiping mechanism) provided in the recovery unit 300. FIGS. 13A and 13B show a wiper unit of FIG. It is a front view which shows the operation | movement (wiping). Next, the configuration and operation of the wiper unit will be described with reference to these drawings. In FIG. 11, reference numeral 300 denotes a supply / recovery unit disposed on the right side of the apparatus main body, 40 denotes a side plate of the supply / recovery unit 300, 45 denotes a carriage shaft attached to the apparatus main body, 46 denotes a side plate of the apparatus main body, and 47 denotes a side plate of the apparatus main body. The base plate of the supply / recovery unit 300;
The carriage 201 which has been moved to the home position (capping position) while being guided and supported by
Recording head (recording means) mounted (mounted) on 00, 3
Reference numeral 01 denotes a wiper unit provided in the supply / recovery unit 300.

In the wiper unit 301 shown in FIG. 12, 145, 147 and 149 are wiper blades 1
A wiper gear A, a wiper gear B, and a wiper gear C that constitute a gear train for transmitting a rotational force to zero. Rotation from a drive motor (not shown) is transmitted to the wiper rotation shaft 150 via these wiper gears. In addition,
A drive switching clutch (not shown) is provided in the middle of this rotation transmission, and the transmission and release of rotation from the drive motor (not shown) can be switched by the drive switching clutch.

The wiper rotating shaft 150 is rotatably supported by a wiper case 160, and the wiper rotating shaft 15
At 0, a wiper blade holding member 171 is fixed. The wiper case 160 has a substantially box shape,
It is fixed to the side plate 40 of the supply / recovery unit 300. The wiper blade 10 is formed in a thin plate shape using an elastic member such as rubber, and a plurality of (six) recording heads 2 are provided.
01 is sequentially wiped in the moving direction of the carriage 200 (the direction perpendicular to the arrow B direction in FIG. 9). In the illustrated example, the wiper blades 10 are attached to the wiper blade holding member 171 fixed to the wiper rotating shaft 150 at three locations at equal intervals in the circumferential direction. The wiper blade holding member 171 is provided with a sensor flag 171a, and the rotation phase of the wiper blade 10 can be detected by detecting the sensor flag 171a with a wiper sensor 172 fixed to the wiper case 160. ing.

The wiper sensor 172 is composed of, for example, an LED as a light emitting element and a phototransistor as a light receiving element, and generates a signal from the phototransistor in accordance with the transmission or blocking of light by the rotation position of the sensor flag 171a. It is configured as follows. The phase of the wiper blade 10 can be detected from this signal. At a predetermined position of the wiper case 160, a blade cleaner 173 formed of an ink absorber is provided (fixed). This blade cleaner 173
Is for removing (cleaning) foreign matters such as ink droplets adhered to the wiper blade 10 by contacting the tip of the wiper blade 10.

Next, the wiper unit 301 having the above-described structure is used.
Will be described. When the drive switching clutch (not shown) is turned on and the drive motor is rotated, the rotation is transmitted to the wiper blade holding member 171 via the gear trains 145, 147, 149 and the wiper rotating shaft 150, and is attached to the holding member 171. The wiper blade 10 is rotated in the direction indicated by an arrow in FIG. Then, the drive motor is stopped at a position where the wiper sensor 172 detects the sensor flag 171a, and the drive switching clutch is turned off.

Therefore, the carriage 200 on which the recording head 201 is mounted moves at a constant speed from the home position (the right side position shown in FIG. 11) in the direction indicated by the arrow in FIG. 13, and the wiper blade 10 is moved in synchronization with the movement. Rotate at a constant speed in the direction of the arrow. The moving speed and rotation speed of the carriage 200 and the wiper blade 10 and the distance M at the start of rotation are set in advance so that the tip of the wiper blade 10 abuts on the periphery of the ejection opening of the recording head 201. By the contact, the ejection port surface of each recording head 201 can be wiped as shown in FIG.
As shown in FIG. 13, three wiper blades 10 are provided at equally-spaced positions in the circumferential direction of the wiper blade holding member 171, and three prints are made by one rotation (one rotation) of the wiper rotation shaft 150. The head 201 can be wiped. That is, in the illustrated configuration example, the wiper rotating shaft 15
When 0 is rotated twice (two rounds), six recording heads 201 are formed.
It is configured to wipe all of.

The tip of the wiper blade 10 comes into contact with the blade cleaner 173 so that ink droplets and the like adhering to the wiper blade 10 can be removed. When the wiping operation is not performed, the state shown in FIG. 13A, that is, the state in which the wiper sensor 172 detects the sensor flag 171a of the wiper blade holding member 171 is held, and the wiper blade 10 I will not touch you. in this way,
A rotary wiping mechanism using a rotary wiper is particularly effective when the number of recording heads 201 is large. The reason is that it is not necessary to provide the wiper blades 10 by the number of recording heads 201. In the wiper unit 301 (wiping mechanism), the recording head 20
Before wiping 1, the wiper blade 10 is cleaned by the cleaner 173, so that good wiping performance can always be ensured.

[0024]

FIGS. 14A and 14B are schematic diagrams showing a wiped state of the wiper blade 10 when the ejection opening surface of the recording head 201 is being wiped. The wiper blade 10 exerts the most excellent wiping effect (wiping effect) when it comes into contact with the recording head 201 moving in the direction indicated by the arrow at the tip end as shown in FIG. Yes, this has been confirmed by experiments. on the other hand,
As shown in FIG. 14B, when the antinode portion of the wiper blade 10 is in sliding contact with the discharge port surface of the recording head 201, a sufficient wiping effect cannot be obtained. In addition, as shown in FIG.
In the state where the antinode portion is in sliding contact with the discharge port surface, the wiper blade 10 is strongly pressed against the discharge port surface of the recording head 201, so that the discharge port surface is easily damaged, and the discharge port is required to ensure durability. It is necessary to improve the strength of the outlet surface, which causes a problem that the cost is significantly increased. Therefore, the recording head 2 of the wiper blade 10
01 (its ejection port surface), the penetration amount (overlap amount)
It is an important factor that determines the wiping performance, and it is necessary to position it with high accuracy.

However, in the configuration of the wiping mechanism (wiper unit) as shown in FIGS. 11 and 12,
The amount of intrusion of the wiper blade 10 can be determined by simply adding the component tolerances to the recording head 201 → carriage 200 →
Carriage shaft 45 → side plate 46 of the apparatus main body → base plate 47 of supply / recovery unit 300 → supply / recovery unit 30
0 side plate 40 → wiper unit (wiping mechanism) 3
Since the tolerances of the component No. 01 → the wiper blade 10 are gathered, it is quite difficult to stably secure the accuracy of the penetration amount. Therefore, a method has been adopted in which the wiper blade 10 is separated into two parts to adjust the amount of intrusion of the wiper blade 10. However, in this case, the work of adjusting the amount of intrusion is still complicated,
In addition, there is a problem that the cost is increased.

The distance between OHs due to the difference in thickness of the recording medium (recording paper) 101 (the gap between the recording medium and the recording head,
In order to absorb the change in the distance between sheets, the carriage 200
Is provided. FIG. 15 is a schematic perspective view showing the configuration of the height switching mechanism. In FIG. 15, a carriage roller 200a whose position (height) is adjustable in the direction of the arrow is attached to the carriage 200, and the position of the carriage roller 200a is adjusted in the direction of the arrow with respect to the carriage shaft 45, whereby the carriage 2 is moved.
00 in the direction of the arrow about the carriage shaft 45,
It is configured to switch the distance between OHs. However, in the configuration of the wiping mechanism (wiper unit) as shown in FIGS.
By switching the height to zero, the wiper blade 10
Is deviated from an appropriate value, and the wiping performance of the wiper blade 10 is deteriorated as described above.

The present invention has been made in view of such a technical problem, and an object of the present invention is to provide a rotary wiping mechanism capable of stably and accurately adjusting an amount of a wiper blade entering a recording means. Can be secured,
Even when the height of the carriage is switched, the amount of intrusion of the wiper blade can be kept constant, and a wiping operation that can reliably remove ink adhering to the ejection port surface of the recording head can be realized. An object of the present invention is to provide an ink jet recording apparatus capable of eliminating deterioration.

[0028]

According to a first aspect of the present invention, in order to achieve the above object, recording is performed by discharging ink from a recording means to a recording medium, and a plurality of wiper blades are rotated in the moving direction of the recording means. In an ink jet recording apparatus that wipes the ejection port surface of the recording means by causing
Rotating means for rotating the wiper blade, elevating means for elevating and lowering the wiper unit by swinging, an abutting member abutting on a guide surface of the carriage, and an urging means for urging the abutting member against the guide surface, And the swing center of the wiper unit is made common to the axis of one rotation shaft of the rotation means. According to a second aspect of the present invention, in addition to the configuration of the first aspect, the rotating means and the lifting / lowering means are configured to be driven by switching the drive of the same drive source, thereby achieving the object more efficiently. It is.

[0029]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a partially cutaway perspective view showing an embodiment of an ink jet recording apparatus to which the present invention is applied. The recording operation such as the carriage operation and the recording medium transport operation and the configuration for the inkjet recording apparatus 100 in FIG. 1 and the suction recovery operation of the supply / recovery unit 300 and the configuration therefor will be described with reference to FIGS. It is substantially the same as what was done. Therefore, FIG.
The configuration and operation of the ink jet recording apparatus described in FIG. 15 are described below in the embodiment of the invention (particularly,
Except for the wiper unit as the wiping mechanism), the embodiment of the ink jet recording apparatus to which the present invention is applied is directly used. Accordingly, the ink jet recording apparatus shown in FIG.
And the same or corresponding portions as those in FIGS. 8 to 15 are denoted by the same reference numerals, and detailed description thereof will be omitted.

FIGS. 2A and 2B are plan views showing a state in which the carriage 200 has moved to a home position on the supply / recovery unit 300 in an embodiment of the ink jet recording apparatus to which the present invention is applied. It is a front view. 2, reference numeral 40 denotes a left side plate of the supply / recovery unit 300, reference numeral 1 denotes a step motor which is a drive source of the supply / recovery unit 300, and a portion surrounded by a broken line in FIG. A wiper unit (wiping mechanism) forming a part of the recovery unit 300; The wiper unit 302 is a portion corresponding to the wiper unit 301 in FIG.

A recording means (recording head) 201 mounted (mounted) on the carriage 200 applies ink in accordance with a recording signal, thereby selectively discharging ink from a plurality of discharge ports for recording. Head. The recording head 201 is an ink jet recording unit that discharges ink by using thermal energy, and includes an electrothermal converter for generating thermal energy. Further, the recording head 201 includes:
The recording is performed by discharging ink from the discharge ports by utilizing a pressure change generated by growth and shrinkage of bubbles caused by film boiling caused by the heat energy applied by the electrothermal transducer. The electrothermal transducer is provided corresponding to each of the ejection ports, and discharges ink from the corresponding ejection port by applying a pulse voltage to the corresponding electrothermal transducer in accordance with a recording signal.

FIG. 7 is a partial perspective view schematically showing the structure of an ink ejection section (one ejection port array) of the recording means (recording head) 201. In FIG. 7, a plurality of ejection openings 82 are arranged at a predetermined pitch on an ejection surface 81 facing a recording material (recording paper or the like) with a predetermined gap (for example, about 0.3 to 2.0 mm). Are formed, and an electrothermal converter (heating resistor, etc.) 85 for generating energy for ink discharge is provided along the wall surface of each liquid path 84 communicating the common liquid chamber 83 and each discharge port 82. Have been. Recording head 201
Is that the ejection port 82 is moved in the main scanning direction (the carriage 20
In the present embodiment mounted on the carriage 200, the carriage 200 is guided and supported in a positional relationship so as to be aligned in a direction crossing the moving direction of the carriage 200). In this manner, the corresponding electrothermal transducer 85 is driven (pulse voltage is applied) based on the image signal or the ejection signal to cause the ink in the liquid path 84 to boil, and the pressure generated at that time causes the ink from the ejection port 82 to pass through the ejection port 82. A recording unit (recording head) 201 for discharging droplets is configured.

FIGS. 3A, 3B and 3C are a plan view, a front view and a longitudinal sectional view, respectively, of the wiper unit 302 in FIG. That is, (b) of FIG. 3 is a front view as viewed from the line bb in (a) of FIG. 3, and (c) of FIG. 3 is taken along line cc in (b) of FIG. FIG. FIG.
2, reference numeral 2 denotes a wiper gear (A) which is driven to rotate by the step motor 1 in FIG. 2 (a). For this wiper gear (A), the rotation of the step motor 1 is a gear train (not shown). And transmitted via the drive switching clutch.
The drive switching clutch has, for example, a gear portion, an electromagnetic coil portion, and a rotating shaft. When a current flows through the electromagnetic coil portion, the rotation of the gear portion is transmitted to the rotating shaft, and the current of the electromagnetic coil portion is also transmitted. When the gear is turned off, only the gear portion idles.

The wiper gear (A) 2 meshes with a wiper gear (B) 3 having a bevel gear. The wiper gear (B) 3 is rotatably supported by a swing shaft 6 fixed to a side plate 40 of the supply / recovery unit 300. The bevel gear portion of the wiper gear (B) 3 meshes with a wiper gear (C) 4 composed of a bevel gear. By the wiper gears 3 and 4 having bevel gears, the rotation direction is changed to a substantially right angle direction. A wiper rotating shaft 5 is fixed to the center of the wiper gear (C). The swing shaft 6 is fixed to the side plate 40. The swing shaft 6 rotatably supports the wiper gear (B) 3 and also rotatably supports a wiper bearing 7. The wiper bearing 7 is fixed to a substantially box-shaped wiper case 8. Therefore, the wiper case 8
Is supported by the wiper bearing 7 so as to be swingable about the swing shaft 6.

The wiper rotating shaft 5 is rotatably supported by the wiper case 8. Further, the wiper case 8 is provided with a cam contact portion 8a with which the elevating cam 13 formed of a rotating member contacts. A blade holder 9 is fixed to the wiper rotation shaft 5. A wiper blade 10 is fixed to the blade holder 9. The blade holder 9 is provided with a sensor flag 9a. The sensor flag section 9 a is for detecting the rotation phase of the blade holder 9 in cooperation with the wiper rotation sensor 14.

The wiper blade 10 is formed of an elastic member such as rubber in the form of a thin plate as in the prior art, and the ejection port surface 81 of the recording head 201 is arranged in the recording head arrangement direction (indicated by an arrow B in FIG. 1). A direction perpendicular to the recording paper transport direction,
In other words, it wipes in the direction of movement of the carriage 200). In the present embodiment, three wiper blades 10 are mounted at equally spaced positions in the circumferential direction of the blade holder 9 that is driven to rotate. Reference numeral 11 denotes a contact roller. The contact roller 11 is rotatably supported by a shaft provided on the wiper case 8. Reference numeral 12 denotes an urging spring. The biasing spring 12 is a tension spring having one end connected to the wiper case 8 and the other end connected to a cutout (not shown) of the side plate 40. It is urged in the direction of arrow Z in FIG. 13
Is a lifting cam. The elevating cam 13 can be driven to rotate in the direction of arrow P in FIG. 3C by the rotational force transmitted from the step motor 1 via a gear train and a drive switching clutch (not shown). The drive switching clutch in this case is exactly the same as the drive switching clutch used to rotationally drive the wiper blade 10 described above.

In FIG. 3, reference numeral 14 denotes a wiper rotation sensor. The wiper rotation sensor 14 detects the sensor flag section 9a and operates the wiper blade 1
This is to detect a rotation phase of 0. As the wiper rotation sensor 14, for example, an optical type (configured by an LED and a phototransistor) is used, and when the phototransistor detects light from the LED in accordance with the rotation position of the sensor flag, A phototransistor configured to generate a signal can be used. The rotation phase of the wiper blade 10 can be detected by the detection signal from the phototransistor. Reference numeral 15 denotes a wiper lifting sensor. The wiper elevation sensor 15 detects the phase of the elevation cam 13 by detecting the wiper elevation flag 16.
The wiper lift flag 16 is fixed to a drive transmission shaft of the lift cam 13, and rotates together with the lift cam 13. As the wiper elevating sensor 15, the same optical detecting means as the wiper rotation sensor 14 can be used. 17 is a blade cleaner. The blade cleaner 17 is formed of an ink absorber fixed (attached) to the wiper case 8. The ink attached to the wiper blade 10 can be removed by rotating the wiper blade 10 and bringing its tip into contact with the blade cleaner 17.

Next, the wiping operation of the wiper unit 302 shown in FIG. 3 will be described. (A), (b) of FIG.
And (c) is a schematic sectional view showing a wiping operation in a vertical section similar to (c) of FIG. In FIG.
Normally, the lifting cam 13 is stopped at the position shown in FIG. 4A, and in this state, the wiper lifting sensor 15 shown in FIG. 3B detects the wiper lifting flag 16. In this state, the wiper unit 302
The wiper blade 10 is pushed down by being rotated counterclockwise around the pivot shaft 6 against the urging force of the urging spring 12 by the lifting cam 13.
Never touch. Therefore, when the CPU issues a wiping process command at an appropriate time during recording or after the suction recovery process, the carriage 200 moves to the home position (the right cap position in FIG. 1). Then, the CPU turns on the wiper elevating drive switching clutch, drives the step motor 1, and drives the elevating cam 13.
Is rotated to the phase shown in FIG. The rotation amount at this time is determined by the wiper up / down sensor 15
The rotation amount is set in advance to a predetermined step after the ON or OFF signal of No. 6 is detected. Then, the contact between the elevating cam 13 and the cam contact portion 8a is released, and the wiper case 8 is rotated clockwise around the swing shaft 6 by the urging force of the urging spring 12 to move upward, and the wiper The case 8 comes into contact with a stopper (not shown) provided on the side plate 40 of the supply / recovery unit 300 to be in the state of FIG. In this state, the carriage 200 is still located at the right home position (cap position) as shown in FIG. 2, and the contact roller 11 supported by the wiper case 8 is positioned on the guide surface 210 of the carriage 200. (Moving path surface).

Then, the carriage 200 moves from the right home position to the left, and the wiper unit 30 moves.
2, the contact roller 11 moves to the carriage 20.
0 on the guide surface 210, and the wiper unit 3
02 is pushed down and rotated counterclockwise in the figure around the swing shaft 6 to be in the state of FIG.
Here, as shown in FIG. 4C, when the contact roller 11 is in contact with the guide surface 210 of the carriage 200,
Since the distance (height difference) H between the upper surface of the contact roller 11 and the tip (upper end) of the wiper blade 10 is always constant in the wiper unit, the amount of penetration of the wiper blade 10 into the discharge port surface 81 of the recording head 201 is set. Is always set to a predetermined appropriate value X. That is, by setting the distance H between the upper ends to a predetermined value in advance, the amount of penetration X of the wiper blade 10 can always be set to an appropriate value. The components related to the blade penetration amount X are the guide surface 210 of the carriage 200 → the contact roller 11 → the wiper case 8 → the blade holder 9 → the wiper blade 10. Can be greatly reduced, and therefore, the blade penetration amount X can be stably secured with high accuracy.

Then, the CPU turns on a drive switching clutch (not shown) for rotating the wiper, and switches the step motor 1, which is the drive source of the supply / recovery unit 300, to the carriage 2.
00 and rotated in synchronization with the movement of the wiper blade 1
0 is brought into contact with the discharge port surface 81 of the recording head 201 to wipe the peripheral edge of the discharge port. FIG. 4C shows the state at the time of this wiping. Further, three wiper blades 10 are provided at equal intervals in the circumferential direction of the blade holder 9, so that three recording heads 201 can be wiped and cleaned (wiping) during one rotation (one rotation). . Six print heads 201 are mounted on the carriage 200 as in this embodiment.
In the case of mounting, all the recording heads 201 can be wiped off by rotating the wiper holder 9 twice (two rotations). Further, the wiper rotating shaft 5 is rotated as described above to wipe the discharge port surface 81, and the rotation causes the wiper blades 10 to abut (slidably contact) the blade cleaner 17, thereby causing the ink adhered to the wiper blades 10 to move. Foreign matter such as can be removed. Thus, the ejection port surface of the recording head 201 can be constantly wiped while the wiper blade 10 is cleaned.

As is clear from the configuration and operation of FIGS. 3 and 4, the center of rotation of the wiper unit 302 for raising and lowering is one for transmitting the rotation of the wiper blade 10.
Since it is the same as the axis of the swing shaft 6, which is one of the support shafts, it is possible to simultaneously raise and lower the wiper blade 10 and transmit the rotational drive of the wiper blade. In other words, since the swinging of the wiper unit 302 for raising and lowering is performed around the support shaft (swinging shaft 6) of the wiper gear (B) 3, the wiper gear (B) 3 and the wiper gear (C) 4 Can be maintained at all times, and both drive transmission for raising and lowering the wiper blade 10 (elevation by swinging) and drive transmission for rotation (rotation for wiping) can be achieved.

When the wiping operation of the recording head 201 is completed, the CPU controls the drive switching clutch for raising and lowering the wiper and the step motor 1 which is the driving source, and rotates the lifting cam 13 so that the guide surface 210 and The contact between the contact roller 11 and the wiper blade 10 and the recording head 201 are released, and the state shown in FIG. In this state, the carriage 200
Becomes free, and a recording operation and various next operations can be executed.

Next, when recording on recording media having different thicknesses, the distance between OHs (paper distance) is adjusted to be constant.
The amount of intrusion of the wiper blade 10 when switching the height of the carriage 200 will be described. FIG. 5 shows the carriage 2
It is a typical partial side view which shows the mode of height change of 00.
In FIG. 5, a carriage 200 is guided and supported (suspended) by a carriage shaft 45 and a stay (guide rail) 50 provided in the apparatus main body, so that a recording medium (recording paper) 101 on a platen 51 and a recording head The distance 201 (the distance between OH and the distance between papers) to the discharge port surface of 201 is maintained at a predetermined value. Since the distance between OHs changes when the paper thickness of the recording medium 101 changes, the carriage 200 is provided with a height switching mechanism to keep the distance between OHs constant. The height switching mechanism includes a carriage roller 2 on the carriage 200.
00a, and the carriage roller 200
The rotation axis of the carriage 200 is adjusted by an unillustrated adjusting means.
By moving in the direction of arrow J in FIG.
The carriage 200 (recording head 201) is configured to swing about the carriage shaft 45 in the direction of arrow K in FIG. 5 to move the ejection port surface up and down, thereby switching the OH distance.

FIGS. 6A, 6B and 6C are operation diagrams showing the operation of the wiper unit 302 when the height of the carriage 200 is switched, in a cross section similar to FIG. Next, the amount of the wiper blade 10 entering the ejection port surface 81 of the recording head 201 will be described with reference to FIG. FIG. 6A shows a state in which the carriage 200 (recording head 201) is raised upward by a distance D from the state of FIG. This shows a state where the distance is adjusted to an appropriate value. When the carriage 200 is raised, the guide surface 210 provided on the carriage is also raised by the distance D.

Therefore, similarly to the operation described with reference to FIG.
, The amount of penetration Y of the wiper blade 10 into the discharge port surface is determined. In this case, since the height difference (distance) H between the upper surface of the contact roller 11 and the tip of the wiper blade 10 is always constant even when the height of the carriage 200 is changed, the height of the guide surface 210 changes. Since the distance from the wiper blade 10 with respect to the guide surface 210 does not change even if this occurs, the penetration amount Y of the wiper blade 10 in FIG. 6C and the penetration amount (appropriate (The amount of intrusion) X, and can be kept constant at all times. Thereby, wiping performance at the time of wiping can be stabilized.

In the above embodiment, a serial recording type ink jet recording apparatus for recording while moving the recording means relative to a recording medium (recording paper or the like) has been described as an example. The same effect can also be applied to a line recording type ink jet recording apparatus that records only by sub-scanning using a line type recording unit having a length covering the entire width or a part of the recording medium. It can be achieved. In addition, the present invention uses a recording apparatus using a single recording unit, or a plurality of recording units that perform recording with the same color and different densities, in addition to a color recording apparatus that uses a plurality of recording units that record with inks of different colors. The present invention can be similarly applied to a gradation recording apparatus and a recording apparatus in which these are combined, and can achieve the same effect.

Further, the present invention provides a configuration using a replaceable ink cartridge in which the recording head and the ink tank are integrated, a configuration in which the recording head and the ink tank are separated, and the space between them is connected by an ink supply tube or the like. The present invention can be similarly applied to any arrangement of the recording head and the ink tank, and the same effect can be obtained. Note that, in the present invention, the ink jet recording apparatus
For example, the present invention can be applied to a case where a recording unit using an electromechanical transducer such as a piezo element is used, and among others, an ink jet recording apparatus using a recording unit of a type that uses thermal energy to eject ink. In which excellent effects are obtained. According to such a method, it is possible to achieve higher density and higher definition of recording.

[0048]

As is apparent from the above description, according to the first aspect of the present invention, recording is performed by discharging ink from the recording means to the recording medium, and the plurality of wiper blades are rotated in the moving direction of the recording means. In the ink jet recording apparatus for wiping the discharge port surface of the recording means, a rotating means for rotating a wiper blade, an elevating means for elevating and lowering the wiper unit, a contact member contacting a guide surface of a carriage, A biasing means for biasing the contact member against the guide surface, wherein the swing center of the wiper unit is made common to the axis of one rotation shaft of the rotating means. The amount of intrusion of the wiper blade into the wiper blade can be stably and accurately maintained at an appropriate value. Can be secured to a fixed, adhered ink discharge port surface of the recording head can be realized reliably removed may wiping operation of an ink jet recording apparatus is provided which can eliminate the deterioration of the image quality due to discharge failure. According to the second aspect of the present invention, in addition to the configuration of the first aspect, the rotating means and the lifting / lowering means are configured to be driven by switching the drive of the same drive source. Can be achieved.

[Brief description of the drawings]

FIG. 1 is a perspective view, partially cut away, showing an embodiment of an ink jet recording apparatus to which the present invention is applied.

FIGS. 2A and 2B are a plan view and a front view, respectively, showing a state in which a carriage has moved to a supply / recovery unit in an embodiment of the ink jet recording apparatus to which the present invention is applied.

3 is a plan view (a), a front view (b), and a longitudinal sectional view (c) of the wiper unit in FIG.

FIG. 4 is a longitudinal sectional view showing an operation at the time of wiping of the wiper unit of FIG. 3;

FIG. 5 is a partial side view showing how the height of the carriage is switched.

FIG. 6 is an operation diagram showing an operation of the wiper unit when switching the height of the carriage.

FIG. 7 is a partial perspective view schematically illustrating the structure of an ink ejection unit of the recording unit.

FIG. 8 is an external perspective view of the inkjet recording apparatus.

FIG. 9 is a perspective view showing a state where an upper cover of the ink jet recording apparatus of FIG. 8 is removed.

FIG. 10 is an ink flow path diagram of the ink jet recording apparatus.

FIG. 11 is a plan view (a) and a front view (b) of a supply / recovery unit in the ink jet recording apparatus.

12 is a plan view (a) and a front view (b) of a conventional wiper unit provided in the supply / recovery unit of FIG.

FIG. 13 is a front view illustrating an operation of wiping an ejection port of a recording unit by the wiper unit of FIG. 12;

FIG. 14 is a schematic diagram illustrating a state of a wiper blade when a discharge port surface of a recording unit is being wiped.

FIG. 15 is a schematic perspective view showing a configuration of a carriage height switching mechanism.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Step motor 2 Wiper gear (A) 3 Wiper gear (B) 4 Wiper gear (C) 5 Wiper rotation shaft 6 Swing shaft 7 Wiper bearing 8 Wiper case 8a Cam contact part 9 Blade holder 9a Sensor flag 10 Wiper blade 11 Abutment roller 12 urging spring 13 elevating cam 14 wiper rotation sensor 15 wiper elevating sensor 16 wiper elevating flag 17 blade cleaner 40 side plate 45 carriage shaft 50 stay (guide rail) 51 platen 81 discharge port surface 82 discharge port 85 electrothermal converter REFERENCE SIGNS LIST 100 inkjet recording apparatus 101 recording medium (recording paper) 110 transport roller 130 ink tank 190 apparatus main body 200 carriage 200 a carriage roller 201 recording means (recording head) 210 guide surface 300 supply / turn Unit 302 wiper unit (wiping mechanism) 501 sub tank 508 cap 504a suction recovery tube pump 504b feeding tube pump

Claims (4)

[Claims] 1. An ink jet recording apparatus which performs recording by discharging ink from a recording unit to a recording medium, and wipes an ejection opening surface of the recording unit by rotating a plurality of wiper blades in a moving direction of the recording unit. Rotating means for rotating the blade, elevating means for elevating and lowering the wiper unit by swinging, an abutting member abutting on a guide surface of the carriage, and urging means for urging the abutting member against the guide surface, An ink jet recording apparatus, wherein a swing center of the wiper unit is common to an axis of one rotation shaft of the rotation unit. 2. An ink jet recording apparatus according to claim 1, wherein said rotating means and said elevating means are driven by drive switching of the same driving source. 3. The ink-jet recording apparatus according to claim 1, wherein said recording means is an ink-jet recording means provided with an electrothermal converter for generating thermal energy used for discharging ink. Recording device. 4. An ink jet recording apparatus according to claim 3, wherein said recording means discharges the ink from a discharge port using film boiling generated in the ink by thermal energy generated by the electrothermal transducer. .