JP4681714B2 - Inkjet recording device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention Recording is performed by discharging ink from the recording means to the recording material. The present invention relates to an ink jet recording apparatus.
[0002]
[Prior art]
Conventionally, as a recording apparatus (printing apparatus, etc.) that performs recording (printing, printing, etc.) on a recording material (recording medium, print medium, also simply referred to as recording paper) such as paper, cloth, plastic sheet, OHP sheet, etc. Various recording methods, for example, recording using recording means (recording head, print head) by a wire dot method, a thermal method, a thermal transfer method, or an inkjet method have been proposed.
[0003]
Among such recording apparatuses, an inkjet recording type recording apparatus (hereinafter also referred to as an inkjet apparatus) that performs recording on a recording material (recording paper) by ejecting ink from an ejection port is a low-noise non-impact. This is a recording method of a mold and can perform a high-density and high-speed recording operation. In general, a serial type ink jet recording apparatus widely used is a carriage driving unit that drives a carriage on which a recording head (recording unit) is mounted, and a conveyance that conveys (paper feeds) a recording material (recording paper) through a recording unit. Mechanism drive means and drive system control means for controlling them are provided.
[0004]
On the other hand, as an energy generating element that generates energy used to eject ink from the ejection port of the recording head (recording means), an element that uses an electromechanical transducer such as a piezo element, or an electromagnetic wave such as a laser is irradiated. There are those that generate heat and discharge ink droplets by the action of this heat generation, and those that heat a liquid by an electrothermal transducer element having a heating resistor. Among them, an ink jet recording type recording head that uses thermal energy to discharge ink as droplets can perform high-resolution recording because the discharge ports can be arranged at high density. Among them, a recording head using an electrothermal transducer element as an energy generating element can be easily downsized, and has the advantages of IC technology and microfabrication technology that have made remarkable progress in technology and reliability in recent semiconductor fields. This is advantageous because it can be fully utilized in manufacturing, can be easily mounted at high density, and the manufacturing cost is low.
[0005]
As described above, the ink jet recording method is a very excellent recording method having a simple configuration, but there is a technical problem to be solved on one side. One of the technical problems of ink jet recording apparatuses is clogging of the discharge port. Generally, as a means for eliminating this clogging, pump means are used to suck and discharge ink from the discharge port of the recording head. Recovery processing means (recovery unit) that maintains and recovers the ink discharge performance of the discharge ports by discharging the pressure is used. Specifically, in the recovery means for sucking and discharging ink, the ink is sucked by the suction pump from the ejection port (nozzle tip), thereby being present in the recording head and the flow path for supplying ink to the recording system. Viscosity ink (thickening ink), fine dust, bubbles in the ink liquid, and the like are sucked and discharged from the discharge port together with the ink. In order to execute such a suction recovery operation, it is necessary to perform an opening / closing operation of the suction cap and an on / off operation of the suction pump.
[0006]
As a means for this, first, the suction cap is opened and closed using a carriage driving means mounted with a recording head, that is, the carriage is moved to the suction cap opening / closing position, thereby being provided on the cap means. There is a configuration in which a boss or the like is engaged with a carriage and a cap is brought into contact with a discharge port surface of a recording head to cap the discharge port. In addition, for inkjet recording devices that have multiple suction recovery modes or are equipped with a suction selection shared air communication valve, etc., as a means to communicate the atmosphere inside the cap with the air while capping the recording head, drive the carriage in the same way This is achieved by moving the carriage to the atmosphere communication position where the inside of the cap is communicated with the atmosphere using the means for making it. The operation of the suction pump corresponds to a suction recovery operation or the like by temporarily using a drive source for conveying a recording material (recording paper). The configuration of the recovery means (recovery unit) as described above is generally well known, and is widely used in recovery devices of conventional ink jet recording apparatuses.
[0007]
[Problems to be solved by the invention]
However, the ink jet recording apparatus having the suction cap contact / separation position and the air communication valve opening / closing position as described above, the width of the mounting body in the carriage movement direction increases depending on the number of these positions, and the mounting The body size will increase. In addition, when a driving force is transmitted from a drive source for recording material conveyance (for recording paper conveyance) to a suction pump as a suction means, a drive transmission switching mechanism is required to switch driving between recording paper conveyance and suction recovery. Therefore, the size of the main body of the device is further increased by the space of the drive transmission switching mechanism, and a plurality of suction operation modes must be controlled, so that the drive transmission switching mechanism itself becomes complicated and the cost increases due to an increase in the number of parts. I will invite you. Therefore, it is an important technical problem to be solved to provide a recovery unit for an ink jet recording apparatus that can arbitrarily perform a plurality of recovery operations by forward and reverse rotation of one drive source.
[0008]
The present invention has been made in view of such technical problems, and the present invention provides a recovery device (recovery unit) for maintenance of the recording means of an ink jet recording apparatus using a single drive source in the recovery apparatus. The drive operation is controlled and stable maintenance operation can be performed without depending on the drive transmission switching mechanism from other drive sources. Ru An ink jet recording apparatus is to be provided.
In addition, the present invention can be easily mounted on a space-saving ink jet recording apparatus by realizing a recovery-unit-completed unit that does not have a transmission switching mechanism from another drive source in performing a recovery operation ( It is to provide a recovery unit.
[0009]
That is, the object of the present invention can be performed by selecting a plurality of suction recovery modes by one drive source in the recovery unit without depending on the driving force from other drive sources, and the completion of suction recovery. By eliminating the need for conventional processing operations such as applying positive pressure due to reverse rotation of the suction means until the cap is sufficiently retracted from the discharge port surface later, the cap is in contact with the discharge port surface during the suction recovery operation. The operation to move can be eliminated Ru And an inkjet recording apparatus.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a cap for capping the ejection port surface of a recording head that performs recording by discharging ink, a suction tube communicating with the cap, and pressing the suction tube to perform the suction. A roller for generating a negative pressure in the tube, a roller holder for rotatably supporting the roller, an atmospheric communication valve for switching the inside of the cap to an atmospheric communication state or a sealed state, a motor capable of forward and reverse rotation, When the motor rotates in the forward direction, the roller holder rotates in the first direction so that the roller is pressed against the tube and the tube is rubbed. When the motor rotates in the reverse direction, the roller holder moves in the first direction. An inkjet recording apparatus in which the pressing of the roller against the tube is released by rotating in a second direction opposite to When the rotation direction of the motor is switched from normal rotation to reverse rotation, before the drive of the motor is transmitted to the roller holder, the atmospheric communication valve is driven and the inside of the cap is changed from the atmospheric communication state to the sealed state. It is characterized by switching.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be specifically described below with reference to the drawings. Throughout the drawings, the same reference numerals indicate the same or corresponding parts. FIG. 1 is a schematic perspective view showing a schematic configuration of an ink jet recording apparatus provided with an embodiment of a recovery unit to which the present invention is applied, and FIG. 2 is a recovery unit of the ink jet recording apparatus in FIG. FIG. 3 is a schematic perspective view showing an embodiment of the recovery unit as viewed obliquely from above, and FIG. 3 is a schematic exploded perspective view showing the internal structure of the recovery unit in FIG.
[0013]
1 to 3, an inkjet recording apparatus 1 includes drive motors M1 and M2 that are drive sources, a carriage 2 on which a recording head (inkjet recording head) 3 as a recording unit is mounted, and a carriage 2 that is driven by the drive motor M1. A transmission mechanism 4 that reciprocates in the direction of a double arrow A, a paper feed mechanism 5 that feeds and transports recording paper P as a recording material (recording medium) (feed and transport of recording paper), and a recording head 3 And a recovery unit (recovery device) 10 for performing the discharge recovery process (maintenance and maintenance of ink discharge performance, maintenance). In such an ink jet recording apparatus 1, the recording paper P is fed by the paper feeding mechanism 5, and predetermined recording is performed on the recording paper P by the recording head 3. An ink cartridge 6 for supplying ink to the recording head 3 is detachably held (mounted) on the carriage 2 which is a member on which the recording head 3 is mounted.
[0014]
Ink stored in the ink cartridge 6 is supplied to the recording head 3. In this case, the carriage 2 and the recording head 3 can achieve and maintain a required electrical connection by properly contacting the joint surfaces of both members. The recording head 3 is an ink jet recording head that selectively discharges ink from a plurality of discharge ports by applying energy according to a recording signal. The recording head 3 is an ink jet recording unit that discharges ink using thermal energy, and includes an electrothermal converter for generating thermal energy. Further, the recording head 3 performs recording by ejecting ink from the ejection port by utilizing pressure change caused by bubble growth and contraction caused by film boiling caused by thermal energy applied by the electrothermal transducer. It is. The electrothermal converter is provided corresponding to each of the discharge ports, and discharges ink from the corresponding discharge port by applying a pulse voltage to the corresponding electrothermal converter in accordance with a recording signal.
[0015]
FIG. 19 is a partial perspective view schematically showing the structure of the ink ejection section (one ejection port array) of the recording means (recording head) 3. In FIG. 19, a plurality of discharge ports are provided at a predetermined pitch on a discharge port surface 23 facing a recording material P such as recording paper with a predetermined gap (for example, about 0.3 to 2.0 mm). 49 is formed, and an electrothermal conversion body (such as a heating resistor) 52 for generating energy for ink discharge is arranged along the wall surface of each liquid passage 51 communicating with the common liquid chamber 50 and each discharge port 49. It is installed. The recording head 3 is guided and supported in such a positional relationship that the discharge ports 49 are aligned in a direction crossing the main scanning movement direction (in this embodiment mounted on the carriage 2, the movement direction of the carriage 2 and the direction of the double arrow A). Has been. In this way, the corresponding electrothermal transducer 52 is driven (applied with a pulse voltage) based on the image signal or the ejection signal to cause the ink in the liquid path 51 to boil, and the ink generated from the ejection port 49 by the pressure generated at that time. A recording means (recording head) 3 for discharging the ink is configured.
[0016]
In FIG. 1, a carriage 2 is connected to a part of a drive belt 7 of a transmission mechanism 4 that transmits a drive force of a drive motor M1, and is slidably guided along a guide shaft 13 in the direction of a double arrow A. It is mounted so as to be driven (reciprocating drive) by the drive motor M1. Accordingly, the carriage 2 reciprocates along the guide shaft 13 by forward and reverse rotation of the drive motor M1. The apparatus body is provided with a scale 8 indicating the absolute position of the carriage 2 in the direction of arrow A. In this embodiment, the scale 8 uses a transparent PET film printed with black bars at a necessary pitch, one of which is fixed to the chassis 9 and the other is a leaf spring (not shown). It is supported.
[0017]
In the illustrated ink jet recording apparatus 1, a platen (not shown) is provided facing the discharge port surface 23 in which the discharge port 49 of the recording head 3 is formed, and the recording head 3 is mounted by the driving force of the driving motor M <b> 1. At the same time as the carriage 2 is reciprocated, a recording signal is given to the recording head 3 to eject ink, whereby recording is performed over the entire width of the recording paper P as a recording material conveyed on the platen. Reference numeral 14 denotes a conveyance roller driven by a conveyance motor M2 to convey the recording paper (recording sheet) P. Reference numeral 15 denotes a pinch roller for bringing the recording paper P into contact with the conveyance roller 14 by a spring (not shown). Is a pinch roller holder that rotatably supports the pinch roller 15.
[0018]
Reference numeral 17 denotes a transport roller gear fixed to one end of the transport roller 14, and the transport roller 14 is driven by the rotation of the transport motor M2 transmitted to the transport roller gear 17 via the intermediate gear 18. Yes. Reference numeral 19 denotes a discharge roller gear fixed to a discharge roller (not shown) for discharging a recording sheet on which an image is formed by the recording head 3 to the outside of the recording apparatus. The discharge roller includes an intermediate gear 18 on the discharge roller gear 19. It is driven by the rotation of the transport motor M2 transmitted through the motor. Reference numeral 21 denotes a spur roller that presses the recording sheet P against the discharge roller by a spring (not shown), and 22 denotes a spur holder that rotatably supports the spur roller 21.
[0019]
Further, in the ink jet recording apparatus 1, the recording head 3 is located at a desired position (for example, a position corresponding to the home position) outside the range of reciprocal motion for recording operation of the carriage 2 on which the recording head 3 is mounted (outside the recording area). A recovery unit (recovery device) 10 is provided for maintaining the ink discharge performance and recovering the discharge failure when it occurs. The recovery unit 10 is provided with a capping unit 11 for capping the ejection port surface 23 of the recording head 3 and a wiping unit 12 for cleaning (wiping and cleaning) the ejection port surface 23 of the recording head 3. Then, in a state where the discharge port surface 23 is capped by the capping unit 11 and the discharge port 49 is sealed, the suction unit (suction pump or the like) connected to the capping unit 11 is driven, whereby the ink is discharged from the discharge port 49. A suction recovery process for forcibly sucking and discharging the is performed. The suction means (suction pump or the like) is also provided in the recovery unit 10.
[0020]
By such suction recovery processing, the thickened ink, bubbles, and the like in the ink flow path of the recording head 3 are discharged and removed from the discharge ports 49, thereby maintaining and recovering the ink discharge performance of the recording head 3. Further, by capping the ejection port surface 23 of the recording head 3 during non-recording or the like, the recording head can be protected and ink can be prevented from drying. Further, the wiping means 12 is for wiping off ink droplets, paper dust and the like adhering to the discharge port surface 23 of the recording head 3, and is disposed in the vicinity of the capping means 11. The capping unit 11, the wiping unit 12, and the suction unit can maintain the ink ejection performance of the recording head 3 in a normal state.
[0021]
FIG. 4 is a schematic side view showing a gear train as a transmission mechanism provided in the recovery unit 10. 2, 3, and 4, the recovery unit 10 includes a suction unit 48, a capping unit 11, a wiping unit 12, and the like as a recovery unit for non-ejection or ejection failure of the recording head 3. The suction means 48 is constituted by a tube pump. The tube pump (suction means) 48 has two suction tubes 32 arranged so that the arc surface of the recovery base 20 has an inner surface as a guide surface along the arc surface, and these suction tubes 32 are pressed against each other. There are provided a predetermined number (four in total in this embodiment) of pressure rollers 33 that generate negative pressure in the suction tube 32 by rolling while squeezing the suction tube.
[0022]
The pressure roller 33 is disposed so as to squeeze the suction tube 32 by rolling along the suction tube 32 while being pressed against the suction tube 32 by a pressure spring (not shown). The pressure roller 33 is urged toward the side pressing the suction tube 32 during the suction operation, and has a long hole shape formed in the pressure roller holder 31 so that it can be retracted from the suction tube 32 except during the suction operation. The shaft is supported so as to be movable along the groove. In the present embodiment, two such pressure rollers 31 are arranged for one suction tube 32.
[0023]
In the present embodiment, the arc surface of the recovery base 20 that guides the suction tube 32 is formed in a substantially semicircular shape with a central angle of about 180 degrees, and the pressure roller 33 on the pressure roller holder 31 that is rotationally driven is 180 degrees. Since the two pressure rollers are arranged so as to face each other, when the one pressure roller is separated from the state of pressing the suction tube 32, the other pressure roller 33 may start pressing the suction tube 32. Therefore, by continuously rotating the two pressure rollers 33, the suction operation can be continuously performed while maintaining the negative pressure in the suction tube 32. In addition, when the guide surface of the suction tube 32 is substantially circular (360 degrees), the suction operation can be continuously performed with a single pressure roller. Furthermore, three or more pressure rollers may be provided to perform a continuous suction operation.
[0024]
The pressure roller holder 31 that pivotally supports the pressure roller 33 is pivotally supported by the pressure roller holder guide 30 so as to be rotatable in the radial direction of the arc guide surface of the recovery base 20. It works to push and retract. The pressure roller holder guide 30 has shafts at both ends and is pivotally supported at the arc center of a semicircular arc guide surface on which the suction tube 32 of the recovery base 20 is provided, and from a drive motor (hereinafter referred to as PG motor) M3. It is arranged to be able to rotate by transmitting the drive.
[0025]
Here, the transmission of the driving force from the PG motor M3 to the suction means 48 is first transmitted to the PG gear 24 and the pump gear 27, and then the pump gear 27 supported by the rotary shaft of the pressure roller holder guide 30 is transmitted. Is transmitted to the pump gear trigger boss 41 disposed on one end surface of the pressure roller holder guide 30, and the pump gear trigger boss 41 is brought into contact with the pump gear trigger ribs 42 a and 42 b by the rotation of the pump gear 27. This is performed by a transmission path that is transmitted to the suction means 48. That is, the driving force from the PG motor M3 is transmitted to the suction means 48 through the PG gear 24 and the pump gear 27, and the pump gear 27 is pivotally supported on the rotating shaft of the pressure roller holder guide 30, and the pressure roller holder guide 30 is further supported. This is transmitted when the pump gear trigger boss 41 disposed on one end surface of the pump abuts against the pump gear trigger ribs 42 a and 42 b by the rotation of the pump gear 27.
[0026]
Here, the shape of the pump gear 27 will be described. The pump gear 27 includes two ribs (pump gear trigger ribs 42a and 42b) inside, a space is provided on the side surface, and a boss (pump trigger boss entering the space). 41) and the ribs are in contact with each other so that the driving force is transmitted to the suction means 48 side. The suction means 48 is directly connected to the rotational drive of the PG motor M3. The suction means 48 performs a suction operation by one-way rotation (hereinafter referred to as forward rotation) and a reverse rotation (hereinafter referred to as reverse rotation). The pressure roller 33 is configured to move in the releasing direction from the pressed state of the suction tube 32.
[0027]
FIG. 5 is a sectional view showing a state immediately after the drive transmission by the pump gear to the tube pump as the suction means in one embodiment of the recovery unit to which the present invention is applied, and FIG. 6 is a pump gear for the tube pump of FIG. FIG. 6 is a cross-sectional view showing a state immediately before the drive by is transmitted, and FIG. 6 is a cross-sectional view showing a state in which the drive by the pump gear is transmitted to the tube pump of FIG.
FIG. 8 is a cross-sectional view showing a state immediately after the pressure roller of the tube pump as the suction means in the embodiment of the recovery unit to which the present invention is applied is pressing the tube and the drive transmission by the pump gear is released. 9 is a sectional view showing a state immediately before the drive by the pump gear is transmitted to the tube pump of FIG. 8, and FIG. 10 is the state where the drive by the pump gear to the tube pump of FIG. 9 is transmitted and the pressure roller is released. FIG.
[0028]
FIG. 11 is a schematic perspective view showing a state in which both the Bk atmospheric communication valve and the Color atmospheric communication valve of the capping means in the embodiment of the recovery unit to which the present invention is applied are closed (cap closed state); 12 is a schematic perspective view showing a state in which both the Bk atmospheric communication valve and the color atmospheric communication valve for the capping means in the recovery unit of FIG. 11 are open (empty suction, colloidal removal state). FIG. 14 is a schematic perspective view showing a state in which the Color atmosphere communication valve of the capping means in the recovery unit of FIG. 11 is opened and the Bk atmosphere communication valve is closed (Bk suction state); FIG. 11 shows that the color communication valve for color is closed and the atmospheric communication valve for Bk among the atmospheric communication valves of the capping means in the recovery unit of FIG. It is a schematic perspective view showing the opened and has state (Color suction state).
15 is a cross-sectional view showing a state where the pressure roller of the tube pump as the suction means in the embodiment of the recovery unit to which the present invention is applied is in the released state and the drive transmission by the pump gear is released. FIG. 16 is a cross-sectional view showing a state in which the tube pump in FIG. 15 receives drive transmission by the pump gear and presses the pressure roller of the suction means against the tube.
[0029]
Further, FIG. 17 is a chart showing each state during the suction mode selection operation of the cap of the capping means and the atmospheric communication valve in one embodiment of the recovery unit to which the present invention is applied, and FIG. 18 is a recovery unit to which the present invention is applied. It is a flowchart which shows the sequence of the general suction recovery operation | movement in one Example. Hereinafter, with reference to FIGS. 5 to 18, the characteristic configuration of the recovery unit for an ink jet recording apparatus to which the present invention is applied and the function and effect thereof will be described more specifically.
[0030]
The capping unit 11 includes a cap 35 that contacts the discharge port surface of the recording head 3, a cap absorber 44 for efficiently sucking ink discharged from the discharge port surface of the recording head 3 shown in FIG. A cap holder 36 that can press the cap 35 against the discharge port surface 23 of the recording head 3 by a cap spring (not shown), and a cap spring that applies a cap pressure to the cap holder 36 by a cap spring (not shown). A cap base 34 that slidably supports 36 in the vertical direction, a capping means elevating lever 37 that functions as an arm member for bringing the cap 35 into and out of contact with the discharge port surface 23 of the recording head 3, and the inside of the cap 35. Air communication valves 46a and 46b for making them sealed or open (see FIGS. 11 to 14) , And is made of. As shown in FIGS. 11 to 14, the atmosphere communication valves 46 a and 46 b open and close the atmosphere communication tube 45 that connects the cap 35 and the atmosphere communication hole 47 provided in the cap base 34, thereby opening the inside of the cap 35. The cap 35 is opened to the atmosphere or a sealed state is created inside the cap 35.
[0031]
A suction tube 32 constituting a tube pump as the suction means 48 is connected to the capping means 11 via a joint portion of the cap holder 36, whereby the cap 35 contacts the discharge port surface 23 of the recording head 3. While in contact, the suction operation of the suction means 48 can apply a negative pressure in the cap 35 to suck and discharge ink from the recording head 3. In this embodiment, since the Bk ink and the Color ink are sucked by the separate suction tubes 32, two cap 35 closed spaces, two cap absorbers 44 in accordance with the closed space, and an atmosphere communication tube are provided. Two air release valves 46a and 46b are arranged respectively. The raising / lowering operation for bringing the capping unit 11 into contact with the recording head 3 and the opening / closing operation of the air release valves 46a, 46b are performed by transmitting the driving force from the PG motor M3 via the PG gears 25, 26 and the like. Done.
[0032]
The raising / lowering operation for bringing the capping unit 11 into contact with the recording head 3 and the opening / closing operation of the atmosphere release valves 46a, 46b are cams 38 that perform the raising / lowering operation of the capping unit 11 and the opening / closing operation of the atmosphere communication valves 46a, 46b. The one-way drive transmission means (one-way clutch gear) 28 that transmits the driving force from the PG motor M3 to the cam 38 when rotating in one direction and does not transmit the drive to the cam 38 by idling when rotating in the other direction. It is performed by the structure which transmits and receives a driving force.
[0033]
The cam 38 is used for controlling the driving of the wiping means 12 and the raising / lowering operation of the CR lock lever 29 in addition to the operation of the capping means 11 described above. The CR lock lever 29 is provided as a positioning between the recording head 3 and the capping means 11 constituting the recovery unit in this embodiment during the recovery operation of the recording head 3, and also controls the lifting operation. This is done using the cam 38. The operation of each means such as the capping means 11 and the wiping means 12 described above is performed by rotationally positioning the cam 38 with the cam position detection sensor flag provided on the cam 38 and the cam position detection sensor 40 to control each means. Is executed.
[0034]
Here, in one embodiment of the recovery unit for an ink jet recording apparatus to which the present invention is applied, the suction means for performing suction recovery is driven by driving the motor in one direction, and the cap is ejected from the recording means by driving in the reverse direction. Both the driving of the capping means 11 for contacting and separating from the surface, or the driving of the capping means 11 and the driving of the wiping means 12 for wiping the discharge port surface 23, the flag portion for position detection on the same axis. It is configured to be driven by a cam and a cam phase detection means, and in addition to this, a characteristic configuration as described below is included.
[0035]
First, the suction recovery mode of the recovery unit for an inkjet recording apparatus to which the present invention is applied will be described with reference to FIGS. When the suction recovery operation of the recording head 3 is performed according to an embodiment of the recovery unit 10 to which the present invention is applied, the suction recovery is performed by a sequence as shown in the flowchart of FIG. The flow shown in FIG. 18 shows a general suction recovery operation of the recovery unit in this embodiment. Details of the suction recovery mode in this embodiment will be described below with reference to the flow of FIG.
[0036]
In FIG. 18, when a suction recovery operation command is issued, the position of the cam 38 constituting the recovery unit 10 is detected by the cam phase detection sensor 40, and the positions of the capping means 11, the wiping means 12, and the like are confirmed. When the recording head 3 is not in the suction recovery operation position, the cam position detection sensor 40 confirms that the recording head 3 and the capping means 11 and wiping means 12 constituting the recovery unit 10 do not interfere with each other. After confirmation, the transmission mechanism 4 shown in FIG. 1 is driven to move the recording head 3 to the suction recovery operation position. Thereafter, the cam 38 is driven by the driving of the PG motor M3, and the capping means 11 is brought into contact with the discharge port surface 23 of the recording head 3 by the rotation of the cam 38 in order to execute the suction recovery operation.
[0037]
Since the rotation direction of the PG motor M3 at that time is the rotation direction R shown in FIGS. 8 to 10, the pressure roller 33 of the suction means 48 is disposed at a position away from the suction tube 32 as shown in FIG. The inside of the cap 35 communicates with the atmosphere, and even if the suction means 48 rotates, the ink remaining in the suction tube 32 flows back into the cap 35 or a positive pressure is applied to the cap 35 to apply the positive pressure to the recording head 3. The discharge port is configured not to be damaged (inconvenience in ink discharge).
[0038]
After the cap 35 is brought into contact with the discharge port surface 23 of the recording head 3, as a preparation for entering the suction recovery operation, the pressurizing roller 33 constituting the suction means 48 is once pressed against the suction tube 32 by the PG motor M3. The suction means 48 is driven in the direction of rotation in the rotation direction L side. At this time, since the capping unit 11 is in contact with the ejection port surface of the recording head 3, the cap 35 is prevented from applying an excessive negative pressure into the cap 35 when the suction unit 48 rotates in the rotation direction R side. Is brought into contact with the recording head 3, the air release valves 46 a and 46 b are opened by the rotation of the cam 38. When the PG motor M3 is driven, the pump gear 27 receives the rotational force in the L direction from the state shown in FIG. 5 and rotates to the state shown in FIG.
[0039]
Further, the pump gear trigger boss 41 disposed on the end surface on the side where the pump gear 27 is pivotally supported by the shaft of the pressure roller holder guide 30 constituting the suction means 48 by continuing the rotation is provided inside the pump gear 27. A state in which the pumping gear trigger rib 42b comes into contact with the suction means 48 to transmit the rotational force, the suction means 48 is rotated in the rotational direction L as shown in FIG. 7, and the pressure roller 33 is pressed against the suction tube 32. (FIGS. 15 and 16). In this operation, when a suction recovery operation command is input, the suction tube 32 is pressed against the suction tube 32 in order to enable a stable suction recovery operation regardless of the position of the pressure roller 33. By doing so, the pressure roller 33 serves to suppress variations in the amount of crushing of the suction tube 32 in the insensitive area until the pressure roller 33 presses the suction tube 32, that is, variation in the ink suction amount. By performing the above-described operation, even if there is no pressure roller sensor necessary for detecting the position of the pressure roller 33, variations in the ink suction amount can be reduced and a stable suction recovery operation can be performed.
[0040]
Next, after the pressing roller 33 is pressed against the suction tube 32, the suction mode is selected in the recovery unit of this embodiment. The suction mode is selected by opening and closing the atmospheric communication valves 46a and 46b of the capping unit 11 while the cap 35 is in contact with the recording head 3, thereby bringing the inside of the cap 35 into a sealed state or an atmospheric communication state. This is performed by applying a negative pressure to the inside of the cap 35 which is a sealed space by the suction recovery operation, and controlling the cap on the side where ink is discharged from the recording head 3.
[0041]
As shown in FIGS. 11 to 14, the air communication hole 47 is opened and closed according to the positions of the air communication valves 46a and 46b, thereby controlling the opening and closing of the cap 35. FIG. 11 shows the position in the capping state that protects the ejection port surface of the recording head 3, and FIG. 12 shows that the inside of the cap 35 is connected to the atmosphere and the ink in the cap 35 is discharged when preparing for the suction recovery operation. FIG. 13 shows the position of the valve in the Bk ink suction state of the recovery unit 10 in this embodiment, and FIG. 14 similarly shows the position of the valve in the Color ink suction state. Show.
[0042]
Since the operation of the above-described atmospheric communication valve is also performed by one drive source of the PG motor M3 provided in the recovery unit in this embodiment, the atmospheric communication is performed without destroying the state of the pressure roller 33 prepared as a preparation for the suction recovery operation. You must select the valve and select the suction mode. Therefore, as shown in FIG. 17, while the capping means 11 is in contact with the recording head 3, the one-way drive transmission means (one-way clutch gear) 28 is transmitted by the drive of the PG motor M3 to rotate the cam 38 and the atmospheric communication valve. When operating 46 a and 46 b, the pump gear trigger ribs 42 a and 42 b provided on the pump gear 27 come into contact with the pump gear trigger boss 41 provided on the end face of the pressure roller holder guide 30 constituting the suction means 48 and suck. The driving force of the PG motor M3 is not transmitted to the means 48 side. That is, the transmission to the suction means 48 is canceled when the suction mode is selected (shaded area in FIG. 17) while the drive is transmitted to the cam 38 by the PG motor M3.
[0043]
Therefore, the distance between the pump gear trigger ribs 42a and 42b provided in the pump gear 27 is transmitted to the cam 38 in the suction mode selection region, the rotation angle of the cam 38, the gear reduction ratio transmitted from the PG motor M3 to the suction means 48, and the cam 38. In consideration of the gear reduction ratio, an interval in which the driving force of the PG motor M3 is not transmitted to the suction means 48 in the shaded area shown in FIG. In this embodiment, two ribs of the pump gear 27 are required for the number of suction selection modes, but the pump gear provided in the pump gear 27 depends on the number of suction selection modes, the gear reduction ratio, and the rotation amount of the cam 38. The number of trigger ribs may be one. In addition, in the explanatory diagram of the present embodiment, the space formed in the pump gear 27 is defined as a space penetrating, but the space by the trigger rib is configured in a shape in which one side of the pump gear 27 is closed, that is, a gear hollow shape. Also good.
[0044]
After the suction mode is selected, the suction recovery operation for sucking a predetermined amount of ink is performed by rotating the motor in a direction to apply a driving force to the suction means 48 so that the suction recovery operation is performed by driving the PG motor M3. Thereafter, the atmospheric communication valves 46a and 46b are opened by the rotation of the cam 38, as shown in FIG. 12, in order to discharge the sucked discharged ink stored in the cap 35 from the cap 35. If the driving force is transmitted to the suction means 48 during the opening operation of the atmospheric communication valve, the pressure roller 33 rotates in the direction in which the ink flows back through the suction tube 32 into the cap 35, and recording is performed by the ink backflow. Although the head 3 is damaged, the pump gear 27 on the side where the pump gear trigger ribs 42 a and 42 b are separated from the contact with the pump gear trigger boss 41 on the pressure roller holder guide 30 even during the aforementioned operation. Therefore, the suction unit 48 does not rotate and does not cause a problem due to ink backflow.
[0045]
After the atmospheric communication valves 46a and 46b are brought into the communication state, the suction means 48 is transmitted from the PG motor M3 in the direction of the suction recovery operation, and performs an empty suction operation for discharging the ink in the cap 35 to the outside of the recovery unit. Then, the general suction recovery operation ends. In the present embodiment, the above-described general suction recovery operation is the basic control of the Bk ink single suction mode, the Color ink single suction mode, and the Bk, Color ink continuous suction mode, and this suction recovery operation is combined. It corresponds to various suction modes.
[0046]
According to the above-described recovery unit for an ink jet recording apparatus, the capping is performed by driving the suction unit that performs suction recovery by driving the motor in one direction, and contacting and separating the cap from the discharge port surface of the recording unit by driving in the reverse direction. Both the capping means and the wiping means for wiping the discharge port surface can be driven by a cam having a position detecting flag portion on the same axis and a cam phase detecting means. An in-unit recovery unit can be provided for recovery operations related to maintenance.
[0047]
That is, according to the embodiment described above, in the ink jet recording apparatus that performs recording by discharging ink from the recording unit to the recording material, the suction unit that performs ink discharge suction recovery by driving in one direction of one drive source. And a capping means for abutting and separating the cap on the discharge port surface of the recording means by driving in the reverse direction of the one drive source, and the cap abutting on the discharge port surface of the recording means In addition, there is provided a recovery unit for an ink jet recording apparatus, which basically has a configuration in which both the opening and closing means of the communication valve for sealing the space inside the cap or communicating with the atmosphere are driven by one cam. Then, there is provided a recovery unit for an ink jet recording apparatus having a characteristic configuration and operational effects as described below.
[0048]
First, in the basic configuration, the cap is in contact with the discharge port surface of the recording means, and the suction force is transmitted from the drive source to the suction means while the communication valve performs a predetermined opening / closing operation. First, the suction unit is stopped at a certain position for a certain period of time, and a plurality of suction recovery modes can be selected during that time, and a plurality of ribs are provided on the side surface of one gear connected to the suction unit from the driving source. And a transmission means for transmitting a driving force to the suction means after the gear has rotated by a predetermined angle, and the suction means is driven in one direction by the drive source. During the ink discharge suction recovery operation, the driving force is released from the driving source to the cam that drives the capping unit and the open / close unit of the communication valve, and the cap is driven by driving the driving source in the reverse direction. Configuration with one-way drive transmitting means for transmitting a driving force to the cam for driving the opening and closing means keeping means and the communication valve is employed.
[0049]
By adopting such a configuration, multiple suction without applying positive pressure due to reverse rotation of the tube pump in the cap during capping by one drive source in the recovery unit without depending on the drive force from other drive sources. In addition to the recovery mode selection, the cap member of the cap means does not move from the state in contact with the ejection port surface of the recording head during the suction recovery operation of the suction pump, and the cap means is recorded after the suction recovery is completed. Provided a recovery unit for the inkjet recording device that is completed in the recovery operation unit that can prevent positive pressure due to reverse rotation of the tube pump until the cap member is fully retracted from the discharge port surface even when retracted from the discharge port surface of the head Is done.
[0050]
Further, the suction means is driven to rotate from the drive source, and a tube communicating with the discharge port of the recording means is deformed by a pressure roller, thereby generating a negative pressure at the discharge port and discharging ink from the discharge port. This is a tube pump, and when the pressure roller is driven in the direction opposite to the tube pressure rotation direction, the pressure roller moves in the direction to relieve the tube pressurizing force. When performing recovery operations other than the suction recovery operation, the residual ink in the tube and the air in the tube do not flow backward due to the reverse rotation of the tube pump. A recovery unit is provided.
[0051]
Further, the suction means is driven to rotate from the drive source, and a tube communicating with the discharge port of the recording means is deformed by a pressure roller, thereby generating a negative pressure at the discharge port and discharging ink from the discharge port. When the ink discharge suction recovery is performed by the suction unit, the atmosphere communication valve is opened by driving the drive source in one direction, and the pressure roller constituting the suction unit is driven by the reverse drive. Since each suction recovery mode is selected after pressing the suction tube of the pump and the suction operation of each mode is performed, the suction operation always starts from the state where the position of the pressure roller before suction is pressed against the tube. Therefore, by specifying the amount of rotation of the tube pump from the above state, it is possible to suck ink with little variation without having a roller position detection sensor. More stable ink jet recording apparatus for the recovery unit is provided.
[0052]
In the above-described embodiment, the serial recording type inkjet recording apparatus that records while moving the recording unit relative to the recording medium has been described as an example. However, the present invention is not limited to the full width of the recording medium. Alternatively, the present invention can be similarly applied to a line recording type ink jet recording apparatus that records only by sub-scanning using a line type recording means having a length that covers a part, and can achieve the same effect. It is. The present invention also provides a gradation using a recording apparatus using a single recording means, a color recording apparatus using a plurality of recording means for recording with different color inks, or a plurality of recording means for recording with the same color and different densities. The present invention can be similarly applied to a recording apparatus and further to a recording apparatus that combines these, and the same effect can be achieved.
[0053]
Further, the present invention provides a recording head including a configuration using a replaceable ink cartridge in which a recording head and an ink tank are integrated, a configuration in which the recording head and the ink tank are separated, and a connection between them using an ink supply tube or the like. The present invention can be similarly applied to any arrangement of the ink tanks, and the same effect can be obtained. The present invention can also be applied to a case where the ink jet recording apparatus uses a recording means that uses an electromechanical transducer such as a piezo element. In particular, the ink is ejected using thermal energy. In the ink jet recording apparatus using the recording means of the above system, an excellent effect is brought about. This is because such a system can achieve higher recording density and higher definition.
[0054]
【The invention's effect】
According to the present invention, an operation such as applying a positive pressure by reverse rotation of the suction means in the cap during capping by one drive source in the recovery unit without depending on the drive force from another drive source. Conventional processing such as applying multiple positive pressures by reverse rotation of the suction means until the cap is fully retracted from the discharge port surface after completion of suction recovery. By eliminating the need for an operation, there is provided an ink jet recording apparatus that can eliminate the operation of moving the cap from the state of being in contact with the discharge port surface during the suction recovery operation.
[Brief description of the drawings]
FIG. 1 is a schematic perspective view showing a schematic configuration of an ink jet recording apparatus provided with an embodiment of a recovery unit to which the present invention is applied.
FIG. 2 is a schematic perspective view showing a recovery unit of the ink jet recording apparatus of FIG. 1 as viewed obliquely from above.
FIG. 3 is a schematic exploded perspective view showing the internal structure of the recovery unit in FIG.
4 is a schematic side view showing a gear train as a transmission mechanism provided in the recovery unit of FIG. 2; FIG.
FIG. 5 is a cross-sectional view showing a state immediately after the drive transmission by the pump gear to the tube pump as the suction means in one embodiment of the recovery unit to which the present invention is applied is released.
6 is a cross-sectional view showing a state immediately before the drive by the pump gear is transmitted to the tube pump of FIG.
7 is a cross-sectional view showing a state in which a driving operation by a pump gear is transmitted to the tube pump of FIG. 5 and a suction operation is performed.
FIG. 8 is a cross-sectional view showing a state immediately after the pressure roller of the tube pump as the suction means in the embodiment of the recovery unit to which the present invention is applied presses the tube and the drive transmission by the pump gear is released. is there.
9 is a cross-sectional view showing a state immediately before the drive by the pump gear is transmitted to the tube pump of FIG.
10 is a cross-sectional view showing a state in which driving by a pump gear is transmitted to the tube pump of FIG. 9 and a pressure roller is in a released state.
FIG. 11 is a schematic perspective view showing a state in which both the Bk atmospheric communication valve and the Color atmospheric communication valve of the capping means in the embodiment of the recovery unit to which the present invention is applied are closed (cap closed state); .
12 is a schematic perspective view showing a state in which both the Bk atmospheric communication valve and the Color atmospheric communication valve of the capping means in the recovery unit of FIG. 11 are opened (empty suction, colloidal removal state).
13 is a schematic perspective view showing a state in which the color atmosphere communication valve of the capping means in the recovery unit of FIG. 11 is opened and the Bk atmosphere communication valve is closed (Bk suction state). .
14 is a schematic perspective view showing a state (Color suction state) in which the Color atmospheric communication valve is closed and the Bk atmospheric communication valve is opened among the atmospheric communication valves of the capping means in the recovery unit of FIG. 11; .
FIG. 15 is a cross-sectional view showing a state where a pressure roller of a tube pump as a suction unit in a recovery unit to which the present invention is applied is in a released state and drive transmission by a pump gear is released.
16 is a cross-sectional view showing a state in which the tube pump in FIG. 15 receives drive transmission from the pump gear and presses the pressure roller of the suction means against the tube.
FIG. 17 is a chart showing each state during a suction mode selection operation of a cap of a capping unit and an atmospheric communication valve in an embodiment of a recovery unit to which the present invention is applied.
FIG. 18 is a flowchart showing a sequence of a general suction recovery operation in an embodiment of the recovery unit to which the present invention is applied.
19 is a partial perspective view schematically showing the structure of the ink discharge portion of the recording means in FIG. 1. FIG.
[Explanation of symbols]
1 Inkjet recording device
2 Carriage
3 Recording means (recording head)
4 Transmission mechanism
5 Paper feed mechanism
6 Ink cartridge
7 Drive belt
8 scale
9 Chassis
10 Recovery unit (recovery device)
11 Capping means
12 Wiping means
13 Guide shaft
14 Transport roller
15 Pinch roller
16 Pinch roller guide
17 Conveyor roller gear
18 Intermediate gear
19 Discharge roller gear
20 Recovery base
21 Spur Roller
23 Discharge port surface
24 PG gear
25 PG gear
26 PG gear
27 Pump gear
28 One-way drive transmission means (One-way clutch gear)
29 CR lock lever
30 Pressure roller holder guide
31 Pressure roller holder
32 tube (suction tube)
33 Pressure roller
34 Cap base
35 cap
36 Cap holder
37 Capping means lift lever
38 cams
39 Cap means lifting lever biasing spring
40 Cam position detection sensor
41 Pump gear trigger boss
42a Pump gear trigger rib
42b Pump gear trigger rib
43 Pressure roller pressure contact point
44 Cap absorber
45 Atmospheric communication tube
46a Air communication valve
46b Air communication valve
47 Air communication hole
48 Suction means (suction pump, tube pump)
49 Discharge port
50 Common liquid chamber
51 liquid channel
52 Electrothermal converter
A Carriage reciprocating direction
L Roller pressurizing rotation direction of tube pump
M1 Carriage drive motor (drive source)
M2 transport motor (drive source)
M3 recovery motor (drive source, PG motor)
P Recording material (recording paper, etc.)
R Tube pump roller release rotation direction

Claims (4)

A cap for capping the ejection port surface of a recording head that performs recording by discharging ink, a suction tube communicating with the cap, and a roller for pressing the suction tube and generating a negative pressure in the suction tube A roller holder that rotatably supports the roller, an atmospheric communication valve for switching the inside of the cap to an atmospheric communication state or a sealed state, and a motor that can rotate forward and backward, and when the motor rotates forward, the roller holder When the roller rotates in the first direction, the roller is pressed against the tube and the tube is squeezed. When the motor reverses, the roller holder rotates in a second direction opposite to the first direction. An ink jet recording apparatus in which the pressing of the roller against the tube is released,
When the rotation direction of the motor is switched from normal rotation to reverse rotation, before the drive of the motor is transmitted to the roller holder, the atmospheric communication valve is driven so that the inside of the cap is sealed from the atmospheric communication state to the sealed state. An ink jet recording apparatus characterized by switching to   A pump gear for transmitting the drive of the motor; and a roller holder guide for transmitting the rotation of the pump gear to the roller holder. The pump gear has two ribs on a side surface, and the roller holder guide is It has a boss that enters a space between two ribs, and the rib that contacts the boss when the motor rotates forward is different from the rib that contacts the boss when the motor rotates backward. The inkjet recording apparatus according to claim 1.   Driven by the motor to drive the atmospheric communication valve and to move the cap with respect to the discharge port surface, and when the motor reverses, the drive is transmitted to the cam. The inkjet recording apparatus according to claim 1, further comprising a one-way transmission unit that does not transmit the drive to the cam when it rotates forward. A cap for capping the ejection port surface of a recording head that performs recording by discharging ink, a suction tube communicating with the cap, and a roller for pressing the suction tube and generating a negative pressure in the suction tube And a roller holder that rotatably supports the roller, an atmospheric communication valve for switching the inside of the cap to an atmospheric communication state or a sealed state, and a motor capable of forward and reverse rotation. ,
A first reversing step of reversing the motor to bring the cap into contact with the discharge port surface and driving the atmosphere communicating valve to bring the inside of the cap into the atmosphere communicating state;
After the first reverse rotation step, the first normal rotation step of rotating the motor forward and rotating the roller holder in a first direction to press the roller against the suction tube;
After the first forward rotation step, the motor is reversely rotated again, and the atmospheric communication valve is driven without rotating the roller holder to switch the inside of the cap from the atmospheric communication state to the sealed state. Process,
After the second reversing step, the motor is rotated forward again, and the suction tube is squeezed with the roller.
A suction method for an ink jet recording apparatus, comprising:

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