Inkjet printing apparatus

Abstract

The invention provides an ink-jet printing apparatus capable of easily attaching and detaching a recording head and suppressing deviation of printing precision as much as possible every time the recording head is attached. The present invention is an inkjet printing device (100) in which a printing unit (12) has a plurality of recording head units (H), a row block frame (22), and a biasing device (23), the biasing device (23) having: a shaft unit (30) attached to the row block frame (22); a holder part (31) attached to the shaft part (30) via a bearing part (30a1) so as to be movable up and down along the shaft part (30); a spring section (32) for biasing the holder section (31) downward; and a lock pin (33) which protrudes downward from the holder part (31), is disposed on the upper surface of the base part (21) when a force is applied, and is lifted upward when the force is released.

Description

Technical Field

[0001] The present invention relates to an inkjet printing device having a recording head capable of ejecting ink. Background Art

[0002] A line head type inkjet printing device has a fixed recording head, and printing is performed by ejecting droplets of ink from the recording head onto a print medium passing under the recording head.

[0003] In addition, generally, a plurality of recording heads are used simultaneously, and there are various mounting structures.

[0004] For example, there is known an inkjet recording device (inkjet printing device), in which a recording head substrate 12 is mounted on a carriage 9, a line recording head is mounted on the recording head substrate 12, and the line recording head is formed by arranging a plurality of short-size recording heads 11 in a staggered manner. Inkjet recording is performed on a recording body 2 located on the lower side of the carriage through the line recording head (for example, refer to patent document 1).

[0005] In this inkjet printing device, each short-sized recording head 11 (recording head) is mounted on the recording head mounting surface 27 by fastening flanges 29 a and 29 b provided on both sides of the short-sized recording head in the longitudinal direction with fixing screws 30 and 30 screwed into the recording head mounting surface 27 .

[0006] In addition, there is known an inkjet printing device in which a plurality of line recording heads are arranged in a printing direction, and the line recording head is composed of a plurality of ink nozzles arranged in a row (for example, refer to Patent Document 2).

[0007] In the inkjet printing device, a first fixing pin 17 and a second fixing pin 18 are provided for pressing the upper surfaces of flanges 5 and 7 on both sides of the line recording head 3 (recording head) for fixing. The brackets 19 and 20 fixed with the fixing pins 17 and 18 are fixed to the line recording head frame 2 by fixing bolts 21 and 22.

[0008] Prior art literature

[0009] Patent Literature:

[0010] Patent Document 1: Japanese Patent Application Publication No. 2010-173232.

[0011] Patent document 2: Japanese Patent Application Publication No. 2011-152708. Summary of the invention

[0012] Problem that the invention aims to solve

[0013] However, in the inkjet printing apparatuses described in Patent Documents 1 and 2, since the recording head is mounted with fixing screws or fixing bolts, it takes time to mount and dismount the recording head, which has the disadvantage of extremely low efficiency of maintenance work.

[0014] In addition, since the degree of tightening of the bolts will be different each time the recording head is installed, there is also a disadvantage that the printing accuracy will vary.

[0015] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a device which can easily attach and detach a recording head and can minimize the variation in printing accuracy each time the recording head is attached.

[0016] Solutions for solving problems

[0017] The inventors conducted intensive research to solve the above problems and found that the above problems can be solved by providing a force applying device for mounting the recording head on the line block frame when the printing unit applies force to the base unit toward the line block frame, thereby completing the present invention.

[0018] The present invention is an inkjet printing device, which has a printing part that can eject ink, wherein the printing part has: a plurality of recording heads, which are composed of a recording head main body and a base part arranged on the periphery of the recording head main body; a row block frame, which is used to support the base part from below; and a force-applying device, which is used to install the base part on the row block frame in a state where force is applied to the side of the row block frame, and the force-applying device has: an axis part, which is installed on the row block frame and extends in the up and down directions; a bracket part, which is installed on the axis part via a bearing part in a manner that it can move up and down along the axis part; a spring part, which is installed on the axis part and is used to apply force to the bracket part downward; and a lock pin, which is installed on the bracket part and protrudes downward from the bracket part, when force is applied, the lock pin is arranged on the upper surface of the base part, and when the force is released, the lock pin is lifted upward.

[0019] In the inkjet printing device of the present invention, it is preferred that the force applying device further includes a gripping portion, which is mounted on the bracket portion and protrudes upward from the bracket portion, and by lifting the gripping portion, the gripping portion, the bracket portion and the lock pin are lifted integrally.

[0020] In the inkjet printing device of the present invention, the bracket part is preferably installed on the shaft part via the bearing part in a manner that it can move up and down along the shaft part and rotate around the shaft part. When force is applied, the locking pin is arranged on the upper surface of the base part. When the force is released, the locking pin is lifted upward and the bracket part is rotated to arrange the locking pin in a standby position set on the upper surface of the row block frame.

[0021] At this time, it is more preferable that the standby position is a stopper hole provided on the upper surface side of the row block frame, and the upper end surface of the stopper hole is located above the lower end surface of the lock pin when the lock pin is arranged in the standby position.

[0022] In the inkjet printing device of the present invention, the urging device preferably further includes a block portion, which is provided on the bracket portion and protrudes downward from the bracket portion. When the lock pin is arranged at the standby position, the block portion is arranged on the upper surface of the line block frame.

[0023] In the inkjet printing device of the present invention, the shaft portion preferably has a small diameter shaft portion and a large diameter shaft portion, the small diameter shaft portion is cylindrical, the large diameter shaft portion is arranged on the upper portion of the small diameter shaft portion, and has a diameter larger than that of the small diameter shaft portion, the small diameter shaft portion is inserted through the spring portion, the spring portion is clamped between the large diameter shaft portion and the bracket portion, the spring portion is composed of a coil spring and a disc spring, and the disc spring is arranged on the lower side of the coil spring in a manner continuous with the coil spring.

[0024] In the inkjet printing device of the present invention, it is preferred that the base portion is positioned by abutting against a reference pin provided on the line block frame, and the urging device is attached in the positioned state.

[0025] In the inkjet printing device of the present invention, the base portion is preferably rectangular when viewed from the top surface, and a first eccentric pin is installed on the row block frame at a position where it can abut against a long side surface of the base portion, a first pressure pin is installed at a position where it can abut against another long side surface, a second eccentric pin is installed at a position where it can abut against a short side surface, and a second pressure pin is installed at a position where it can abut against another short side surface. The first pressure pin applies force to the base portion in the short side direction, and the second pressure pin applies force to the base portion in the long side direction. By rotating the first eccentric pin and / or the second eccentric pin, the position of the base portion is finely adjusted.

[0026] At this time, it is more preferable that the force applied downward to the base portion by the spring portion is smaller than the force applied laterally to the base portion by the first pressure pin or the second pressure pin.

[0027] Effects of the Invention

[0028] In the inkjet printing device of the present invention, since the printing unit includes the biasing device, the base portion of the recording head can be attached to the line block frame in a state where the base portion is biased toward the line block frame.

[0029] That is, in the urging device, since the bracket portion is urged downward by the spring portion, the base portion can be urged downward by arranging the lock pin attached to the bracket portion on the upper surface of the base portion.

[0030] In addition, in the inkjet printing device, since the bracket portion can be moved up and down along the shaft portion, the force applied to the base portion can be released by lifting the lock pin together with the bracket portion.

[0031] As described above, in the inkjet printing device, the recording head can be easily attached and detached simply by moving the lock pin up and down via the bracket portion.

[0032] Furthermore, since the force that urges the bracket portion comes from the spring portion, the same degree of force can be applied to the base portion each time the recording head portion is mounted.

[0033] Therefore, it is possible to suppress as much as possible the variation in printing accuracy each time the recording head is mounted.

[0034] In addition, in the inkjet printing device, when the bracket portion can be rotated and moved around the shaft portion, the locking pin can be lifted upward from the force application position, and the bracket portion is rotated to dispose the locking pin at a standby position provided on the upper surface of the line block frame, thereby releasing the force application. In this case, in the inkjet printing device, since the bracket portion can be laterally retracted by rotation, the recording head can be more easily installed and removed.

[0035] In addition, at this time, the standby position is a stop hole set on the upper surface side of the row block frame, and the upper end surface of the stop hole is located above the lower end surface of the lock pin when the lock pin is configured in the standby position. Accordingly, since the rotation of the lock pin configured in the standby position is suppressed by the wall around the stop hole, it can be prevented from accidentally rotating and moving to the base.

[0036] In addition, in the inkjet printing device, when the force-applying device also has a block portion arranged on the bracket portion, by arranging the block portion on the upper surface of the row block frame when the lock pin is arranged in the standby position, the lower surface of the lock pin can be prevented from being damaged due to friction, etc.

[0037] In the inkjet printing device of the present invention, since the force applying device has the gripping portion, the bracket portion and the lock pin can be easily lifted, and thus the recording head can be easily attached and detached.

[0038] By the way, since the recording head is a precision device, a plurality of recording heads are generally densely arranged, so when installing or removing any one of the recording heads, it is possible to touch other recording heads. If it touches other recording heads, the recording head may be misaligned or cause a malfunction of the recording head. Therefore, the method of lifting the bracket part and the lock pin through the grip part is extremely effective in the installation and removal of the recording head.

[0039] In the inkjet printing device of the present invention, in addition to the coil spring, a disc spring is disposed on the lower side of the coil spring in a continuous manner as a spring portion, thereby making it easy to adjust the spring force. That is, by means of the coil spring that can fully expand and contract in the up-down direction, it is possible to ensure a sufficient amount of movement of the bracket portion in the up-down direction, and by means of the disc spring that can fully apply the (spring force), it is possible to apply a sufficient downward force to the bracket portion. It should be noted that, in the disc spring, by changing the number or type of the disc springs, it is possible to easily adjust the force.

[0040] Furthermore, by arranging the disc spring below the coil spring, the coil spring urges the bracket portion via the disc spring. This can prevent the coil spring from directly urging the bearing portion and causing the bearing portion to be displaced in the vertical direction relative to the bracket portion.

[0041] In the inkjet printing device of the present invention, by installing the force applying device on the base part positioned by abutting against the reference pin, the base part can be forced toward the row block frame at a desired position. Accordingly, the position of the base part will not be greatly misaligned, so the time required for fine-tuning the position of the base part can be greatly shortened.

[0042] In the inkjet printing device of the present invention, the first pressure pin and the first eccentric pin can easily fine-tune the position of at least the short side direction of the base part, and the second pressure pin and the second eccentric pin can easily fine-tune the position of at least the long side direction of the base part.

[0043] At this time, by controlling the force applied downward by the spring portion to be smaller than the force applied laterally by the first pressure pin or the second pressure pin to the base portion, the position of the base portion can be fine-tuned while maintaining the state in which the force applying device applies force to the base portion. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 This is a side view schematically showing an example of the inkjet printing device according to the present embodiment.

[0045] Figure 2 It is shown Figure 1 A perspective top view of a printing unit of the inkjet printing device shown.

[0046] FIG3(a) shows Figure 2 The diagram shows an enlarged plan view of a recording head unit of a printing section in a state where a biasing device is biased and a state where the biasing device is released.

[0047] FIG3(b) shows Figure 2 The figure shows an enlarged side view of a recording head unit of a printing section in a state where a biasing device is biased and a state where the biasing device is released.

[0048] Figure 4 It is an enlarged side view showing a pressure pin used for positioning in the recording head unit shown in FIG. 3( a ).

[0049] Figure 5 It is a cross-sectional view showing the first urging device in an urging state taken along line A1 - A1 of FIG. 3( a ) and in a released urging state taken along line A2 - A2 .

[0050] Figure 6 It is a cross-sectional view showing the second urging device in an urging state taken along line B1 - B1 of FIG. 3( a ) and in a released urging state taken along line B2 - B2 .

[0051] Figure 7 These are explanatory diagrams for explaining the operation of the first urging device of the recording head unit shown in FIGS. 3( a ) and 3 ( b ) during urging and releasing.

[0052] Figure 8 These are explanatory diagrams for explaining the operation of the second urging device of the recording head unit shown in FIGS. 3( a ) and 3 ( b ) during urging and releasing. DETAILED DESCRIPTION

[0053] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings as needed.

[0054] It should be noted that the same elements in the drawings are marked with the same reference numerals, and repeated descriptions are omitted.

[0055] In addition, unless otherwise specified, positional relationships such as up, down, left, and right are based on the positional relationships shown in the drawings.

[0056] Furthermore, the dimensional ratios of the drawings are not limited to the ratios shown in the drawings.

[0057] In addition, in this specification, the conveying direction of the medium to be printed is referred to as the "X direction", and the width direction of the medium to be printed is referred to as the "Y direction".

[0058] The inkjet printing device of the present invention is a device for printing by ejecting ink from a recording head onto a transported print medium.

[0059] The inkjet printing device is an on-demand type, and the ejection method can adopt a piezoelectric method, a thermal method, etc.

[0060] In addition, the printing method can be a serial method or a one-way method.

[0061] Incidentally, in the embodiment described below, a single-pass method using a line head is adopted.

[0062] In addition, the printing medium is not particularly limited, and for example, paper, film, fabric, non-woven fabric, metal foil, etc. can be used.

[0063] Ink is not particularly limited, and for example, ink containing a coloring material such as a pigment or dye or a magnetic material, an aqueous solvent, and known additives added as needed can be used.

[0064] Figure 1 It is a side view schematically showing an example of the inkjet printing apparatus 100 according to the present embodiment.

[0065] like Figure 1 As shown, the inkjet printing device 100 has: a paper supply unit 11, which is used to supply the print medium 10; a plurality of guide rollers, which are used to guide the supplied print medium 10; four printing units 12, which are used to print on the print medium 10; a drying unit 13, which is used to dry the print medium 10 after printing; and a recovery unit 14, which is used to recover the dried print medium 10.

[0066] In the inkjet printing device 100 , since the paper feeding unit 11 , the printing unit 12 , the drying unit 13 , and the collecting unit 14 are connected, the process from paper feeding of the to-be-printed medium 10 to printing, drying, and collecting can be performed in a series of processes.

[0067] It should be noted that, since the paper feeding unit 11 , the guide rollers, the drying unit 13 , and the collecting unit 14 can appropriately adopt known products, their detailed description will be omitted.

[0068] In the inkjet printing device 100 , four printing units 12 are arranged in series along the conveyance direction of the to-be-printed medium 10 .

[0069] Each printing unit 12 can independently eject ink onto the print medium 10 conveyed thereunder.

[0070] In the inkjet printing apparatus 100 , for example, full-color printing can be realized by making the printing units 12 each responsible for one different color of CMYK ink.

[0071] In the inkjet printing device 100 , the four printing units 12 have the same structure as each other.

[0072] Figure 2 It is shown Figure 1 FIG. 1 is a perspective top view of a printing unit 12 of the inkjet printing device 100. Figure 2 This is a plan view of the printing unit 12 viewed from the top plate of the head cartridge 24 .

[0073] like Figure 2As shown, the printing section 12 includes a box-shaped recording head box 24 , a line block frame 22 supported by a bottom plate portion 24 b of the recording head box 24 , and a plurality of recording head units supported by the line block frame 22 .

[0074] That is, the inkjet printing apparatus 100 includes four printing sections 12 , and the printing section 12 includes a recording head box 24 , a line block frame 22 , and a plurality of recording head units.

[0075] As described later, the recording head unit is composed of one recording head H and two urging devices 23 for urging the base 21 of the recording head H. In addition, having a plurality of recording head units means that the recording head unit is used as one unit and the unit is repeatedly provided.

[0076] In the printing unit 12 , the head box 24 is a rectangular parallelepiped box composed of an upper top plate portion (not shown), a lower bottom plate portion 24 b , and four side plates 24 a connecting the two.

[0077] Furthermore, a plurality of recording heads H (recording head units) are housed inside the recording head box 24 .

[0078] The printing unit 12 includes the recording head box 24 , so that foreign matter such as ink mist and dust from the outside can be prevented from entering the interior of the recording head box 24 and adhering to the recording head H and the like.

[0079] The head cartridge 24 may also contain a distribution ink tank (not shown) for temporarily storing ink and distributing the ink to the head body 20 of the head section H, a tube (not shown) for circulating the ink, and the like.

[0080] In the head box 24 , a row hole portion 24 c having a rectangular shape when viewed from above is formed substantially in the center of the bottom plate portion 24 b .

[0081] The row block frame 22 is attached to the bottom plate 24b so as to block the row hole 24c. That is, the row block frame 22 is supported from below by the peripheral edge of the row hole 24c of the bottom plate 24b.

[0082] As a result, the lower surface of the row block frame 22 is exposed except for the portion in contact with the bottom plate portion 24 b .

[0083] In the head box 24, pins and the like for positioning the line block frame 22 are provided on the bottom plate 24b. Specifically, the bottom plate 24b is provided with first positioning pins 24b1 and second positioning pins 24b2 at positions on both sides of the row hole 24c in the Y direction.

[0084] In addition, the second positioning pin 24b2 is attached to the direction adjusting device 25 described later.

[0085] The head box 24 can reciprocate along a rail (not shown) extending in the Y direction together with the recording heads H and the like accommodated therein.

[0086] Therefore, in the inkjet printing apparatus 100 , the recording head box 24 can be moved to a printing position for printing provided along the rails, a maintenance position for maintaining the recording head H, a storage position for storing the recording head H, and the like at an appropriate time.

[0087] It should be noted that the movement preferably uses a linear motion mechanism such as a cylinder or a ball screw.

[0088] In the printing unit 12 , the line block frame 22 is a rectangular plate-shaped frame when viewed from above, and is used to mount a plurality of recording heads H thereon.

[0089] The line block frame 22 includes: a frame body 22a; a plurality of recording head holes (not shown) provided on the frame body 22a; and a support portion 22b provided on the periphery of the recording head holes so as to protrude from the frame body 22a toward the inner side of the recording head holes.

[0090] Here, the upper surface of the support portion 22b is substantially parallel to the upper surface of the frame body 22a, and the upper surface of the support portion 22b is located below the upper surface of the frame body 22a. That is, in the row block frame 22, the frame body 22a and the support portion 22b are stepped when viewed from the side.

[0091] In the row block frame 22, a frame body portion 22a is provided with pin holes and the like for positioning with respect to the bottom plate portion 24b.

[0092] That is, the frame body 22a is provided with a positioning pin hole 22a1 at a position corresponding to the first positioning pin 24b1, and a positioning pin receiving portion 22a2 is attached to a position corresponding to the second positioning pin 24b2.

[0093] Therefore, when the row block frame 22 is mounted on the bottom plate 24b, the approximate position of the row block frame 22 relative to the bottom plate 24b can be determined by inserting the first positioning pin 24b1 into the positioning pin hole 22a1 of the row block frame 22 and fitting the second positioning pin 24b2 mounted on the direction adjustment device 25 into the positioning pin receiving portion 22a2 of the row block frame 22. As a result, the time required for fine adjustment of the position of the row block frame 22 relative to the bottom plate 24b can be greatly shortened.

[0094] The direction adjustment device 25 is Z-shaped and comprises: an adjustment body portion 25a, which is plate-shaped; a mounting portion 25b, which is arranged in a manner protruding from one end of the adjustment body portion 25a toward the row block frame 22 side; and a direction adjustment knob 25c, which is arranged at the other end of the adjustment body portion 25a in a manner protruding toward the opposite side of the row block frame 22.

[0095] Here, the second positioning pin 24 b 2 is mounted on the mounting portion 25 b , and the direction adjustment knob 25 c is supported by the side plate portion 24 a of the head cartridge 24 so as to be exposed outside the head cartridge 24 .

[0096] In addition, one end of the adjustment body 25a is rotatably attached to the upper end of a central shaft 25e extending vertically.

[0097] It should be noted that the lower end portion of the center shaft 25e is fixedly mounted to the bottom plate portion 24b.

[0098] A center positioning pin hole 25d is provided substantially at the center of the adjustment body 25a, and the position of the adjustment body 25a relative to the bottom plate 24b is determined by aligning the adjustment body 25a with the pin hole provided in the bottom plate 24b using a pin or the like.

[0099] Furthermore, in the direction adjustment device 25, by operating the direction adjustment knob 25c, the mounting portion 25b can be slightly rotated about the central axis 25e.

[0100] At this time, since the positioning pin bearing portion 22a2 of the row block frame 22 is engaged with the second positioning pin 24b2 mounted on the mounting portion 25b of the direction adjusting device 25, the positioning pin bearing portion 22a2 side of the row block frame 22 also slightly rotates together with the mounting portion 25b of the direction adjusting device 25. That is, in this case, the positioning pin bearing portion 22a2 side of the row block frame 22 slightly rotates with the first positioning pin 24b1 as the axis.

[0101] Therefore, in the printing section 12, the position of the line block frame 22 relative to the bottom plate portion 24b can be finely adjusted by the direction adjustment device 25.

[0102] In the printing unit 12, the recording head H (recording head unit) is mounted on the support portion 22b of the line block frame 22 so as to block the recording head hole. That is, the base portion 21 of the recording head H is supported from below by the support portion 22b which is the peripheral portion of the recording head hole of the line block frame 22.

[0103] As a result, the lower surface of the recording head H is exposed except for the portion abutting against the support portion 22 b of the line block frame 22 .

[0104] Here, in the line block frame 22, the recording head holes and the support parts 22b are provided at seven locations in a staggered manner when viewed from above, and the recording head H is mounted on each support part 22b.

[0105] Specifically, in the row block frame 22, the recording heads H are arranged in two columns in the X direction, one column has four recording heads H arranged side by side in the Y direction, and the other column has three recording heads H arranged side by side in the Y direction. The positions of the recording heads H in one column and the recording heads H in the other column in the X direction are different.

[0106] FIG3(a) shows Figure 2 FIG3 is an enlarged top view of a recording head unit of the printing section 12, in which the force applying device 23 applies force (the upper side of FIG3 (a) and FIG3 (b)), and in which the force is released (the lower side of FIG3 (a) and FIG3 (b)), and FIG3 (b) is an enlarged side view corresponding to FIG3 (a). It should be noted that the description of the pin used for positioning is omitted in FIG3 (b).

[0107] As shown in Fig. 3 (a) and Fig. 3 (b), the recording head unit comprises: a recording head H, which is composed of a recording head main body 20 and a plate-shaped base 21 provided on the periphery of the recording head main body 20; and a force applying device 23, which is used to install the base 21 on the line block frame 22 in a state where a force is applied to the base 21 toward the line block frame 22. That is, the printing unit 12 comprises: a plurality of recording heads H; a line block frame 22, which is used to simultaneously support the base 21 of each recording head H from below; and a force applying device 23, which is used to install each base 21 on the line block frame 22 in a state where a force is applied to the base 21 toward the line block frame 22.

[0108] It should be noted that in the printing unit 12 , the recording head body 20 of the recording head unit H and the base unit 21 are integrally formed.

[0109] In addition, the structures of the recording head sections H of the plurality of recording head units are the same as each other.

[0110] Right now, Figure 2 The structures of the seven recording headers H shown are identical to each other.

[0111] In the recording head unit, the position of the base portion 21 of the recording head H relative to the line block frame 22 is determined by the reference pin 41 , the pressure pin 42 , and the eccentric pin 43 attached to the support portion 22 b of the line block frame 22 .

[0112] Here, the reference pin 41 is a normal pin; the eccentric pin 43 is rotatable and is a pin having the center of the pin at an eccentric position relative to the rotation center; and the pressure pin 42 is a pin that can apply a spring force in the lateral direction.

[0113] It should be noted that the eccentric pin 43 is also referred to as a first eccentric pin 43 or a second eccentric pin 43 as needed. Similarly, the pressure pin 42 is also referred to as a first pressure pin 42 or a second pressure pin 42.

[0114] Figure 4 It is an enlarged side view showing a pressure pin used for positioning in the recording head unit shown in FIG. 3( a ).

[0115] like Figure 4 As shown, the pressure pin 42 for positioning the base portion 21 is composed of a head portion 42a and a body portion 42b.

[0116] In the pressure pin 42 , a coil spring is built in the body portion 42 b , and when the head portion 42 a is pressed in the lateral direction by the base portion 21 , stress is generated by the spring force of the coil spring.

[0117] At this time, in the pressure pin 42, since the head 42a is egg-shaped, the stress generated in the arc direction centered on the lower end of the head 42a can apply a force sufficient to apply force to the base 21 downward in addition to the force in the direction toward the base 21.

[0118] Returning to Figure 3(a), on the supporting portion 22b of the row block frame 22, a reference pin 41 and a first eccentric pin 43 are installed at a certain distance from each other at a position where they can abut against one long side of the base portion 21, and two first pressure pins 42 are installed at a certain distance from each other at a position where they can abut against the other long side.

[0119] It should be noted that the reference pin 41 and the one first pressure pin 42 , and the first eccentric pin 43 and the other first pressure pin 42 are disposed at opposing positions across the base portion 21 .

[0120] Therefore, on the base portion 21, the first pressure pin 42 applies force to the base portion 21 in the X direction (short side direction) to rotate the first eccentric pin 43, thereby enabling fine adjustment of the position of the base portion 21 in the rotation direction centered on the reference pin 41 on the XY plane, i.e., at least the position of the base portion 21 in the short side direction.

[0121] Furthermore, the second eccentric pin 43 is mounted on the support portion 22 b of the row block frame 22 at a position capable of contacting one short side surface of the base portion 21 , and the second pressure pin 42 is mounted at a position capable of contacting the other short side surface.

[0122] Therefore, in the base portion 21 , the second pressure pin applies force to the base portion 21 in the Y direction (longitudinal direction) to rotate the second eccentric pin 43 , thereby making it possible to finely adjust at least the longitudinal position of the base portion 21 .

[0123] It should be noted that, regarding the fine adjustment of the position of the base portion 21, the first eccentric pin 43 is first rotated to finely adjust the position of the base portion 21 in the short side direction. At this time, since the position of the base portion 21 in the long side direction will also be misaligned, it is preferred to then rotate the second eccentric pin 43 to finely adjust the position of the base portion 21 in the long side direction.

[0124] In addition, a stopper 44 for suppressing the rotation of the eccentric pin 43 is attached to the row block frame 22 , for example, next to the eccentric pin 43 .

[0125] By tightening the locking screw, the stopper 44 presses the upper surface of the eccentric pin 43 from above.

[0126] According to this, for example, after the position fine adjustment by the eccentric pin 43 is completed, it is possible to prevent the eccentric pin 43 from accidentally rotating.

[0127] The recording head H is preferably mounted on the line block frame 22 by the force applying device 23 in a state where the position of the base 21 relative to the line block frame 22 is determined to a certain extent. In this way, the position of the base 21 will not be greatly displaced, so the time required for fine adjustment of the position of the recording head H can be greatly shortened.

[0128] In addition, the force of the spring portion 32 of the urging device 23 described later that urges the base portion 21 downward is preferably smaller than the force of the pressure pin 42 that urges the base portion 21 laterally. In this case, the lateral position of the base portion 21 can be finely adjusted while the urging device 23 urges the base portion 21.

[0129] Back to Figure 2 3(a) and 3(b), in the recording head H, the recording head body 20 is substantially in the shape of a rectangular parallelepiped, and is used to temporarily store ink and eject the ink.

[0130] In the recording head main body 20 , a plurality of nozzles are formed on the lower surface, and ink supplied to the inside can be ejected from the nozzles.

[0131] The nozzles formed on the lower surface of the head body 20 are exposed through the head holes of the line block frame 22 and the line holes 24 c of the head box. Therefore, the head body 20 can eject ink onto the print medium 10 conveyed below the printing unit 12 .

[0132] In the recording head unit, the force applying device 23 is a device for installing the base portion 21 to the line block frame 22 while pressing the base portion 21 to the line block frame 22. It should be noted that in the recording head unit, after the recording head H is installed to the line block frame 22 by the force applying device 23, the force applied by the force applying device 23 is still maintained.

[0133] On the other hand, the urging device 23 can also forcibly release its urging force. Thus, the recording head H can be easily removed.

[0134] Two biasing devices 23 are provided for each base portion 21 .

[0135] Specifically, the urging devices 23 are disposed at positions that are diagonal to the base portion 21. Thus, the urging devices 23 can urge the base portion 21 downward with as uniform a force as possible over the entire base portion 21.

[0136] It should be noted that the two urging devices 23 have the same structure except that the shapes of the bracket parts 31 are different.

[0137] For convenience of explanation, the force applying device 23 having the bracket portion 31 in an L-shape when viewed from above (the force applying device on the upper right of the recording head unit shown in FIG. 3(a)) is referred to as the "first force applying device 23", and the force applying device 23 having the bracket portion 31 in a rectangular shape when viewed from above (the force applying device on the lower left of the recording head unit shown in FIG. 3(a)) is referred to as the "second force applying device 23". It should be noted that when only the force applying device 23 is referred to, both the first force applying device 23 and the second force applying device 23 are referred to.

[0138] Figure 5 3 (a) along the A1-A1 line in the state of applying force, the first force applying device ( Figure 5 ), and the first force applying device ( Figure 5 sectional view of the right side of the image.

[0139] Figure 6 3 (a) along the B1-B1 line in the state of the second force applying device ( Figure 6 ), and the second force applying device ( Figure 6 on the right side of the screen).

[0140] like Figure 5 and Figure 6 As shown, the force-applying device 23 includes: a shaft portion 30, which is mounted on the frame body portion 22a of the row block frame 22 and extends in the up-down direction; a bracket portion 31, which is mounted on the shaft portion 30 via a bearing portion 30a1 in a manner that it can move up and down along the shaft portion 30; a spring portion 32, which is mounted on the shaft portion 30 and is used to apply force to the bracket portion 31 downward; a holding portion 34, which is mounted on the bracket portion 31 and protrudes upward from the bracket portion 31; a locking pin 33, which is mounted on the bracket portion 31 and protrudes downward from the bracket portion 31; and a block portion 35, which is provided on the bracket portion 31 and protrudes downward from the bracket portion 31.

[0141] In the urging device 23, the shaft portion 30 includes: a small diameter shaft portion 30a extending in the vertical direction and having a cylindrical shape; and a large diameter shaft portion 30b provided on the upper portion of the small diameter shaft portion 30a and having a larger diameter than the small diameter shaft portion 30a.

[0142] In the shaft portion 30 , the lower end portion of the small-diameter shaft portion 30 a is a threaded portion that is threadedly engaged with a threaded hole provided in the frame body portion 22 a of the row block frame 22 .

[0143] Furthermore, a bearing portion 30a1 (self-lubricating bushing) is attached to the lower portion of the small-diameter shaft portion 30a, and the bracket portion 31 is attached via the bearing portion 30a1.

[0144] In addition, a spring portion 32 is attached to the middle portion of the small-diameter shaft portion 30 a so as to surround the middle portion, and the spring portion 32 is sandwiched between the large-diameter shaft portion 30 b and the bracket 31 .

[0145] In the first force applying device 23, the bracket portion 31 has a surface extending in the horizontal direction and is an L-shaped plate when viewed from above. In the second force applying device 23, the bracket portion 31 has a surface extending in the horizontal direction and is a rectangular plate when viewed from above.

[0146] Furthermore, the urging device 23 is provided with a gripping portion 34 , a lock pin 33 , and a block portion 35 .

[0147] That is, the bracket portion 31 is integrated with the bearing portion 30 a 1 , the grip portion 34 , the lock pin 33 , and the block portion 35 .

[0148] The bracket portion 31 is integrated with the above-mentioned components, and can move up and down along the longitudinal direction of the shaft portion 30 (small diameter shaft portion 30a), and can rotate around the shaft portion 30 (small diameter shaft portion 30a).

[0149] At this time, since the bracket portion 31 is attached to the small-diameter shaft portion 30 a of the shaft portion 30 via the bearing portion 30 a 1 , the bracket portion 31 can smoothly move up and down and rotate.

[0150] In the urging device 23, as described above, the small diameter shaft portion 30a is inserted through the spring portion 32, and the spring portion 32 is sandwiched between the large diameter shaft portion 30b and the bracket portion 31. Therefore, the spring portion 32 can expand and contract by the length of the small diameter shaft portion 30a.

[0151] Furthermore, since the spring portion is held between the large diameter shaft portion 30 b and the bracket portion 31 in a shortened state, a downward spring force (biasing force) can be constantly applied to the bracket portion 31 starting from the large diameter shaft portion 30 b .

[0152] Here, as the spring portion 32 , a coil spring (a coil-shaped compression spring), a leaf spring, a disc spring, or the like can be used.

[0153] Among the above-mentioned various springs, it is preferable that the spring portion 32 adopts a coil spring or a disc spring, and it is more preferable that a coil spring and a disc spring are adopted.

[0154] More specifically, it is more preferable that the spring portion 32 is composed of a coil spring 32 a and a disc spring 32 b disposed on the lower side of the coil spring 32 a so as to be continuous with the coil spring 32 a .

[0155] In this case, the spring force of the spring portion 32 can be easily adjusted.

[0156] Furthermore, by arranging the disc spring 32b below the coil spring 32a, the coil spring 32a urges the bracket portion 31 via the disc spring 32b, thereby preventing the coil spring 32a from directly urging the bearing portion 30a1 and causing the bearing portion 30a1 to be displaced in the vertical direction relative to the bracket portion 31.

[0157] In the force applying device 23 , the lock pin 33 is cylindrical, and the upper end portion thereof is fixed to the bracket portion 31 by a fastener such as a bolt.

[0158] The lower end of the lock pin 33 is flat and is disposed at a force application position 21 a on the base portion 21 when force is applied, and is disposed at a standby position 22 c on the row block frame 22 when force is released.

[0159] Here, the standby position 22 c is provided in the row block frame 22 (see FIGS. 3( a ) and 3 ( b )), and is a stopper hole provided on the upper surface side of the row block frame 22 .

[0160] At the standby position 22c, the upper end surface 22c1 of the stopper hole is located above the lower end surface 33a of the lock pin 33 when the lock pin 33 is arranged at the standby position 22c.

[0161] According to this, the lock pin 33 disposed at the standby position 22 c abuts against the wall around the stopper hole, thereby preventing the bracket portion 31 from rotating unexpectedly.

[0162] In the force applying device 23, the gripping portion 34 is cylindrical and is disposed between the shaft portion 30 and the lock pin 33, and its lower end is a threaded portion that is threadedly engaged with a threaded hole provided in the bracket portion 31. Therefore, by lifting the gripping portion 34, the gripping portion 34, the bracket portion 31, the bearing portion 30a1, the lock pin 33 and the block portion 35 can be lifted integrally.

[0163] The gripping portion 34 is provided so as to protrude upward from the bracket portion 31 , and its upper end portion is located above the large-diameter shaft portion 30 b . Therefore, the gripping portion 34 can be easily gripped by the urging device 23 .

[0164] In the urging device 23 , since the holder 34 can easily lift the bracket 31 and the lock pin 33 , the bracket 31 can be easily moved up and down relative to the shaft 30 and can be easily rotated about the shaft 30 .

[0165] In the force applying device 23 , the block portion 35 and the bracket portion 31 are formed integrally.

[0166] The block portion 35 is block-shaped and is disposed on the upper surface of the frame body portion 22 a when the lock pin 33 is disposed at the standby position 22 c . Thus, the entire urging device 23 is supported by the block portion 35 .

[0167] At this time, it is preferred that the lower surface of the lock pin 33 does not contact the bottom surface of the stopper hole at the standby position 22c, but is in a floating state with a certain distance therefrom. This can prevent the lower surface of the lock pin 33 from being damaged by friction or the like.

[0168] Figure 7 3 (a) and 3 (b) when the first force applying means of the recording head unit applies force ( Figure 7 left side) and when the force is released ( Figure 7 The diagram of the action of Figure 8 3 (a) and 3 (b) when the second force applying means of the recording head unit applies force ( Figure 8 left side) and when the force is released ( Figure 8 ) is an illustration of the action.

[0169] like Figure 7 and Figure 8 As shown, when applying force, the lock pin 33 of the force applying device 23 is disposed at the force applying position 21 a on the base portion 21 .

[0170] At this time, since the bracket portion 31 is urged downward by the spring portion 32 , the base portion 21 is urged downward, that is, toward the support portion 22 b side of the block frame 22 via the lock pin 33 .

[0171] That is, in the inkjet printing apparatus 100 , the lock pin 33 of the urging device 23 is arranged on the upper surface of the base portion 21 of the recording head H, thereby urging the recording head H downward.

[0172] By lifting the gripping portion 34 of the urging device 23 upward from this state, the bracket portion 31 moves upward along the shaft portion 30 and the lock pin 33 is also lifted simultaneously. Thus, the urging is released.

[0173] That is, in the inkjet printing device 100 , the urging device 23 is released by lifting the lock pin 33 .

[0174] Note that, in this case, since the downward biasing force from the spring portion 32 is applied to the bracket portion 31 , the bracket portion 31 is forcibly lifted up by a force exceeding the biasing force.

[0175] Next, by rotating the grip portion 34 of the urging device 23 , the bracket portion 31 is rotated about the shaft portion 30 , and the lock pin 33 is also rotated simultaneously.

[0176] The lock pin 33 performs this rotational movement from a position above the force application position 21 a to a position above the standby position 22 c .

[0177] Then, by lowering the grip 34 of the urging device 23 downward, the bracket 31 moves downward along the shaft 30, and the lock pin 33 is arranged at the standby position 22c. As described above, the lock pin 33 does not contact the stopper hole, that is, the bottom surface of the standby position 22c.

[0178] At this time, the block portion 35 provided in the bracket portion 31 is arranged on the upper surface of the frame body portion 22a of the row block frame 22. Accordingly, the urging device 23 is in a state of being supported by the frame body portion 22a.

[0179] It should be noted that, when the lock pin 33 is moved from the standby position 22 c to the force application position 21 a , the reverse operation of the above operation may be performed.

[0180] In this way, in the inkjet printing apparatus 100 , the recording head H can be easily attached and detached simply by moving the lock pin 33 up and down via the holder portion 31 .

[0181] Furthermore, since the force applied to the holder portion 31 comes from the spring portion 32 , the same force is applied to the base portion 21 every time the recording head portion H is mounted.

[0182] Therefore, every time the recording head H is mounted, the occurrence of variations in the printing accuracy of the recording head H can be suppressed as much as possible.

[0183] Furthermore, since the lock pin 33 can be retracted to the horizontal standby position 22 c by rotating the holder portion 31 around the shaft portion 30 , the recording head H can be attached and detached more easily.

[0184] As mentioned above, although embodiment of this invention is described, this invention is not limited to the said embodiment.

[0185] The inkjet printing apparatus 100 of the present embodiment includes the paper feeding section 11 , the printing section 12 , the drying section 13 , and the collecting section 14 . However, the paper feeding section 11 , the drying section 13 , and the collecting section 14 may be provided independently.

[0186] In the inkjet printing apparatus 100 of the present embodiment, one line block frame 22 on which the recording head H is mounted is mounted on the bottom plate portion 24 b of the head cartridge 24 , but a plurality of line block frames on which the recording head H is mounted may be mounted.

[0187] In the inkjet printing apparatus 100 of this embodiment, the recording heads H are mounted at seven locations on the line block frame 22 in a staggered pattern when viewed from above, but the number of the recording heads H and the locations where the recording heads H are mounted are not limited thereto.

[0188] In the inkjet printing apparatus 100 of this embodiment, positioning pins, the direction adjusting device 25 and the like are used to determine the position of the line block frame 22 relative to the bottom plate 24 b of the head box 24 , but the positioning method is not limited thereto.

[0189] Similarly, when determining the position of the base portion 21 relative to the row block frame 22, reference pins 41, pressure pins 42, eccentric pins 43, etc. are used, but the positioning method is not limited to this.

[0190] In the recording head unit of the inkjet printing device 100 of the present embodiment, two urging devices 23 are provided for each base portion 21 , but the present invention is not limited thereto, and one, or three or more urging devices 23 may be provided.

[0191] Furthermore, the position where the urging device 23 is provided is not limited to the position that is the diagonal position of the base portion 21 .

[0192] In the inkjet printing device 100 of this embodiment, when the lock pin 33 is arranged on the base portion 21 to apply force, a space is formed between the side surface of the block portion 35 and the side surface of the frame body portion 22a of the row block frame 22, but the two may contact each other. In this case, the contact between the two can also be used to position the force applying device 23 at the force applying position 21a.

[0193] In the urging device 23 of the inkjet printing device 100 of this embodiment, the lower end of the shaft portion 30 is a threaded portion that is threadedly engaged with a threaded hole provided in the frame body portion 22a of the line block frame 22, but the mounting method is not limited thereto.

[0194] Similarly, the lower end of the grip portion 34 is a threaded portion that is threadedly engaged with a threaded hole provided in the bracket portion 31 , but the mounting method is not limited thereto.

[0195] In the urging device 23 of the inkjet printing apparatus 100 of the present embodiment, the block portion 35 is formed integrally with the holder portion 31 , but may be provided independently.

[0196] In addition, the upper end portion of the lock pin 33 is fixed to the bracket portion 31 by a fastener such as a bolt, but the mounting method is not limited thereto.

[0197] In addition, the lock pin 33 and the gripping portion 34 are both cylindrical, but are not limited thereto and may be polygonal or the like.

[0198] Industrial Applicability

[0199] The inkjet printing device of the present invention can be used as a device for forming a pattern or the like by applying ink to a printing medium.

[0200] The inkjet printing device of the present invention can easily detach and remove the recording head, and can minimize the deviation in printing accuracy each time the recording head is installed.

[0201] Description of Reference Numerals

[0202] 10: Printing medium

[0203] 100: Inkjet printing device

[0204] 11: Paper supply unit

[0205] 12: Printing Department

[0206] 13: Drying section

[0207] 14: Recycling Department

[0208] 20: Recording head main body

[0209] 21: Base

[0210] 21a: Force application position

[0211] 22: Line Block Frame

[0212] 22a: Main frame

[0213] 22a1: Dowel pin hole

[0214] 22a2: Positioning pin bearing part

[0215] 22b: Supporting part

[0216] 22c: Standby position

[0217] 22c1: Upper end surface of stop hole

[0218] 23: Force applying device

[0219] 24: Recording head box

[0220] 24a: Side panel

[0221] 24b: Bottom plate

[0222] 24b1: 1st positioning pin

[0223] 24b2: 2nd positioning pin

[0224] 24c: hole section

[0225] 25: Direction adjustment device

[0226] 25a: Adjust the main body

[0227] 25b: Installation

[0228] 25c: Direction adjustment knob

[0229] 25d: Center positioning pin hole

[0230] 25e: Central axis

[0231] 30: Axis

[0232] 30a: Small diameter shaft

[0233] 30b: Large diameter shaft

[0234] 30a1: Bearing

[0235] 31: Bracket

[0236] 32: Spring

[0237] 32a: Coil spring

[0238] 32b: Disc spring

[0239] 33: Locking pin

[0240] 33a: Lower end surface of the lock pin

[0241] 34: Grip

[0242] 35: Block

[0243] 41: Reference pin

[0244] 42: Pressure pin

[0245] 42a: Head

[0246] 42b: Trunk

[0247] 43: Eccentric pin

[0248] 44: Block

[0249] H: Record the head.

Claims

1. An inkjet printing device having a printing unit capable of ejecting ink, characterized in that: The printing unit has: A plurality of recording heads, each of which is composed of a recording head body and a base portion disposed on a periphery of the recording head body; A row block frame, the row block frame is used to support the base portion from below; as well as a force applying device for installing the base portion on the row block frame while applying force to the base portion toward the row block frame side, The force applying device comprises: A shaft portion, the shaft portion is mounted on the row block frame and extends in the up-down direction; a bracket portion, the bracket portion being mounted on the shaft portion via a bearing portion in a manner that the bracket portion can move up and down along the shaft portion; a spring portion, the spring portion being mounted on the shaft portion and being used to apply force downward to the bracket portion; as well as a lock pin, the lock pin being mounted on the bracket portion and protruding downward from the bracket portion, When force is applied, the locking pin is disposed on the upper surface of the base portion. When the force is released, the lock pin is lifted upward.

2. The inkjet printing device according to claim 1, wherein: The force applying device further comprises a gripping portion, which is mounted on the bracket portion and protrudes upward from the bracket portion. By lifting the holding portion, the holding portion, the bracket portion, and the lock pin are lifted integrally.

3. The inkjet printing device according to claim 1, wherein: The bracket is mounted on the shaft via a bearing so as to be movable up and down along the shaft and to be rotatable around the shaft. When force is applied, the locking pin is disposed on the upper surface of the base portion. When the force is released, the lock pin is lifted upward, and the bracket portion is rotated to arrange the lock pin at a standby position provided on the upper surface of the row block frame.

4. The inkjet printing device according to claim 3, wherein: The standby position is a stopper hole provided on the upper surface side of the row block frame. An upper end surface of the stop hole is located above a lower end surface of the lock pin when the lock pin is arranged at the standby position.

5. The inkjet printing device according to claim 3, wherein: The force applying device further comprises a block portion, which is arranged on the bracket portion and protrudes downward from the bracket portion. When the lock pin is arranged at the standby position, the block portion is arranged on the upper surface of the row block frame.

6. The inkjet printing device according to claim 1, wherein: The shaft portion comprises a small diameter shaft portion and a large diameter shaft portion, wherein the small diameter shaft portion is cylindrical, and the large diameter shaft portion is arranged on the upper portion of the small diameter shaft portion and has a larger diameter than the small diameter shaft portion. The small diameter shaft portion is inserted through the spring portion, and the spring portion is clamped between the large diameter shaft portion and the bracket portion. The spring portion is composed of a coil spring and a disc spring, and the disc spring is disposed on a lower side of the coil spring so as to be continuous with the coil spring.

7. The inkjet printing device according to claim 1, wherein: The base portion is positioned by abutting against a reference pin provided on the row block frame. In the positioned state, the force applying device is installed.

8. The inkjet printing device according to claim 1, wherein: The base portion is rectangular when viewed from above. The row block frame is provided with a first eccentric pin at a position capable of abutting against a long side surface of the base portion, a first pressure pin at a position capable of abutting against another long side surface, a second eccentric pin at a position capable of abutting against a short side surface, and a second pressure pin at a position capable of abutting against another short side surface. The first pressure pin applies force to the base portion in the short side direction. The second pressure pin applies force to the base portion in the longitudinal direction. By rotating the first eccentric pin and / or the second eccentric pin, the position of the base portion is finely adjusted.

9. The inkjet printing device according to claim 8, wherein: The force applied downward to the base portion by the spring portion is smaller than the force applied laterally to the base portion by the first pressure pin or the second pressure pin.

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