JP5730486B2 - Head cleaning device, head cleaning method, and ink jet printer - Google Patents

Description

  The present invention relates to a head cleaning device and a head cleaning method for cleaning an ink jet head, and an ink jet printer including the head cleaning device.

  In general, in an inkjet printer, the inkjet head is periodically cleaned in order to prevent nozzle clogging of the inkjet head.

  In the cleaning of the ink jet head, for example, a cleaning nozzle head communicated with a suction pump is pressed against the ink jet head, and ink is sucked from the discharge nozzle to remove aggregates and the like clogged in the nozzle.

JP 2007-276374 A

  By the way, some of the ink droplets ejected from each ejection nozzle of the ink jet head become a mist-like mist and float in the air. When the floating mist adheres to the nozzle surface, it becomes dirty on the nozzle surface, causing ink ejection failure and nozzle omission. In particular, when printing is performed in a high gap state in which the separation distance (gap) of the nozzle surface with respect to the medium is long, the flight distance and the flight time of the ink ejected from each ejection nozzle are increased, and the occurrence of mist increases. When printing on a three-dimensional medium, the gap between the medium and the nozzle surface may be larger than when printing on a sheet-like (planar) medium. For example, the gap may be 50 mm or more. is there. In addition, when UV ink that is cured by ultraviolet irradiation is used, the ultraviolet light emitted from the UV lamp reaches the nozzle surface, and the UV ink attached to the nozzle surface is fixed to the nozzle surface. It becomes even more serious.

  In Patent Document 1, it is described that the nozzle surface is wiped with a cleaning member infiltrated with a cleaning liquid. However, in this method, aggregates clogged in each discharge nozzle cannot be removed. Dirt adhering to the surface cannot be removed sufficiently.

  Therefore, an object of the present invention is to provide a head cleaning device, a head cleaning method, and an inkjet printer that can remove aggregates clogged in a nozzle with a simple configuration and can remove dirt adhered to the nozzle surface. .

  A head cleaning device according to the present invention is a head cleaning device that cleans an inkjet head having a nozzle surface on which a plurality of discharge nozzles are formed, and includes a suction unit that generates suction force, and a cleaning liquid storage container that stores cleaning liquid. And a cleaning member formed in contact with the inkjet head, and a switching unit that communicates any one of the suction unit and the cleaning liquid storage container with the cleaning nozzle of the cleaning member.

  According to the head cleaning apparatus of the present invention, the suction unit and the cleaning nozzle are communicated by the switching unit, so that the suction force generated by the suction unit causes the clogging of the discharge nozzle and the dirt adhered to the nozzle surface. The nozzle surface of the inkjet head can be wetted with the cleaning liquid sent out from the cleaning liquid storage container by connecting the cleaning liquid storage container and the cleaning nozzle by the switching means. In this way, the inkjet head can be wetted with a cleaning liquid and the inkjet head can be sucked with a single cleaning nozzle, so that aggregates clogged in the discharge nozzle can be removed with a simple configuration and dirt attached to the nozzle surface can be removed. Can be removed.

  In this case, it is preferable that the cleaning liquid storage container is disposed above the cleaning member in the vertical direction. Thus, by disposing the cleaning liquid storage container above the cleaning member in the vertical direction, it is possible to send the cleaning liquid stored in the cleaning liquid storage container to the cleaning nozzle without providing a separate means for sending out the cleaning liquid.

A head cleaning method according to the present invention is a head cleaning method using the above-described head cleaning device, wherein the cleaning liquid storage container and the cleaning nozzle are communicated by the switching means, and the cleaning liquid stored in the cleaning liquid storage container is cleaned. Then, the suction means and the cleaning nozzle are communicated by the switching means, and the inkjet head is sucked from the cleaning nozzle by the suction force generated by the suction means.

  According to the head cleaning method of the present invention, it is possible to easily remove dirt adhered to the nozzle surface by wetting the nozzle surface with the cleaning liquid before sucking the inkjet head, thereby improving the cleaning effect, Dirt on the nozzle surface due to mist and dirt that is about to adhere can be removed appropriately.

  An ink jet printer according to the present invention includes any one of the head cleaning devices described above. Thus, by providing any one of the head cleaning devices described above, it is possible to remove the aggregates clogged in the discharge nozzle with a simple configuration and remove the dirt adhered to the nozzle surface.

  According to the present invention, it is possible to remove aggregates clogged in the nozzle with a simple configuration and remove ink adhered to the nozzle surface.

1 is a schematic configuration diagram of an inkjet printer according to an embodiment. It is a figure which shows an inkjet head, (a) has shown the bottom view, (b) has shown the IIb-IIb sectional view taken on the line of (a). It is a front view which shows the structure of a washing nozzle head. It is a figure which shows the washing | cleaning operation | movement by a head washing | cleaning apparatus. It is a figure which shows operation | movement of the washing nozzle head with respect to an inkjet head.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a head cleaning device, a head cleaning method, and an ink jet printer according to the present invention will be described below in detail with reference to the drawings. The ink jet printer according to the present embodiment ejects ink droplets from the ink jet head while moving the ink jet head in the scan direction, and conveys the recording medium in a feed direction perpendicular to the scan direction, whereby an image or the like is recorded on the recording medium. Is to be printed. In the following description, the scan direction is the Y-axis direction, the feed direction is the X-axis direction, and the same or corresponding parts are denoted by the same reference numerals.

  FIG. 1 is a schematic configuration diagram of an inkjet printer according to an embodiment. As shown in FIG. 1, an ink jet printer 1 according to this embodiment includes an ink jet head 2 that ejects ink droplets, and a head cleaning device 3 that cleans the ink jet head 2.

  The ink-jet head 2 is mounted on a carriage (not shown) held so as to be reciprocally movable in the Y-axis direction, and is capable of reciprocating in the Y-axis direction above a platen (not shown) in the vertical direction. When the inkjet head 2 reciprocates in the Y-axis direction above the recording medium placed on the platen, ink droplets are ejected from the inkjet head 2 and the recording medium is appropriately conveyed in the X-axis direction. Thus, a predetermined image can be printed on the recording medium. One end portion of the inkjet head 2 in the Y-axis direction is a cleaning position of the inkjet head 2.

  2A and 2B are diagrams showing the inkjet head, FIG. 2A shows a bottom view, and FIG. 2B shows a cross-sectional view taken along line IIb-IIb in FIG. As shown in FIG. 2, the inkjet head 2 is formed with a number of ejection nozzles 2b that eject ink droplets on a nozzle surface 2a that is directed downward in the vertical direction. The nozzle surface 2a is formed in a planar shape extending in the X-axis direction, and a large number of discharge nozzles 2b are arranged in one or a plurality of rows along the X-axis direction. In FIG. 2, a large number of discharge nozzles 2b are arranged in a line.

  The inkjet head 2 is provided with a nozzle plate 2c that supports the nozzle surface 2a from below in the vertical direction. The nozzle plate 2c is formed to have a predetermined thickness and has a rectangular opening that exposes a large number of discharge nozzles 2b. For this reason, the nozzle surface 2a on which a large number of discharge nozzles 2b are formed is arranged at a position recessed in a concave shape from the lower surface in the vertical direction of the nozzle plate 2c toward the upper side in the vertical direction. Note that the separation distance (gap) between the nozzle surface 2a and the lower surface in the vertical direction of the nozzle plate 2c is, for example, 0.2 to 0.3 mm.

  As shown in FIG. 1, the head cleaning device 3 includes a cleaning nozzle head 4, a cleaning liquid tank 5, a suction pump 6, a three-way valve 7, and a buffer container 8. The cleaning nozzle head 4 and the three-way valve 7 communicate with each other through the tube R1, the cleaning liquid tank 5 and the three-way valve 7 communicate with each other through the tube R2, and the suction pump 6 and the three-way valve 7 connect the buffer container 8 to each other. Through the tube R3 (tube R3a and tube R3b).

  The cleaning nozzle head 4 is a member that contacts the inkjet head 2 and cleans the inkjet head 2. The cleaning nozzle head 4 is disposed below the cleaning position of the inkjet head 2 and is held so as to be movable in the vertical direction in the vertical direction and so as to be movable in the X-axis direction.

  FIG. 3 is a front view showing the configuration of the cleaning nozzle head. As shown in FIG. 3, the cleaning nozzle head 4 is formed in a block shape, and a cleaning nozzle 4b penetrating the cleaning nozzle head 4 is formed through the cleaning surface 4a formed on the upper surface in the vertical direction. The cleaning surface 4a is a surface that is pressed against the nozzle plate 2c of the inkjet head 2 when the cleaning nozzle head 4 moves upward. The cleaning nozzle head 4 is made of a material having a hardness lower than that of the ink jet head 2 so as not to damage the ink jet head 2, and is preferably made of a resin such as polyethylene (PE).

  The cleaning liquid tank 5 is a storage container that stores a cleaning liquid for cleaning the inkjet head 2. That is, the cleaning liquid tank 5 supplies the stored cleaning liquid to the cleaning nozzle 4b when the tubes R1 and R2 communicate with each other by the three-way valve 7. This cleaning liquid is a liquid that removes dirt adhered to the nozzle surface 2a and aggregates clogged in the discharge nozzle 2b by dissolving ink aggregates. For this reason, it is preferable that a cleaning liquid has ink and the solvent which comprises ink as a main component.

  The cleaning liquid tank 5 is disposed vertically above the cleaning surface 4 a of the cleaning nozzle head 4. For this reason, when the cleaning nozzle 4b and the cleaning liquid tank 5 are communicated with each other, the cleaning liquid tank 5 stores the cleaning liquid due to the height difference between the cleaning liquid level stored in the cleaning liquid tank 5 and the cleaning surface 4a of the cleaning nozzle head 4. The cleaning liquid being discharged is sent to the cleaning nozzle 4b and overflows from the cleaning surface 4a. The level difference between the cleaning liquid tank 5 and the cleaning surface 4a is only required to allow the cleaning liquid to flow out from the cleaning nozzle 4b, and may be such that the cleaning liquid oozes slightly from the cleaning surface 4a.

  The suction pump 6 is a suction device that sends out gas or liquid to generate a negative pressure and causes the tube R3 to generate a suction force toward the suction pump 6 side. For this reason, the suction pump 6 sucks dirt such as ink from the inkjet head 2 by generating a suction force in the cleaning nozzle 4b when the tube R1 and the tube R3 are communicated by the three-way valve 7.

  The buffer container 8 is a buffer device that is disposed between the suction pump 6 and the three-way valve 7 to relieve fluctuations in the suction force generated from the suction pump 6. Usually, when a suction force is generated by the suction pump 6, pulsation in which the suction force fluctuates at regular intervals occurs. Therefore, in order to alleviate this pulsation and transmit a substantially constant suction force to the three-way valve 7 side, a buffer container 8 is disposed between the suction pump 6 and the three-way valve 7.

  The buffer container 8 is formed in a sealed container of a predetermined capacity, and a tube R3a disposed on the suction pump 6 side and a tube R3b disposed on the three-way valve 7 side are inserted into the buffer container 8. Yes. The opening of the tube R3a is disposed at the upper part of the buffer container 8, and the opening of the tube R3b is disposed at the lower part of the buffer container 8. For this reason, the suction force generated by the suction pump 6 is transmitted to the tube R3b after the pulsation is eased by the air space in the upper space of the buffer container 8, and the cleaning liquid that is sucked and dropped from the tube R3b to the buffer container 8 Liquid such as ink is sucked into the tube R3a from the lower part of the buffer container 8.

  The three-way valve 7 is switching means for communicating any one of the cleaning liquid tank 5 and the suction pump 6 with the cleaning nozzle 4 b of the cleaning nozzle head 4. The three-way valve 7 is composed of an electromagnetic switching valve and includes one fixed port and two switching ports. A tube R1 connected to the cleaning nozzle head 4 is connected to the fixed port, a tube R2 connected to the cleaning liquid tank 5 is connected to one switching port, and the suction pump 6 is connected to the other switching port. The connected tube R3 is connected. In the three-way valve 7, two switching ports are alternatively selected, the first state in which the cleaning nozzle 4b and the cleaning liquid tank 5 are communicated, and the second state in which the cleaning nozzle 4b and the suction pump 6 are communicated. It is possible to switch between states. In addition to the first state and the second state, the three-way valve 7 may be able to be switched to a third state in which the cleaning nozzle 4b is not communicated with either the cleaning liquid tank 5 or the suction pump 6. .

  Next, the head cleaning operation of the inkjet printer 1 will be described with reference to FIGS. FIG. 4 is a diagram illustrating a cleaning operation by the head cleaning device, and FIG. 5 is a diagram illustrating an operation of the cleaning nozzle head with respect to the inkjet head. The head cleaning operation of the inkjet printer 1 described below is performed under the control of a control unit (not shown) mainly composed of a computer including a CPU, ROM, RAM, and the like.

  In the initial state, the cleaning nozzle head 4 is moved downward in the vertical direction, and further, the cleaning liquid tank 5 and the cleaning nozzle 4b are connected so that the cleaning liquid does not leak unnecessarily from the cleaning nozzle 4b of the cleaning nozzle head 4. Keep off. The communication between the cleaning liquid tank 5 and the cleaning nozzle 4b may be interrupted by switching the three-way valve 7 to the second state so that the cleaning nozzle 4b and the suction pump 6 are in communication with each other. May be switched to the third state so that the cleaning nozzle 4b is not in communication with either the cleaning liquid tank 5 or the suction pump 6. The tube R2 is closed by an electromagnetic valve (not shown) that opens and closes the tube R2. It may be done by doing.

  In the head cleaning operation, first, the inkjet head 2 is moved to the cleaning position. Then, as shown in FIG. 4A, the cleaning nozzle head 4 is moved vertically upward, and the cleaning surface 4a is pressed against the nozzle plate 2c as shown in FIG. 4B. Then, a space A is formed by the nozzle surface 2a, the discharge nozzle 2b, the nozzle plate 2c, and the cleaning surface 4a. At this time, dirt such as ink adheres to the nozzle surface 2a and the discharge nozzle 2b is clogged with aggregates.

  When the cleaning surface 4a is pressed against the nozzle plate 2c in this way, the three-way valve 7 is switched to the first state, and the cleaning nozzle 4b and the cleaning liquid tank 5 are communicated. Then, due to the difference in level between the cleaning surface 4a and the level of the cleaning liquid stored in the cleaning liquid tank 5, the cleaning liquid stored in the cleaning liquid tank 5 is sent out to the cleaning nozzle 4b through the tube R2, the three-way valve 7 and the tube R1. It is. Then, as shown in FIG. 4C, the cleaning liquid sent to the cleaning nozzle 4b overflows from the cleaning surface 4a into the space A, and the nozzle surface 2a and the discharge nozzle 2b are immersed in the cleaning liquid. Thereby, the stain | pollution | contamination adhering to the nozzle surface 2a and the discharge nozzle 2b is melt | dissolved, and it will be in the state which is easy to remove from the nozzle surface 2a and the discharge nozzle 2b. Part of the dirt is removed from the nozzle surface 2a and the discharge nozzle 2b at this stage.

  Then, as shown in FIG. 5, the cleaning nozzle head 4 is reciprocated in the X-axis direction in this state. Accordingly, the nozzle surface 2a and the discharge nozzle 2b are cleaned while the cleaning surface 4a wipes the nozzle plate 2c, and the dirt attached to all the nozzle surfaces 2a and the discharge nozzles 2b of the inkjet head 2 is dissolved.

  When the reciprocating movement of the cleaning nozzle head 4 is completed, next, the three-way valve 7 is switched to the second state, the cleaning nozzle 4b and the suction pump 6 are communicated, and the driving of the suction pump 6 is started. Then, the suction force generated by the suction pump 6 is transmitted to the cleaning nozzle 4b through the tube R3a, the buffer container 8, the tube R3b, the three-way valve 7 and the tube R1. Then, as shown in FIG. 4D, dirt accumulated in the space A and adhering to the nozzle surface 2a, aggregates clogged in the discharge nozzle 2b, and the like are sucked and removed together with the cleaning liquid and ink by the cleaning nozzle 4b. The

  Then, as shown in FIG. 5, the cleaning nozzle head 4 is reciprocated in the X-axis direction in this state. As a result, the nozzle surface 2a and the discharge nozzle 2b are cleaned while the cleaning surface 4a wipes the nozzle plate 2c, so that dirt adhered to the entire nozzle surface 2a of the inkjet head 2 and all the discharge nozzles 2b are clogged. The object is sucked and removed to the cleaning nozzle 4b together with the cleaning liquid and ink.

  As described above, according to the ink jet printer 1 according to the present embodiment, the suction pump 6 and the cleaning nozzle 4b are communicated with each other by the three-way valve 7, so that the discharge nozzle 2b is clogged by the suction force generated by the suction pump 6. Agglomerates and dirt adhered to the nozzle surface 2a can be sucked, and the cleaning liquid tank 5 and the cleaning nozzle 4b are communicated by the three-way valve 7 so that the cleaning liquid sent from the cleaning liquid tank 5 is used for the nozzle surface of the ink jet head 2. 2a can be wetted. In this way, the inkjet head 2 can be wetted with the cleaning liquid and the inkjet head 2 can be sucked with the single cleaning nozzle 4b, so that aggregates clogged in the discharge nozzle 2b can be removed with a simple configuration and the nozzle surface 2a. Dirt adhered to the surface can be removed.

  In addition, by disposing the cleaning liquid tank 5 vertically above the cleaning nozzle head 4, the cleaning liquid stored in the cleaning liquid tank 5 can be sent to the cleaning nozzle 4b without providing a separate device for sending out the cleaning liquid.

  And since the dirt adhering to the nozzle surface 2a can be easily removed by wetting the nozzle surface 2a with the cleaning liquid before sucking the inkjet head 2, the cleaning effect is improved, and the nozzle surface 2a by the mist is improved. Dirt and dirt that is about to adhere can be removed appropriately.

  The preferred embodiment of the present invention has been described above, but the present invention is not limited to the above embodiment. For example, in the above embodiment, the supply of the cleaning liquid to the cleaning nozzle head 4 is performed by arranging the cleaning liquid tank 5 vertically above the cleaning surface of the cleaning nozzle head 4. It is good also as what is performed by forced supply by attaching a liquid-feeding pump to.

  In the above-described embodiment, the inkjet printer is described as moving the inkjet head and the recording medium relatively in the X-axis direction by conveying the recording medium in the X-axis direction. In addition, the inkjet head and the recording medium may be relatively moved in the X-axis direction by conveying the inkjet head in the X-axis direction.

  In the above embodiment, the buffer container for reducing the pulsation of the suction pump is provided between the suction pump and the three-way valve. However, if this pulsation does not cause a problem, the buffer container may not be provided.

  In the above embodiment, the cleaning nozzle head has been described as having a block shape, but is not particularly limited to a shape or the like, and may be, for example, a cap shape or a bowl shape.

DESCRIPTION OF SYMBOLS 1 ... Inkjet printer, 2 ... Inkjet head, 2a ... Nozzle surface, 2b ... Discharge nozzle, 2c ... Nozzle plate, 3 ... Head cleaning apparatus, 4 ... Cleaning nozzle head (cleaning member), 4a ... Cleaning surface, 4b ... Cleaning nozzle 5 ... Cleaning liquid tank (cleaning liquid storage container), 6 ... Suction pump (suction means), 7 ... Three-way valve (switching means), 8 ... Buffer container, A ... Space, R1 ... Tube, R2 ... Tube, R3 ... Tube, R3a ... tube, R3b ... tube.

Claims (3)

A head cleaning device for cleaning an inkjet head having a nozzle surface on which a plurality of discharge nozzles are formed,
A suction means for generating a suction force;
A cleaning liquid storage container for storing the cleaning liquid;
A cleaning member in which a cleaning nozzle is formed and brought into contact with the inkjet head;
Switching means for communicating any one of the suction means and the cleaning liquid storage container to a cleaning nozzle of the cleaning member ,
When the pre-Symbol cleaning member pressed against the ink jet head, wherein being adapted to space is formed between the cleaning member and the ink jet head, the space between the discharge nozzle and the cleaning member by the space the spaced apart to the extent that the cleaning liquid is held, the space is in communication with the outside in the direction in which the cleaning member is wipe the plurality of ejection nozzles,
The cleaning member covers a part of the row of the plurality of discharge nozzles and moves, so that the cleaning member is sent to the space from the cleaning member, and the plurality of discharge nozzles are wiped by the cleaning liquid held in the space. Is to be washed with
The head cleaning apparatus, wherein the cleaning liquid storage container is disposed above the cleaning member in a vertical direction. A head cleaning method using the head cleaning device according to claim 1,
The switching means communicates the cleaning liquid storage container and the cleaning nozzle, and sends the cleaning liquid stored in the cleaning liquid storage container to the cleaning nozzle,
Thereafter, the suction means and the cleaning nozzle are communicated by the switching means, and the inkjet head is sucked from the cleaning nozzle by the suction force generated by the suction means.   An ink jet printer comprising the head cleaning device according to claim 1.

Images