Wiper mechanism

Abstract

To inhibit adhesion of an ink to an inkjet head side surface in a wiper mechanism.SOLUTION: A wiper mechanism 1 includes first wipers 11, 51, 61, 71 and second wipers 12, 52, 62, 72 which wipe a head surface S provided with nozzle arrays 111a of an inkjet head 111 in a wipe direction D1. The first wipers 11, 51, 61, 71 wipe the head surface S at the downstream side relative to the second wipers 12, 52, 62, 72 in the wipe direction D1. Widths W11, W51, W61, W71, W12, W52, W62, W72 in a width direction D2 orthogonal to the wipe direction D1 of tips of the first wipers 11, 51, 61, 71 and the second wipers 12, 52, 62, 72 are shorter than a head surface width W1 in the width direction D2 of the head surface S.SELECTED DRAWING: Figure 9A

Description

[Technical field]

[0001] The present invention relates to a wiper mechanism for wiping an inkjet head. [Background technology]

[0002] Conventionally, a method for cleaning the nozzle surface of an inkjet head on which the nozzle rows are provided involves pushing out the ink inside the inkjet head with pressure (purging operation) and wiping the ink off the nozzle surface with a wiper. A wiper for wiping off the ink in this way is used that wipes the entire head surface (head bottom surface), including the nozzle surface and the bottom surface of the mask plate around the nozzle surface, in the width direction perpendicular to the wiping direction.

[0003] As an inkjet printing device using a wiper, for example, an inkjet printing device has been proposed in which a single wiper performs a first action of wiping ink while separated from the ejection surface (head surface) of the inkjet head, and a second action of wiping ink while in contact with the ejection surface in order to reduce wiping unevenness (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2017-24199 A Summary of the Invention [Problem to be solved by the invention]

[0005] As described above, because the wiper wipes the entire head surface, repeated cleaning causes the ink to overflow from the head surface in the width direction, gradually increasing the amount of ink adhering to the side of the mask plate (side of the inkjet head). Eventually, the amount of ink adhering to the side of the mask plate becomes saturated, so repeated cleaning does not reduce the amount of ink adhering.

[0006] If ink remains on the side surface of the mask plate in this way, the paper will come into contact with the inkjet head or ink droplets will fall, causing the paper to become soiled.

[0007] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a wiper mechanism capable of suppressing adhesion of ink to the side surface of an ink-jet head. [Means for solving the problem]

[0008] In one aspect, the wiper mechanism includes a first wiper and a second wiper that wipe a head surface on which a nozzle row of an inkjet head is provided in a wiping direction, the first wiper wipes the head surface downstream in the wiping direction from the second wiper, and the width of the tips of the first wiper and the second wiper in a width direction perpendicular to the wiping direction is shorter than the head surface width in the width direction of the head surface. Effect of the Invention

[0009] According to this aspect, it is possible to suppress adhesion of ink to the side surface of the inkjet head. [Brief description of the drawings]

[0010] [Figure 1] 1 is a front view showing an internal structure of an inkjet printing apparatus according to an embodiment; [Diagram 2] FIG. 2 is a diagram illustrating a main control configuration of an inkjet printing apparatus according to an embodiment. [Diagram 3] FIG. 2 is a front view of a wiper mechanism in a wiping position according to one embodiment. [Figure 4] FIG. 2 is a plan view showing a wiper mechanism according to an embodiment. [Diagram 5] FIG. 2 is a left side view showing a first wiper, a second wiper, and an inkjet head in the embodiment. [Figure 6] FIG. 2 is a bottom view showing the inkjet head according to the embodiment. [Figure 7] 1 is a graph showing the amount of ink attached to a mask plate after wiping in a comparative example and examples 1 to 4. [Figure 8A] FIG. 2 is a front view for explaining dimensions of each part in the first embodiment. [Figure 8B] FIG. 4 is a front view for explaining the flow of ink in the first embodiment. [Figure 8C] FIG. 4 is a front view illustrating ink adhering to the inkjet head after wiping in the first embodiment. [Figure 9A] FIG. 11 is a front view for explaining dimensions of each part in the second embodiment. [Figure 9B] FIG. 11 is a front view for explaining the flow of ink in the second embodiment. [Figure 9C] FIG. 11 is a front view illustrating ink adhering to the inkjet head after wiping in Example 2. [Figure 10A] FIG. 11 is a front view for explaining dimensions of each part in the third embodiment. [Figure 10B] FIG. 11 is a left side view showing the first wiper, the second wiper, the intermediate wiper, and the inkjet head in the third embodiment. [Figure 11] FIG. 13 is a front view for explaining dimensions of each part in the fourth embodiment. [Figure 12A] FIG. 13 is a front view for explaining dimensions of each part in a comparative example. [Figure 12B] FIG. 11 is a front view for explaining the flow of ink in a comparative example. [Figure 12C] FIG. 11 is a front view illustrating ink adhering to an inkjet head after wiping in a comparative example. [Figure 12D] FIG. 11 is a left side view illustrating ink adhering to an inkjet head after wiping in a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, a wiper mechanism 1 according to an embodiment of the present invention will be described with reference to the drawings.

[0012] FIG. 1 is a front view showing the internal structure of an inkjet printing apparatus 100 according to one embodiment.

[0013] FIG. 2 is a diagram showing the main control configuration of the inkjet printing apparatus 100. As shown in FIG.

[0014] Note that the front-to-back, up-down, and left-to-right directions shown in Figure 1 and Figures 3 to 6 and Figures 8A to 12D described below are examples when the transport direction during printing of paper P, which is an example of a medium, is the rightward direction and the wiping direction D1 of the first wiper 11 and the second wiper 12 is the forward direction, and for example, the front-to-back and left-to-right directions are horizontal directions, and the up-down direction is vertical directions.

[0015] As shown in Fig. 1, the inkjet printing apparatus 100 includes a wiper mechanism 1, a printing unit 110, a suction transport unit 120, an external paper feed unit 130, internal paper feed units 141-143, transport roller pairs 151-155, and a registration roller pair 156. As shown in Fig. 2, the inkjet printing apparatus 100 further includes a control unit 161, a storage unit 162, an operation panel unit 163, a scanner 164, and a paper discharge unit 165. In Fig. 1, the transport paths extending from the external paper feed unit 130 and the internal paper feed units 141-143 to the printing unit 110 are indicated by thick solid lines.

[0016] The printing unit 110 shown in FIG. 1 has a plurality of inkjet heads 111. As shown in FIG. 4, two sets of six inkjet heads 111 are arranged in a staggered pattern along a main scanning direction (front-rear direction) perpendicular to the transport direction (right direction) of the paper P, totaling 12 inkjet heads 111. That is, one set of six inkjet heads 111 arranged along the front-rear direction are arranged with their positions shifted alternately in the left-right direction. As an example, one set of six inkjet heads 111 ejects ink of two colors (e.g., black (K) and cyan (C)), and the other set of six inkjet heads 111 ejects ink of two colors (e.g., magenta (M) and yellow (Y)) different from those of the one set.

[0017] As shown in Fig. 1, the suction transport unit 120 is disposed so as to face the printing unit 110. The suction transport unit 120 transports the paper P by a transport belt while, for example, suctioning the paper P. The suction transport unit 120 may be movable between a printing position shown in Fig. 1, a wiping position shown in Fig. 3 below the printing position, and a standby position (not shown) below the wiping position. The wiper mechanism 1 is located below the printing unit 110 during wiping as shown in Fig. 3, and is located at a position retracted from below the printing unit 110 during printing as shown in Fig. 1.

[0018] The external paper feed unit 130 and the internal paper feed units 141 to 143 each include paper feed trays 131, 141a, 142a, and 143a, scraper rollers 132, 141b, 142b, and 143b, and pickup rollers 133, 141c, 142c, and 143c.

[0019] A plurality of sheets of paper P are stacked on the paper feed trays 131, 141a, 142a, and 143a.

[0020] The scraper rollers 132, 141b, 142b, and 143b are feed rollers that feed and transport the uppermost sheet P among the multiple sheets P stacked on the sheet feed trays 131, 141a, 142a, and 143a.

[0021] The pick-up rollers 133, 141c, 142c, and 143c transport the paper P fed by the scraper rollers 132, 141b, 142b, and 143b.

[0022] The conveying roller pairs 151 to 155 are disposed on a conveying path between the internal paper feed units 141 to 143 and the registration roller pair 156.

[0023] The sheet P conveyed from the external sheet feeding unit 130 and the internal sheet feeding units 141 to 143 abuts against the pair of registration rollers 156. As a result, skew of the sheet P is corrected.

[0024] The control unit 161 shown in FIG. 2 has a processor (e.g., a CPU: Central Processing Unit) that functions as an arithmetic processing device that controls the operation of the entire inkjet printing device 100, and controls the operation of each part of the inkjet printing device 100, such as the wiper drive unit 40, the printing unit 110, and the suction transport unit 120.

[0025] The memory unit 162 is, for example, a ROM (Read Only Memory), which is a read-only semiconductor memory in which a specific control program is pre-recorded, a RAM (Random Access Memory), which is a semiconductor memory that can be written to and read at any time and is used as a working memory area as needed when the processor executes various control programs, or a hard disk device.

[0026] The operation panel unit 163 functions as an example of an input unit and a display unit of the inkjet printing apparatus 100 by having, for example, operation keys for performing various operations, a touch panel, a display for displaying various information, and the like.

[0027] The scanner 164 reads image data from a document.

[0028] Although not shown in FIG. 1, the paper discharge section 165 has a paper discharge tray on which paper P printed by the printing section 110 is stacked, and discharge rollers that discharge the paper P onto the paper discharge tray.

[0029] FIG. 3 is a front view showing the wiper mechanism 1 in the wiping position.

[0030] FIG. 4 is a plan view showing the wiper mechanism 1. As shown in FIG.

[0031] FIG. 5 is a left side view showing the first wiper 11, the second wiper 12, and the inkjet head 111. As shown in FIG.

[0032] FIG. 6 is a bottom view showing the inkjet head 111. As shown in FIG.

[0033] 3 to 6 and 8A to 12D described later, the front-rear, up-down, and left-right directions are directions in a state in which the wiper mechanism 1 is located between the printing unit 110 and the suction and transport unit 120 as shown in Fig. 3. However, for example, in a mode in which the inkjet head 111 ejects ink in a direction inclined at a specified angle from the vertically downward direction, the up-down direction in the following description also refers to a direction inclined at the above-mentioned specified angle.

[0034] As shown in FIG. 4, the wiper mechanism 1 includes a wiper unit 10, two guide portions 20, an ink receiving portion 30, and a wiper driving portion 40. The wiper unit 10 includes a wiper unit 12 and a guide portion 20. The guide portion 20 is a guide portion 20a.

[0035] The wiper unit 10 has, for example, four first wipers 11, for example, four second wipers 12, and a single wiper support member 13 that supports the first wipers 11 and the second wipers 12.

[0036] 5 are wiper blades made of an elastic body made of rubber, for example. The first wiper 11 is provided downstream of the second wiper 12 in the wiping direction D1. That is, the first wiper 11 wipes the head surface S before the second wiper 12. Note that the first wiper 11 is provided at a height that does not contact the head surface S (a length that does not allow the first wiper 11 to contact the head surface S), but since the first wiper 11 can scrape off the purged ink (ink IK) on the head surface S, it can be said that the first wiper wipes the head surface S.

[0037] The first wiper 11 and the second wiper 12 wipe a head surface S (e.g., a bottom surface) on which two nozzle rows 111a (see FIG. 6) that eject ink IK of the inkjet head 111 are provided, in a wiping direction D1 (forward direction) perpendicular to the transport direction (rightward) of the paper P. Note that the second wiper 12 is represented by hatching in each drawing to show the difference from the first wiper 11, particularly in Examples 1 to 4 described later.

[0038] 6, the head surface S includes a nozzle surface S1 formed of polyimide resin and provided with the nozzle row 111a, and a mask plate bottom surface S2 of a mask plate 111b located around the nozzle surface S1 and protecting the nozzle surface S1. The nozzle surface S1 may be treated to be ink repellent, for example by coating it with an oil repellent film.

[0039] As described above, two sets of six inkjet heads 111 are arranged in a staggered pattern, so that the inkjet heads 111 are arranged in a total of four rows in the width direction D2 (left-right direction) perpendicular to the wiping direction D1, as shown in Fig. 4. Therefore, four first wipers 11 and four second wipers 12 are arranged to wipe the head surfaces S of one row (three inkjet heads) of inkjet heads 111.

[0040] The first wiper 11 and the second wiper 12 extend from the wiper support member 13 shown in FIG. 4 in an upward direction perpendicular to the head surface S. The tip, which is the upper end of the first wiper 11 before wiping, is located below the head surface S. Therefore, as shown in FIG. 5, the first wiper 11 is provided with a length that does not allow it to contact the head surface S during wiping, and does not contact the head surface S. On the other hand, the tip, which is the upper end of the second wiper 12, extends above the head surface S (a length that wraps around the head surface S) before wiping, and wipes the head surface S in a curved state during wiping. However, the first wiper 11 may also have a tip that extends above the head surface S before wiping and wipe the head surface S in a curved state during wiping, similar to the second wiper 12. In this case, it is preferable to increase the distance between the first wiper 11 and the second wiper 12 in the wiping direction D1 to prevent the first wiper 11 and the second wiper 12 from contacting each other.

[0041] 4, the four first wipers 11 and the four second wipers 12 are integrally provided on the wiper support member 13. Note that the first wipers 11 and the second wipers 12 may be provided separately from the wiper support member 13 and attached to the wiper support member 13.

[0042] The wiper support member 13 is provided with, for example, a pair of left and right screw holes 13a, 13a penetrating therethrough in the front-rear direction.

[0043] Each of the two guide parts 20 is, for example, a screw shaft extending in the front-rear direction and is disposed so as to penetrate the screw holes 13a, 13a of the wiper support member 13. Therefore, by rotating the guide parts 20, the wiper unit 10 can move in the wiping direction D1, which is the front-rear direction, and in the return direction opposite thereto.

[0044] The ink receiver 30 receives the ink IK that falls from the inkjet head 111 together with paper powder, dust, and the like.

[0045] When the wiper mechanism 1 is tilted at the retracted position shown in Fig. 1, the ink IK in the ink receiving unit 30 flows from the discharge unit 30b of the ink receiving unit 30 through a waste liquid path (not shown) to the waste liquid storage unit. The ink receiving unit 30 has, for example, a rectangular parallelepiped shape that opens upward. Therefore, the inner bottom surface of the ink receiving unit 30 becomes the ink receiving surface 30a. The ink receiving unit 30 rotatably supports the front end of the guide unit 20.

[0046] The wiper driving section 40 has, for example, two motors 41. The motor 41 is an example of a driving means (actuator) that drives the wiper unit 10 (the first wiper 11 and the second wiper 12), and is, for example, bonded to the guide section 20 by adhesion. The motor 41 rotates the guide section 20 to move the wiper unit 10 in the front-rear direction as described above. Note that the single motor 41 may rotate the two guide sections 20 via pulleys in the drive belt, for example, by rotating the drive belt. Alternatively, only a single motor 41 and a single guide section 20 may be provided, and the single guide section 20 may move the wiper unit 10 in the front-rear direction.

[0047] Next, a wiping operation using the first wiper 11 and the second wiper 12 will be described. Note that this wiping operation may be performed, for example, every time a predetermined number of sheets are printed or every elapsed time, or based on a user's operation on the operation panel unit 163 shown in FIG.

[0048] First, before the first wiper 11 and the second wiper 12 wipe the head surface S of the inkjet head 111, as shown in Fig. 3, the suction transport unit 120 moves downward from the printing position shown in Fig. 1, and the wiper mechanism 1 moves between the printing unit 110 and the suction transport unit 120. Furthermore, the inkjet head 111 ejects purged ink (ink IK) from the nozzle row 111a as shown in Fig. 5. As a result, the ink IK ejected from the nozzle row 111a gathers and is scattered at multiple points.

[0049] After that, the first wiper 11 and the second wiper 12 move in the wiping direction D1. As a result, the ink IK and the like wiped by the first wiper 11 and the second wiper 12 (for example, the purged ink IK, the ink IK originally attached to the head surface S, and paper powder and dust contained in the ink IK) run down the first wiper 11 and the second wiper 12 and fall in the direction of gravity onto the ink receiving surface 30a of the ink receiving unit 30 shown in FIG. 4 described above.

[0050] As described above, the first wiper 11 is provided with a length that prevents it from coming into contact with the head surface S during wiping. Therefore, after being wiped by the first wiper 11, the ink IK remains as a thin liquid film on the head surface S. Thereafter, the ink IK that has become a thin liquid film is wiped by the second wiper 12.

[0051] After the first wiper 11 and the second wiper 12 wipe the head surfaces S of all the inkjet heads 111, the inkjet heads 111 drive the piezoelectric elements to eject the ink IK from each nozzle row 111a, thereby performing a flushing operation, which can improve the color mixing of the ink IK in the nozzle row 111a. Thereafter, the suction transport unit 120 shown in FIG. 3 moves downward, and the wiper mechanism 1 moves to the retracted position shown in FIG. 1. In addition, the suction transport unit 120 rises to a position close to the printing unit 110 when printing is performed, and moves further downward to a standby position when printing is not performed. Note that, it is preferable that the wiper unit 10 (the first wiper 11 and the second wiper 12) is in a state of returning to the upstream side in the wiping direction D1 in preparation for the next wiping operation at the retracted position of the wiper mechanism 1 shown in FIG. 1.

[0052] A comparative example and examples 1 to 4 shown in FIG. 7 will be described below.

[0053] <Comparative Example> Figure 12A is a front view for explaining the dimensions of each part, Figure 12B is a front view for explaining the flow of ink IK, and Figures 12C and 12D are a front view and a left side view for explaining the ink IK adhering to the inkjet head 111 after wiping.

[0054] In the first wiper 201 and the second wiper 202 in the comparative example, similarly to the above-described first wiper 11 and second wiper 12, the tip of the first wiper 201 is located below the head surface S and is not in contact with the head surface S. The tip, which is the upper end of the second wiper 202 located upstream of the first wiper 201 in the wiping direction D1, extends above the head surface S before wiping and wipes the head surface S in a curved state during wiping.

[0055] Here, as shown in FIG. 12A, the width of the head surface S in the width direction D2 is a head surface width W1, the width of the nozzle surface S1 in the width direction D2 is a nozzle surface width W2, and the distance between the two nozzle rows 111a is a nozzle row distance W3.

[0056] The width W201 in the width direction D2 of the tip (upper surface during wiping) of the first wiper 201 is equal to the nozzle surface width W2. In this specification, "equal" includes the case where the difference between the two is less than 10% of the longer width because the two do not have completely the same value due to tolerances, etc. This difference due to tolerances, etc. is preferably less than 5%. In this specification, "more than" and "less than" also include the same value. In addition, in Figures 8A to 12D (Examples 1 to 4 and this comparative example), the nozzle surface S1 is illustrated as protruding downward from the mask plate bottom surface S2, but the nozzle surface S1 may be located on the same plane as the mask plate bottom surface S2, or may be located above the mask plate bottom surface S2. Even if the nozzle surface S1 and the mask plate bottom surface S2 are not located on the same plane, the difference in height is not large, so it is possible to wipe both the nozzle surface S1 and the mask plate bottom surface S2 at the same time.

[0057] A width W202 in the width direction D2 of the tip of the second wiper 202 is longer than the head surface width W1. Therefore, the second wiper 202 protrudes to both sides of the inkjet head 111 in the width direction D2.

[0058] As shown by the thick arrows in Fig. 12B, when the ink IK is wiped off by the first wiper 201, the ink IK is pushed up to the bottom surface S2 of the mask plate and adheres to the bottom surface S2 of the mask plate. Then, the second wiper 202, which is wider than the head surface width W1, pushes up the ink IK adhered to the bottom surface S2 of the mask plate. Therefore, as shown in Fig. 12C and Fig. 12D, the ink IK flows around the side surface of the mask plate 111b and adheres to the side surface of the mask plate 111b, particularly on the downstream side in the wiping direction D1 of the mask plate 111b.

[0059] Therefore, as shown in Figure 7, when a set of the ejection operation of purging ink (ink IK) and the subsequent wiping operation was repeated 10 times without a printing operation in between, the amount of ink adhering to the mask plate 111b was large both on the bottom surface S2 of the mask plate (approximately 13 mg) and on the side surface of the mask plate 111b (approximately 8 mg).

[0060] <Example 1> FIG. 8A is a front view illustrating the dimensions of each part, FIG. 8B is a front view illustrating the flow of ink IK, and FIG. 8C is a front view illustrating ink IK adhering to inkjet head 111 after wiping.

[0061] The first wiper 11 and the second wiper 12 shown in FIG. 8A are the same as the first wiper 11 and the second wiper 12 shown in FIG. 4 and FIG. 5. The width W11 in the width direction D2 of the tip of the first wiper 11 located at the most downstream in the wiping direction D1 is equal to the width W12 in the width direction D2 of the tip of the second wiper 12 located at the most upstream in the wiping direction D1. The widths W11 and W12 of the first wiper 11 and the second wiper 12 are equal to the nozzle face width W2 of the nozzle face S1 and are shorter than the head face width W1. Therefore, the first wiper 11 and the second wiper 12 are located closer to the center than both the left and right ends of the inkjet head 111 in the width direction D2. It is preferable that the first wiper 11 wipes at least a part of the ejection area of ​​the ink IK, such as the nozzles of the nozzle row 111a, and it is preferable that the second wiper 12 wipes the entire nozzle face S1. Therefore, it is desirable that the width W11 of the tip of the first wiper 11 is equal to or larger than the nozzle row interval W3 and smaller than the head face width W1, and it is desirable that the width W12 of the tip of the second wiper 12 is equal to or larger than the nozzle face width W2 and smaller than the head face width W1. Also, it is desirable that the width W11 of the tip of the first wiper 11 is equal to or smaller than the width W12 of the tip of the second wiper 12.

[0062] As the flow of ink IK is shown by the thick arrows in Fig. 8B, when ink IK is wiped off by the first wiper 11, the ink IK moves to both sides in the width direction D2 and adheres to the bottom surface S2 of the mask plate. However, since the width W12 of the tip of the second wiper 12 is shorter than the head surface width W1, the ink IK is less likely to adhere to the side surface of the mask plate 111b, as shown in Fig. 8C. Also, since the width W12 of the tip of the second wiper 12 is equal to the nozzle surface width W2, the second wiper 12 does not come into contact with the bottom surface S2 of the mask plate (both sides in the width direction D2 of the nozzle surface S1), and therefore the ink IK does not adhere to the side surface of the mask plate 111b.

[0063] Therefore, the above-mentioned ink adhesion amount shown in FIG. 7 was not detected on the side surface of the mask plate 111b, and did not increase on the mask plate bottom surface S2 (about 13 mg) as compared to the comparative example.

[0064] <Example 2> FIG. 9A is a front view illustrating the dimensions of each part, FIG. 9B is a front view illustrating the flow of ink IK, and FIG. 9C is a front view illustrating ink IK adhering to inkjet head 111 after wiping.

[0065] The first wiper 51 and the second wiper 52 shown in FIG. 9A are different from the first wiper 11 and the second wiper 12 of the first embodiment described above only in the width W51 of the leading end of the first wiper 51.

[0066] The width W51 of the tip of the first wiper 51 in the width direction D2 is narrower than the width W52 of the tip of the second wiper 52 in the width direction D2, and is equivalent to the nozzle row interval W3 between the two nozzle rows 111a. The width W52 of the tip of the second wiper 52 is also equivalent to the nozzle face width W2 of the nozzle face S1. Therefore, in this second embodiment as well, the first wiper 51 and the second wiper 52 are located closer to the center of the inkjet head 111 in the width direction D2 than either the left or right end.

[0067] As shown by the thick arrows in Fig. 9B, when the ink IK is wiped off by the first wiper 51, the first wiper 51 does not spread the ink IK toward the bottom surface S2 of the mask plate, so the amount of ink IK adhering to the bottom surface S2 of the mask plate is reduced compared to the case where the width W51 of the tip of the first wiper 51 is equal to the nozzle surface width W2 (Example 1). In addition, the second wiper 52 does not touch the bottom surface S2 of the mask plate (both sides in the width direction D2 of the nozzle surface S1). Therefore, as shown in Fig. 9C, the ink IK does not adhere to the side surface of the mask plate 111b.

[0068] Therefore, the above-mentioned ink adhesion amount shown in FIG. 7 was not detected on the side surface of the mask plate 111b, and was reduced on the mask plate bottom surface S2 (about 11 mg) compared to the comparative example and example 1.

[0069] <Example 3> 10A is a front view for explaining the dimensions of each part, and FIG. 10B is a left side view showing first wiper 61, second wiper 62, intermediate wiper 63, and inkjet head 111. As shown in FIG.

[0070] As shown in FIG. 10B, the intermediate wiper 63 is disposed between the first wiper 61 and the second wiper 62 in the wiping direction D1, and wipes the head surface S in the wiping direction D1.

[0071] The first wiper 61 and the second wiper 62 can be the same as the first wiper 11 and the second wiper 12 of the first embodiment. The tip of the intermediate wiper 63 is located below the head surface S, like the first wiper 61. The widths W61, W62, and W63 in the width direction D2 of the tips of the first wiper 61, the second wiper 62, and the intermediate wiper 63 are equal to each other and are equal to the nozzle surface width W2 of the nozzle surface S1, and are shorter than the head surface width W1. Therefore, in this embodiment 3 as well, the first wiper 61, the second wiper 62, and the intermediate wiper 63 are located closer to the center than both the left and right ends of the inkjet head 111 in the width direction D2. It is desirable that the width W63 of the tip of the intermediate wiper 63 is equal to or greater than the nozzle row interval W3 and less than the head surface width W1. It is preferable that the width W61 of the tip of the first wiper 61 is equal to or smaller than the width W63 of the tip of the intermediate wiper 63, and the width W63 of the tip of the intermediate wiper 63 is equal to or smaller than the width W12 of the tip of the second wiper 12.

[0072] The tip of the intermediate wiper 63 may extend above the head surface S before wiping and may wipe the head surface S in a curved state during wiping. In this case, the interval between the second wiper 62 and the intermediate wiper 63 in the wiping direction D1 may be set so that the intermediate wiper 63 does not come into contact with the second wiper 62 in particular. Also, a plurality of intermediate wipers 63 may be arranged side by side in the wiping direction D1. In this case, the plurality of intermediate wipers 63 may include one whose tip is located below the head surface S (for example, the intermediate wiper 63 on the downstream side in the wiping direction D1) and one whose tip is located above the head surface S before wiping (for example, the intermediate wiper 63 on the upstream side in the wiping direction D1).

[0073] In this embodiment 3, compared to the embodiment 1, the intermediate wiper 63 is disposed, and therefore the ink IK is less likely to spread onto the mask plate bottom surface S2 by the second wiper 62. Therefore, the ink IK does not adhere to the side surface of the mask plate 111b, and the amount of ink IK that adheres to the mask plate bottom surface S2 is also reduced.

[0074] Therefore, the above-mentioned ink adhesion amount shown in FIG. 7 was not detected on the side surface of the mask plate 111b, and was reduced in the bottom surface S2 of the mask plate (about 7 mg) compared to Example 1.

[0075] <Example 4> FIG. 11 is a front view for explaining the dimensions of each part.

[0076] The first wiper 71, second wiper 72, and intermediate wiper 73 shown in Figure 11 differ from the first wiper 61, second wiper 62, and intermediate wiper 63 of the above-mentioned Example 3 only in the widths W71, W73 of the tips of the first wiper 71 and intermediate wiper 73.

[0077] The widths W71, W73 of the tips of the first wiper 71 and the intermediate wiper 73 in the width direction D2 are equal to each other and are equal to the nozzle row interval W3 between the two nozzle rows 111a. Therefore, in this fourth embodiment as well, the first wiper 71, the second wiper 72, and the intermediate wiper 73 are located closer to the center of the inkjet head 111 in the width direction D2 than either the left or right end.

[0078] In this embodiment 4, the widths W71, W73 of the tips of the first wiper 71 and the intermediate wiper 73 are equivalent to the nozzle row interval W3, so the amount of ink IK that adheres to the mask plate bottom surface S2 is reduced compared to embodiment 3 in which the width is equivalent to the nozzle face width W2. Also, compared to embodiment 2 in which the intermediate wiper 73 is not provided, the ink IK is less likely to spread to the mask plate bottom surface S2 due to the presence of the intermediate wiper 73 by the second wiper 72. As a result, the ink IK does not adhere to the side surface of the mask plate 111b, and does not adhere to either side of the mask plate bottom surface S2 in the width direction D2 of the nozzle surface S1.

[0079] Therefore, the above-mentioned ink adhesion amount shown in Fig. 7 was not detected on the side surface of the mask plate 111b, and was reduced on the mask plate bottom surface S2 (about 5 mg) compared to Examples 1 to 3. As described above, the ink IK was not adhered to both sides of the nozzle surface S1 in the width direction D2 of the mask plate bottom surface S2, and therefore the ink adhesion amount on the mask plate bottom surface S2 shown in Fig. 7 is adhered to the areas before and after the nozzle surface S1 in the wipe direction D1.

[0080] In the present embodiment described above, the wiper mechanism 1 includes a first wiper 11 (similar to the first wipers 51, 61, and 71) and a second wiper 12 (similar to the second wipers 52, 62, and 72) that wipe a head surface S on which the nozzle row 111a of the inkjet head 111 is provided in a wiping direction D1. The first wiper 11 wipes the head surface S downstream of the second wiper 12 in the wiping direction D1. Widths W11 and W12 of the tips of the first wiper 11 and the second wiper 12 in a width direction D2 perpendicular to the wiping direction D1 are shorter than a head surface width W1 in the width direction D2 of the head surface S.

[0081] As a result, first, the head surface S is wiped by the first wiper 11 and the second wiper 12 arranged in the wiping direction D1, and thus the ink IK can be wiped more reliably than in a mode in which the head surface S is wiped by a single wiper. Furthermore, even if the ink IK wiped by the first wiper 11 adheres to the bottom surface S2 of the mask plate, the second wiper 12 does not wipe the entire head surface S in the width direction D2, so that the ink IK adhered to the bottom surface S2 of the mask plate is less likely to be pushed up to the side surface of the mask plate 111b. Thus, according to the present embodiment, adhesion of the ink IK to the side surface of the mask plate 111b (the side surface of the inkjet head 111) can be suppressed. By suppressing the adhesion of the ink IK to the side surface of the mask plate 111b in this way, the paper P is less likely to be soiled even if the paper P comes into contact with the inkjet head 111. Furthermore, the ink IK drops are less likely to fall from the side surface of the mask plate 111b, so that the paper P is less likely to be soiled.

[0082] In this embodiment, the head surface S includes a nozzle surface S1 on which the nozzle row 111a is provided, and a mask plate bottom surface S2 located around the nozzle surface S1. The width W11 of the tip of the first wiper 11 (the same applies to the first wipers 51, 61, and 71) is equal to or smaller than the nozzle surface width W2 in the width direction D2 of the nozzle surface S1. The width W12 of the tip of the second wiper 12 (the same applies to the second wipers 52, 62, and 72) is equal to or larger than the nozzle surface width W2 and smaller than the head surface width W1.

[0083] This makes it difficult for the first wiper 11 to spread the ink IK on the nozzle surface S1 toward the bottom surface S2 of the mask plate, thereby suppressing adhesion of the ink IK to the bottom surface S2 of the mask plate. Also, the second wiper 12 can reliably wipe the ink IK from the nozzle surface S1.

[0084] In the present embodiment, the intermediate wipers 63, 73 of Example 3 (FIGS. 10A and 10B) and Example 4 (FIG. 11) are disposed between the first wipers 61, 71 and the second wipers 62, 72 in the wiping direction D1, and wipe the head surface S in the wiping direction D1. The widths W63, W73 of the tips of the intermediate wipers 63, 73 in the width direction D2 are less than the head surface width W1.

[0085] Therefore, the ink IK is less likely to spread onto the bottom surface S2 of the mask plate when the intermediate wipers 63 and 73 wipe off the ink IK. This makes it possible to further prevent the ink IK from adhering to the bottom surface S2 of the mask plate and the side surface of the mask plate 111b.

[0086] Furthermore, in this embodiment, two nozzle rows 111a are arranged on the nozzle surface S1 at a distance W3 in the width direction D2, and the widths W51, W71 of the tips of the first wipers 51, 71 in Example 2 (Figures 9A to 9C) and Example 4 (Figure 11) are equal to the nozzle row distance W3 between the two nozzle rows 111a.

[0087] Therefore, by the first wipers 51 and 71 wiping the ink IK discharged from the nozzle row 111a only in a small area of ​​the nozzle surface S1, the ink IK on the nozzle surface S1 is less likely to spread toward the mask plate bottom surface S2. This makes it possible to further suppress adhesion of the ink IK to the mask plate bottom surface S2 and the side surface of the mask plate 111b.

[0088] In this embodiment, the width W12 of the tip of the second wiper 12 (the same applies to the second wipers 52, 62, and 72) is equal to the nozzle surface width W2.

[0089] Therefore, while the second wiper 12 reliably wipes the ink IK from the nozzle surface S1, compared to a mode in which the width W12 of the tip of the second wiper 12 exceeds the nozzle surface width W2, the ink IK is less likely to spread onto the mask plate bottom surface S2 by wiping with the second wiper 12. Therefore, adhesion of the ink IK to the mask plate bottom surface S2 and the side surface of the mask plate 111b can be further suppressed.

[0090] In this embodiment, the first wiper 11 (the same goes for the first wipers 51, 61, and 71) is located below the head surface S (nozzle surface S1) and is provided with a length that prevents it from coming into contact with the head surface S.

[0091] This makes it possible to prevent damage to the nozzle surface S1 (oil-repellent film) and maintain the durability of the nozzle surface S1. Even if the first wiper 11 has a length that allows it to contact the head surface S, if the first wiper 11 contacts the head surface S with a weaker contact pressure than the second wiper 12, it is possible to prevent damage to the nozzle surface S1 to a certain extent.

[0092] The present invention is not limited to the above-described embodiment as it is, and the components can be modified and embodied without departing from the gist of the invention in the implementation stage. In addition, various inventions can be formed by appropriate combinations of the multiple components disclosed in the above-described embodiment. For example, all the components shown in the embodiment may be appropriately combined. Of course, various modifications and applications are possible without departing from the spirit of the invention. The invention described in the claims at the time of filing of this application is appended below.

[0093] [Appendix 1] a first wiper and a second wiper for wiping a head surface on which a nozzle row of the inkjet head is provided in a wiping direction; the first wiper wipes the head surface downstream of the second wiper in the wiping direction, The width of the tip of the first wiper and the tip of the second wiper in a width direction perpendicular to the wiping direction is shorter than a head surface width of the head surface in the width direction. A wiper mechanism comprising:

[0094] [Appendix 2] the head surface includes a nozzle surface on which the nozzle row is provided and a bottom surface of a mask plate located around the nozzle surface, a width of the tip of the first wiper is equal to or smaller than a nozzle face width in the width direction of the nozzle face, The width of the tip of the second wiper is equal to or greater than the nozzle face width and less than the head face width. 2. The wiper mechanism according to claim 1 .

[0095] [Appendix 3] an intermediate wiper disposed between the first wiper and the second wiper in the wiping direction and configured to wipe the head surface in the wiping direction; The width of the tip of the intermediate wiper in the width direction is less than the head surface width. 3. The wiper mechanism according to claim 2.

[0096] [Appendix 4] The nozzle surface has two nozzle rows arranged at an interval in the width direction, The width of the tip of the first wiper is equal to the interval between the two nozzle rows. 4. The wiper mechanism according to claim 2 or 3. [Explanation of symbols]

[0097] 1 Wiper mechanism 10 Wiper unit 11 First wiper 11a Tip 11b Cutout part 12 Second wiper 12a Tip 13 Wiper support member 13a screw hole 20 Guide section 30 Ink receiver 30a Ink receiving surface 30b Discharge section 40 Wiper drive unit 41 Motor 51,61,71 First wiper 52,62,72 Second wiper 63,73 Intermediate wiper 100 Inkjet printing device 110 Printing Department 111 Inkjet head 111a Nozzle row 111b Mask plate 120 Suction conveying section 130 External paper feed section 131 Paper feed tray 132 Scraper roller 133 Pickup roller 141,142,143 Internal paper feed section 141a, 142a, 143a Paper feed tray 141b, 142b, 143b Scraper roller 141c, 142c, 143c Pickup roller 151~155 Conveyor roller pair 156 Registration roller pair 161 Control Unit 162 Storage section 163 Operation panel section 164 Scanner 165 Paper output section 201 First wiper 202 Second wiper D1 Wipe Direction D2 width direction IK Ink P paper S head surface S1 Nozzle surface S2 Mask plate bottom W1 Head face width W2 Nozzle face width W3 Nozzle row spacing W11, W51, W61, W71, W201 Width of first wiper W12,W52,W62,W72,W202 Second wiper width W63, W73 Width of third wiper

Claims

1. a first wiper and a second wiper for wiping a head surface on which a nozzle row of the inkjet head is provided in a wiping direction; the first wiper wipes the head surface downstream of the second wiper in the wiping direction, The width of the tip of the first wiper and the tip of the second wiper in a width direction perpendicular to the wiping direction is shorter than a head surface width of the head surface in the width direction. A wiper mechanism comprising:

2. the head surface includes a nozzle surface on which the nozzle row is provided and a bottom surface of a mask plate located around the nozzle surface, a width of the tip of the first wiper is equal to or smaller than a nozzle face width in the width direction of the nozzle face, The width of the tip of the second wiper is equal to or greater than the nozzle face width and less than the head face width.

2. The wiper mechanism according to claim 1.

3. an intermediate wiper disposed between the first wiper and the second wiper in the wiping direction and configured to wipe the head surface in the wiping direction; The width of the tip of the intermediate wiper in the width direction is less than the head surface width.

3. The wiper mechanism according to claim 2.

4. The nozzle surface has two nozzle rows arranged at an interval in the width direction, The width of the tip of the first wiper is equal to the interval between the two nozzle rows.

4. The wiper mechanism according to claim 2 or 3.

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