JP7010150B2 - Liquid discharge unit and liquid discharge device - Google Patents

Description

The present invention relates to a liquid discharge unit and a liquid discharge device.

A liquid ejection recording type image forming apparatus (inkprint) that uses, for example, a liquid ejection head (droplet ejection head) for ejecting droplets as an image forming apparatus such as a printer, a facsimile, a copying apparatus, a plotter, or a multifunction device thereof. Recording devices, etc.) are known.

When forming an image in a liquid ejection recording type image forming apparatus, the impact accuracy of the droplets ejected from the nozzle greatly affects the image quality. If the landing accuracy of the droplet is poor, the image quality will deteriorate, so it is necessary to position the recording head with high accuracy. Therefore, a configuration in which the base plate holding the recording head is fixed to the carriage side plate by using an L-shaped block having an elongated hole has been used for a long time.

Further, Patent Document 1 describes a sub-carriage having a recording head, a recording head surface parallelism adjusting unit (such as an eccentric cam 24) for adjusting the swing position of the sub-carriage, and a recording head surface parallelism adjusting unit for the sub-carriage. A carriage provided with a sub-carriage urging means (such as a torsion spring 13) for urging the carriage is disclosed.

By adjusting the parallelism of the sub-carriage, this carriage can adjust the parallelism of the recording head around the axis parallel to the main scanning direction.

However, in the conventional carriage configuration, if the carriage is accidentally moved down while the thick media (recording medium) is on the table, the base plate and the media collide with each other and the base plate shifts. was there. In addition, there is a problem that the base plate moves due to the vibration generated during transportation, and the parallelism with the table is deviated.

In particular, in the carriage of Patent Document 1, since the vibration or impact of the plate acts directly on the eccentric cam, the rotation angle tends to shift, and therefore the plate position may easily fluctuate.

Therefore, an object of the present invention is to provide a liquid discharge unit including a liquid discharge head and a carriage, which can absorb shocks and vibrations and maintain a liquid discharge head surface at a predetermined position.

The above-mentioned problems are a liquid discharge head having a plurality of nozzles for discharging droplets, a base plate holding one or a plurality of the liquid discharge heads, a plurality of carriage side plates holding the base plate, the base plate and the plurality. In a liquid discharge unit provided with at least one position adjusting means provided between the carriage side plates, the position adjusting means includes a through hole, and a position adjusting bracket provided on the carriage side plate and the through hole. And the adjusting screw that is inserted through the base plate and adjusts the separation distance between the position adjusting bracket and the base plate, and is interposed between the position adjusting bracket and the base plate, and the base plate is placed in the position adjusting bracket. It is solved by a liquid discharge unit characterized by having an elastic member urging in a direction away from the liquid.

In the liquid discharge unit of the present invention, the elastic member interposed between the position adjusting bracket and the base plate absorbs the impact and vibration applied to the base plate and urges the base plate in a direction away from the position adjusting bracket. The liquid discharge head surface can be maintained in a predetermined position.

It is a perspective view which shows the whole structure of the liquid discharge apparatus which concerns on one Embodiment of this invention. It is a perspective view which shows the carriage scanning mechanism part which concerns on one Embodiment of this invention. It is a schematic front view which shows the carriage which concerns on one Embodiment of this invention. FIG. 3 is a schematic front view showing one end of the carriage shown in FIG. It is a schematic front view which shows the carriage (the 1) which concerns on another embodiment of this invention. It is a schematic front view which shows the carriage (the 2) which concerns on another embodiment of this invention.

(Embodiment)
FIG. 1 is a perspective view showing an overall configuration of a liquid discharge device according to an embodiment of the present invention, and FIG. 2 is a perspective view showing a carriage scanning mechanism unit according to an embodiment of the present invention.

As shown in FIG. 1, this liquid ejection device is a serial type inkjet recording device, and includes a device main body 1 and a support base 2 for supporting the device main body 1. Inside the apparatus main body 1, guide rods 3 and guide stays 4, which are guide members, are hung on both side plates, and the carriage 5 moves in the arrow A direction (main scanning direction) to these guide rods 3 and guide stays 4. It is supported as much as possible.

The carriage 5 is equipped with a recording head 6 including a liquid ejection head that ejects ink droplets of each color of black (K), yellow (Y), magenta (M), and cyan (C). Each recording head 6 includes a plurality of nozzles for ejecting droplets. Further, each recording head 6 integrally includes a head tank that supplies ink to each recording head 6.

The main scanning mechanism unit 10 that moves and scans the carriage 5 is arranged on one side of the main scanning direction, a drive motor 11 that is rotationally driven by the drive motor 11, and the other side of the main scanning direction. The driven pulley 13 is provided with a timing belt 14 which is a traction member hung between the driven pulley 12 and the driven pulley 13. The driven pulley 13 is tensioned outward (in a direction away from the drive pulley 12) by a tension spring.

In the recording area of the main scanning area of the carriage 5, the paper 20 is intermittently conveyed by the suction transport unit in the arrow B direction (sub-scanning direction, paper transport direction) orthogonal to the main scanning direction of the carriage 5.

Further, a maintenance / recovery device 8 for maintaining / recovering the recording head 6 is arranged in one end side region of the main scanning region. Further, outside the carriage moving region in the main scanning direction, or in the other end side region of the main scanning region, a main cartridge 9 containing inks of each color supplied to the sub tank of the recording head 6 is attached to the apparatus main body 1. It can be attached and detached freely. Further, although roll paper (hereinafter referred to as “paper 20”) is set in the paper feed means 21, roll paper having different sizes in the width direction can also be set.

In the liquid discharge device configured as described above, image formation is performed as follows. First, the paper 20 conveyed from the paper feeding means 21 is conveyed to the recording area by the conveying means from the rear to the front of the apparatus main body 1. Next, the carriage 5 is moved in the main scanning direction, and the recording head 6 is driven according to the image information to eject the droplets while intermittently feeding the paper 20 to the platen 7 at the suction transfer unit. The required image is formed on the paper 20. Then, the paper 20 after image formation is cut to a predetermined length and discharged to a paper ejection tray arranged on the front side of the apparatus main body 1.

Here, the configuration in which the paper 20 is cut and discharged is described, but it is also possible to wind the paper after image formation at the paper ejection portion without cutting.

Next, the configuration of the carriage (liquid discharge unit) including the recording head, which is a feature of the present invention, will be described in detail.

FIG. 3 is a schematic front view showing a carriage according to an embodiment of the present invention, and FIG. 4 is a schematic front view showing one end of the carriage shown in FIG. As shown in FIG. 3, the base plate 22 of the carriage 5 holds recording heads 6a, 6b, 6c arranged in a staggered manner in the X direction (sub-scanning direction). When the recording heads are not individually distinguished, they are referred to as "recording head 6". Further, the number of recording heads 6 mounted on the base plate 22 may be one, two, or more than three.

The base plate 22 is held by a plurality of carriage side plates 23, but in the present embodiment, the position adjusting means 27 is provided between the base plate 22 and the carriage side plates 23. As shown in FIG. 4, the position adjusting means 27 is provided on the carriage side plate 23, and has a position adjusting bracket 24 having a through hole 24a, an adjusting screw 25 inserted through the through hole 24a and the base plate 22, and an adjusting screw 25. A compression spring 26 inserted into the shaft of the carriage is provided.

The position adjusting bracket 24 is integrally formed with the carriage side plate 23, but may be separately attached. Further, the diameter of the through hole 24a is larger than the shaft portion (outer diameter) of the adjusting screw 25 and smaller than the head bearing surface.

The adjusting screw 25 has a shape in which the head bearing surface abuts on the position adjusting bracket 24 when inserted into the through hole 24a. Further, the base plate 22 is formed with a female threaded portion 22b into which the male threaded portion of the adjusting screw 25 is screwed.

The compression spring 26 is interposed between the position adjusting bracket 24 and the base plate 22 and is provided around the axis of the adjusting screw 25. Therefore, the compression spring 26 urges the base plate 22 in a direction (−Z direction) away from the position adjusting bracket 24. The compression spring 26 is an example of an elastic member, and a coil spring or a rubber spring may be used instead.

Since the carriage 5 of the present embodiment is configured in this way, the position of the base plate 22 (that is, the separation distance between the position adjusting bracket 24 and the base plate 22) can be adjusted by the screw tightening amount of the adjusting screw 25. Further, by providing the position adjusting means 27 on the carriage side plates 23 at both ends of the base plate 22 in the Y direction as shown in FIG. 3, the position and posture (parallelism) of the base plate 22 can be easily adjusted.

Further, even if the base plate 22 collides with the medium (recording medium) below the base plate 22, the compression spring 26 absorbs the impact and the residual vibration and urges the base plate 22 downward (−Z direction) again. Therefore, the base plate 22 whose position has changed can be positioned at the adjusted predetermined position. Furthermore, even if the base plate 22 vibrates due to vibration generated during transportation, for example, the compression spring 26 absorbs the vibration and can be positioned in the same manner.

Here, the carriage 5 of the present embodiment and the carriage described in Patent Document 1 will be compared. The carriage of Patent Document 1 is similar to the present embodiment in that the plate for holding the head can be adjusted and the carriage has an urging means (torsion spring) for urging the plate. However, the present embodiment uses the adjusting screw 25, whereas Patent Document 1 uses an eccentric cam.

In the carriage of Patent Document 1, since the vibration or impact of the plate directly acts on the eccentric cam, the rotation angle of the eccentric cam tends to deviate. Also, in the eccentric cam, the deviation of the rotation angle gives the plate a not-so-small displacement. Therefore, in the carriage of Patent Document 1, the plate position may fluctuate due to vibration or impact.

On the other hand, in the carriage 5 of the present embodiment, first, the separation distance between the position adjusting bracket 24 and the base plate 22 is kept constant by the adjusting screw 25. Then, even if it fluctuates due to vibration or impact by the compression spring 26, it is positioned at the adjusted position again. Therefore, the carriage 5 of the present embodiment is more advantageous than the carriage of Patent Document 1 because it can absorb vibration or impact and maintain the position (recording head surface) of the base plate 22 at a predetermined position.

Subsequently, another embodiment of the present invention and an advantageous configuration will be described.

FIG. 5 is a schematic front view showing a carriage (No. 1) according to another embodiment of the present invention. In FIG. 5, the same objects as those in FIGS. 3 and 4 are designated by the same reference numerals, and detailed description thereof will be omitted.

When the base plate 22 is fixed by the position adjusting means 27 (adjusting screws 25) at two or more places, the base plate 22 may be tilted and fixed due to the distortion at the time of mounting the carriage side plate 23 and the processing accuracy of the base plate 22. be. Therefore, in the present embodiment, at least one of the position adjusting brackets 28 has a convex (dome-shaped curved surface) seating surface, and the head seating surface of the adjusting screw 25 is brought into contact with the seating surface. Since the convex seat surface corresponds to the inclination, the inclination of the base plate 22 can be avoided.

FIG. 6 is a schematic front view showing a carriage (No. 2) according to another embodiment of the present invention. In FIG. 6, the same objects as those in FIGS. 3 and 4 are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 6, the base plate 29 of the present embodiment has a curved surface shape at least one end facing the carriage side plate 23. This makes it possible to prevent the base plate 29 from tilting when the adjusting screw 25 is tightened due to distortion during assembly of the carriage side plate 23 and processing accuracy of the base plate 29.

Subsequently, a clear definition is given for the terms used in the present application.

The "liquid discharge device" is a device including a liquid discharge head or a liquid discharge unit, which drives the liquid discharge head to discharge the liquid. The device for discharging the liquid includes not only a device capable of discharging the liquid to a device to which the liquid can adhere, but also a device for discharging the liquid into the air or into the liquid.

This "liquid discharge device" can also include means related to feeding, transporting, and discharging paper to which a liquid can adhere, as well as a pretreatment device, a posttreatment device, and the like.

The "liquid ejection device" includes, for example, an image forming apparatus that ejects ink to form an image on paper, and a layered powder for forming a three-dimensional object (three-dimensional object). There is a three-dimensional modeling device (three-dimensional modeling device) that discharges the modeling liquid into the powder layer.

Further, the "liquid discharge device" is not limited to a device in which a significant image such as a character or a figure is visualized by the discharged liquid. For example, those that form patterns that have no meaning in themselves and those that form a three-dimensional image are also included.

The above-mentioned "thing to which a liquid can adhere" means a material to which a liquid can adhere at least temporarily, such as a material to which the liquid adheres and adheres, and a material to which the liquid adheres and permeates. Specific examples include paper, recording paper, recording paper, film, recorded media such as cloth, electronic substrates, electronic components such as piezoelectric elements, powder layers (powder layers), organ models, and media such as inspection cells. Yes, and includes everything to which the liquid adheres, unless otherwise specified.

The above "materials to which liquid can adhere" are temporary liquids such as paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, ceramics, building materials such as wallpaper and flooring, and textiles for clothing. But it is good if it can be attached.

The "liquid" may have a viscosity and surface tension that can be discharged from the head, and is not particularly limited, but has a viscosity of 30 mPa · s or less at room temperature, under normal pressure, or by heating or cooling. It is preferable to have. More specifically, solvents such as water and organic solvents, colorants such as dyes and pigments, functionalizing materials such as polymerizable compounds, resins and surfactants, biocompatible materials such as DNA, amino acids and proteins, and calcium. , Solutions, suspensions, emulsions and the like containing edible materials such as natural pigments. These can be used, for example, in inks for inkjet, surface treatment liquids, liquids for forming electronic elements and light emitting elements, liquids for forming electronic circuit resist patterns, and liquids for three-dimensional modeling.

Further, the "liquid discharge device" includes, but is not limited to, a device in which the liquid discharge head and the device to which the liquid can adhere move relatively. Specific examples include a serial type device that moves the liquid discharge head, a line type device that does not move the liquid discharge head, and the like.

In addition, as the "liquid ejection device", there is a processing liquid applying device that ejects the processing liquid onto the paper in order to apply the processing liquid to the surface of the paper for the purpose of modifying the surface of the paper. Further, there is also an injection granulation device for granulating fine particles of a raw material by injecting a composition liquid in which a raw material is dispersed in a solution through a nozzle.

The "liquid discharge unit" is a liquid discharge head integrated with functional parts and a mechanism, and is a collection of parts related to liquid discharge. For example, the "liquid discharge unit" includes a head tank, a carriage, a supply mechanism, a maintenance / recovery mechanism, a main scanning movement mechanism in which at least one of the configurations is combined with a liquid discharge head, and the like.

Here, the term "integration" means, for example, a liquid discharge head and a functional component, a mechanism in which the mechanism is fixed to each other by fastening, bonding, engagement, etc., or one in which one is movably held with respect to the other. include. Further, the liquid discharge head, the functional component, and the mechanism may be configured to be detachable from each other.

The main scanning movement mechanism shall include a single guide member. Further, the supply mechanism includes a single tube and a single loading unit.

The "liquid discharge head" is a functional device that discharges and ejects liquid from a nozzle. Piezoelectric actuators (laminated piezoelectric elements or thin film piezoelectric elements), thermal actuators that use electric heat conversion elements such as heat-generating resistors, and electrostatic actuators that consist of vibrating plates and counter electrodes are used as energy sources for discharging liquids. Be done.

In the present specification, "paper" is not limited to paper as a material, but includes OHP, cloth, glass, substrate, etc., and means a material to which ink droplets, other liquids, etc. can adhere, and is a recording medium. , Recording media, recording paper, recording paper, etc. are included. In addition, image formation, recording, printing, printing, and printing are all synonyms.

Unless otherwise specified, "ink" is not limited to what is called ink, but is a general term for all liquids that can form images, such as recording liquids, fixing treatment liquids, and liquids. Also included are, for example, DNA samples, resists, pattern materials, resins and the like.

The "image" is not limited to a two-dimensional image, but also includes an image given to a three-dimensionally formed object and an image formed by three-dimensionally modeling the three-dimensional object itself.

The present invention has been described in detail above using the embodiments. This embodiment is an example, and can be variously modified and used within a range that does not deviate from the gist. For example, a plurality of embodiments may be combined.

1 Device body 2 Support stand 3 Guide rod 4 Guide stay 5 Carriage 6a, 6b, 6c Recording head 7 Platen 8 Maintenance / recovery device 9 Main cartridge 10 Main scanning mechanism 11 Drive motor 12 Drive pulley 13 Driven pulley 14 Timing belt 20 Paper 21 Paper feed means 22, 29 Base plate 22b Female thread 23 Carriage side plate 24, 28 Position adjustment bracket 24a Through hole 25 Adjustment screw 26 Compression spring 27 Position adjustment means

Japanese Patent Application Laid-Open No. 2003-266858

Claims (6)

A liquid ejection head with multiple nozzles that eject droplets,
A base plate that holds one or more of the liquid discharge heads,
A plurality of carriage side plates for holding the base plate, and
In a liquid discharge unit including at least one position adjusting means provided between the base plate and the plurality of carriage side plates.
The position adjusting means is
A bracket for adjusting the position, which is provided with a through hole and is provided on the carriage side plate,
An adjusting screw that is inserted through the through hole and the base plate to adjust the separation distance between the position adjusting bracket and the base plate.
A liquid discharge unit having an elastic member interposed between the position adjusting bracket and the base plate and urging the base plate in a direction away from the position adjusting bracket. The liquid discharge unit according to claim 1, wherein the adjusting screw passes through the through hole and is screwed into the base plate, and the elastic member is provided around the axis of the adjusting screw. .. The liquid discharge unit according to claim 1 or 2, wherein the position adjusting means is provided on each of the plurality of carriage side plates arranged at both ends of the base plate. The liquid discharge unit according to any one of claims 1 to 3, wherein at least one of the position adjusting brackets has a convex seating surface to which the head bearing surface of the adjusting screw abuts. .. The liquid discharge unit according to any one of claims 1 to 4, wherein at least one end of the base plate has a curved surface shape. A liquid discharge device including the liquid discharge unit according to any one of claims 1 to 5.

Images