JP2015174388A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device capable of accurately determining a relative position of a recording head of each head holder when a plurality of the head holders are held by a reference member in a carriage.SOLUTION: Head holders 51A and 51B for holding a recording head are held on hooking parts to a reference axis member 71 in a carriage 5, and an adjusting member 90 for adjusting an inclination to the reference axis member 71 in a plane of the head holder 51B in the horizontal direction thereof is provided by setting the head holder 51A as a reference. The adjusting member 90, which is a cam member mounted on a rotating shaft 90a in a vertical direction, is arranged between a hooking part 53Ba of the head holder 51B and the reference axis member 71 in a direction along a sub-scanning direction.

Description

  The present invention relates to an image forming apparatus.

  As an image forming apparatus such as a printer, a facsimile, a copying machine, a plotter, or a complex machine of these, for example, a liquid discharge recording type image forming apparatus using a liquid discharge head (droplet discharge head) for discharging droplets as a recording head An ink jet recording apparatus is known.

  Conventionally, for example, a plurality of head holders for holding a recording head are held on a reference member arranged on a carriage, and the plurality of head holders are provided with reference surfaces that come into contact with each other in the main scanning direction and determine relative positions of each other. The recording head is positioned with reference to the reference surface of the head holder, is held by the head holder, and includes a pressurizing unit that presses at least one head holder toward the other head holder. (Patent Document 1).

  Also, in the configuration as described above, an eccentric cam is used to move the head holder in the sub-scanning direction so that the relative positional accuracy of the recording head can be positioned with high accuracy by being mounted on a plurality of head holders. Is known (Patent Document 2).

JP 2013-063530 A JP 2013-063526 A

  As described above, in the configuration in which the plurality of head holders are held on the reference member of the carriage, the relative position of the recording head of each head holder can be positioned with high accuracy without changing the gap between the recording head and the medium. It is necessary to.

  The present invention has been made in view of the above problems, and an object of the present invention is to make it possible to easily adjust the relative position of the head of each head holder with high accuracy.

In order to solve the above problems, an image forming apparatus according to the present invention provides:
A plurality of recording heads having nozzles for discharging droplets;
A plurality of head holders for holding the recording head;
A carriage for holding the head holder,
The carriage is movable along a guide member arranged in the main scanning direction,
The carriage has a reference member arranged in the same direction as the guide member,
The plurality of head holders are respectively held side by side with the reference member,
An adjusting means for adjusting an inclination with respect to the reference member in a horizontal plane of the head holder is provided between at least one of the head holder and the reference member.

  According to the present invention, the relative position of the head of each head holder can be easily adjusted with high accuracy.

1 is an external perspective view illustrating an entire configuration of an example of an image forming apparatus according to the present invention. It is a perspective explanatory view of a carriage scanning mechanism part of the same device. It is a typical perspective explanatory view of a carriage part explaining a state before mounting a head holder in a 1st embodiment to a carriage to the present invention. It is a perspective explanatory view of the carriage part explaining the state where the head holder was similarly attached to the carriage. It is side surface explanatory drawing of the carriage part with which it uses for description of the holder pressurization means which pressurizes the head holder in the embodiment. It is a perspective explanatory view similarly. It is typical plane explanatory drawing of the carriage part in 1st Embodiment of this invention. It is a typical side surface explanatory view of a carriage part. FIG. 6 is a schematic plan explanatory view of a carriage part before adjustment for explaining an example of the operation of the embodiment. It is explanatory drawing explaining the droplet landing position before adjustment similarly. FIG. 6 is a schematic plan view of the carriage portion after adjustment in the same manner. It is explanatory drawing explaining the droplet landing position after adjustment similarly. FIG. 10 is a schematic side view illustrating a carriage portion before adjustment for explaining another example of the operation of the embodiment. It is explanatory drawing explaining the droplet landing position before adjustment similarly. FIG. 6 is a schematic plan view of the carriage portion after adjustment in the same manner. It is explanatory drawing explaining the droplet landing position after adjustment similarly. It is typical plane explanatory drawing of the carriage part with which it uses for description of 2nd Embodiment of this invention. It is typical side surface explanatory drawing of the carriage part with which it uses for description of 3rd Embodiment of this invention. It is typical side surface explanatory drawing of the carriage part with which it uses for description of 4th Embodiment of this invention. It is typical plane explanatory drawing of the carriage part with which it uses for description of 5th Embodiment of this invention. It is a principal part perspective explanatory drawing of a head holder similarly. FIG. 22 is a cross-sectional explanatory view of a hook portion taken along line CC of FIG. 21. It is a perspective explanatory view of the reference shaft member of the embodiment. It is sectional explanatory drawing of the same reference | standard shaft member and a hook part. It is sectional explanatory drawing of the reference | standard shaft member and hook part in 6th Embodiment of this invention.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. An example of an image forming apparatus according to the present invention will be described with reference to FIGS. FIG. 1 is an explanatory perspective view showing the overall configuration of the apparatus, and FIG. 2 is an explanatory perspective view of the carriage scanning mechanism.

This image forming apparatus is a serial type ink jet recording apparatus, and includes an apparatus main body 1 and a support base 2 that supports the recording apparatus main body 1.

  Guide rods 3 and guide stays 4, which are guide members arranged in the main scanning direction on both side plates (not shown), are spanned inside the apparatus main body 1, and a carriage 5 is moved over these guide rods 3 and guide stays 4. It is slidably held in the direction A (main scanning direction).

  On the carriage 5, 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) is mounted. Although not shown, each recording head 6 is integrally provided with a head tank that supplies ink to each recording head 6.

  The main scanning mechanism 10 that moves and scans the carriage 5 is disposed on one side in the main scanning direction, a driving pulley 12 that is rotationally driven by the driving motor 11, and on the other side in the main scanning direction. The driven pulley 13 is provided, and a timing belt 14 that is a pulling member wound between the drive pulley 12 and the driven pulley 13 is provided. The driven pulley 13 is tensioned outward (in a direction away from the drive pulley 12) by a tension spring (not shown).

  Among the main scanning areas in the carriage 5, in the recording area, the paper 20 is intermittently moved in the direction orthogonal to the main scanning direction of the carriage 5 by the suction conveyance unit 7 (sub-scanning direction, paper conveyance direction: arrow B direction). Be transported.

  In addition, a maintenance / recovery mechanism 8 that performs maintenance / recovery of the recording head 6 is disposed in one end side region of the main scanning region. Further, a main cartridge 9 containing each color ink to be supplied to the sub tank of the recording head 6 is located outside the carriage movement area in the main scanning direction or in the other end side area of the main scanning area. And is detachably mounted.

  In addition, roll paper (hereinafter referred to as “paper”) 20 is set in the paper supply unit 21, but roll papers having different sizes in the width direction can be set. The sheet 20 conveyed from the sheet feeding unit 21 is conveyed from the rear of the apparatus main body 1 to the front by the conveying unit to the recording area.

  Then, the carriage 5 is moved in the main scanning direction, and the recording head 6 is driven according to the image information to eject droplets while intermittently feeding the paper 20 by the suction conveyance unit 7. A required image is formed. Further, the paper 20 after the image formation is cut to a predetermined length and discharged to a paper discharge tray (not shown) arranged on the front side of the apparatus main body 1.

  Next, the configuration of the carriage 5 will be described with reference to FIGS. FIG. 3 is a schematic perspective explanatory view of the carriage portion explaining a state before the head holder is mounted on the carriage in the apparatus, and FIG. 4 is a perspective explanatory view of the carriage portion illustrating a state where the head holder is mounted on the carriage. .

  The carriage 5 holds a black head holder 51A and a color head holder 51B side by side in the main scanning direction.

  The head holder 51A is equipped with two recording heads 6A and 6B that discharge black droplets arranged in a staggered manner in the sub-scanning direction. The head holder 51B is mounted with three recording heads 6C, 6D, and 6E that discharge yellow, magenta, and cyan droplets at the same position in the sub-scanning direction as the recording head 6A. As described above, when the recording heads are not distinguished, they are referred to as “recording head 6”. One recording head 6 may be held by the head holders 51A and 51B.

Here, the carriage 5 is provided with a reference shaft member 71 as a reference member in the same direction as the guide rod 3. The head holders 51 </ b> A and 51 </ b> B (hereinafter referred to as “head holder 51” when not distinguished from each other, the same applies to other members) have hook-shaped hook portions 53 that are detachably fitted into the reference shaft member 71. The head holders 51 </ b> A and 51 </ b> B are held by the carriage 5 by hooking the hook portion 53 on the reference shaft member 71. Note that the reference shaft member 71 may have a cylindrical shape or a polygonal shape.

  When exchanging the head, for example, when exchanging the recording head 6, the head holder 51 is removed from the reference shaft member 71, and the replaced head holder 51 is hooked on the reference shaft member 71 and held. Thereby, the head position accuracy of the replaced head holder 51 can be reproduced, and high position accuracy can be obtained for the recording head 6 of the other head holder 51.

  Next, the pressure structure of the head holder will be described with reference to FIGS. FIG. 5 is an explanatory side view of a carriage portion for explaining the pressurizing structure, and FIG. 6 is a schematic perspective explanatory view in a state in which a holder pressurizing cover member as a pressurizing member is assembled.

  As shown in FIG. 5, the head holders 51 </ b> A and 51 </ b> B have at least one abutting portion 58 that comes into contact with the carriage 5. The head holders 51A and 51B have two hook portions 53Aa, 53Ab, 53Ba, and 53Bb, respectively, in the main scanning direction.

  A holder pressurizing mechanism 80 is provided as a pressurizing unit that pressurizes the head holder 51 toward the carriage 5 with the reference shaft member 71 as a rotation center.

  The holder pressurizing mechanism 80 includes a holder pressurizing cover member 82 having a rear end portion 82b rotatably supported by a shaft 81 on the carriage 5. The cover member 82 is a substantially flat member as shown in FIG. 6, for example.

  Here, the cover member 82 is common to the two head holders 51A and 51B, but a cover member may be provided for each of the head holders 51A and 51B.

  On the distal end side of the cover member 82, there is a pressurizing part 182 (a general term for the pressurizing parts 182a and 182b) that contacts the head holder 51 from above. An elastic member 83 such as a tension coil spring is provided between the cover member 82 and the carriage 5, and the pressing portion 182 of the holder pressurizing cover member 82 is a head by the elastic pulling force of the elastic member 83. The holder 51 is pressed (pressed) in the direction of the white arrow.

  As a result, the head holder 51 is urged to rotate in the clockwise direction (in the direction of the white arrow) in FIG. 5 around the reference shaft member 71 by the cover member 82 and is pressed against the reference shaft member 71 and the carriage 5. The postures of the head holders 51A and 51B are defined. That is, the posture of the head holder 51 can be determined simply by hooking the head holder 51 on the reference shaft member 71 and closing the cover member 82 (covering the upper portion of the head holder 51).

  As a result, even when head replacement is performed by the user, the head position can be easily determined with high accuracy, and head replacement is facilitated.

  Next, a first embodiment of the present invention will be described with reference to FIGS. FIG. 7 is a schematic plan view of the carriage portion in the same embodiment, and FIG. 8 is a schematic side view of the carriage portion. In addition, there is also a part illustrated in a transparent state for explanation.

  In the present embodiment, the head holders 51 </ b> A and 51 </ b> B are held on the carriage 5 by the reference shaft member 71 and are brought close to one inner surface of the carriage 5 by a pressing spring 85 that is a pressing unit disposed on the carriage 5. ing.

  Further, the head holders 51A and 51B are in contact with the contact portion 54 by the pressure spring 85, and the distance in the main scanning direction between the head holder 51A and the head holder 51B is determined.

  In addition, a spring member 55 such as a leaf spring is disposed between the upstream surface (referred to as the back surface) 55 of the two hooking portions 53Ba and 53Bb of the head holder 51B and the carriage 5, and the hooking portions 53Ba, 53Bb is pressurized toward the reference shaft member 71 side.

  An adjustment member 90 is provided as an adjustment unit that adjusts the inclination with respect to the reference shaft member 71 in the horizontal plane of the head holder 51B with reference to the head holder 51A of the two head holders 51A and 51B.

  The adjustment member 90 is a cam member provided on the rotary shaft 90a arranged in the vertical direction, and as shown in FIG. 8, the hooking portion 53Ba of the head holder 51B and the reference shaft member 71 in the direction along the sub-scanning direction. It is arranged between.

  Accordingly, since the distance between the reference shaft member 71 and the hook portion 53Ba of the head holder 51B changes by rotating the adjustment member 90, the reference shaft member 71 in the horizontal plane of the head holder 51B with respect to the head holder 51A. The inclination with respect to can be adjusted.

  In this case, since the head holder 51B is rotated only in the horizontal plane, the inclination of the head holder 51 can be adjusted without changing the distance (gap) between the recording head 6 and the paper 20.

  Since the adjustment member 90 is a cam member, the inclination of the head holder 51B relative to the head holder 51A can be adjusted by accessing and rotating the cam member from above the carriage on the actual machine. For example, when the droplet landing position shift becomes a problem in the image inspection in the assembly process, the droplet landing position can be adjusted on the actual machine without returning the apparatus to the adjustment process.

  As described above, the adjustment member 90 is arranged between the one end side hook portion 53Ba of the head holder 51B and the reference shaft member 71, but the other end side hook portion 53Bb of the head holder 51B and It can also be arranged between the reference shaft member 71.

  Next, an example of the operation of the present embodiment will be described with reference to FIGS. 9 is a schematic plan explanatory view of the carriage part before adjustment, FIG. 10 is also an explanatory view explaining the droplet landing position before adjustment, FIG. 11 is a schematic plan explanatory view of the carriage part after adjustment, and FIG. It is explanatory drawing explaining the droplet landing position after adjustment.

  As shown in FIG. 9, when the head holder 51B is inclined with respect to the head holder 51A (in the horizontal plane), as shown in FIG. 10, the nozzle array of the recording head 6 of the head holder 51A. The droplets 93 ejected from the nozzle rows of the recording head 6 of the head holder 51B are tilted and land on the paper 20 with respect to the droplets 92 ejected from the head.

  For this reason, the landing positions of the droplet 92 and the droplet 93 are displaced, and the image quality is deteriorated.

  Therefore, as shown in FIG. 11, the adjustment member 90 is rotated to rotate the head holder 51B in the direction of the arrow in the horizontal plane, thereby adjusting the inclination of the head holder 51B relative to the reference shaft member 71.

  Accordingly, as shown in FIG. 12, the droplets 92 ejected from the nozzle array of the recording head 6 of the head holder 51A and the droplets 93 ejected from the nozzle array of the recording head 6 of the head holder 51B are substantially parallel ( (Including equilibrium) and landing position deviation is reduced.

  In this way, it is possible to adjust the droplet landing position deviation between the head holder 51A and the head holder 51B.

  Next, another example of the operation of the present embodiment will be described with reference to FIGS. 13 is a schematic side view of the carriage portion before adjustment, FIG. 14 is also an explanatory view for explaining the landing position before adjustment, FIG. 15 is a schematic plan view of the carriage portion after adjustment, and FIG. It is explanatory drawing explaining the droplet landing position after adjustment.

  As shown in FIG. 13, when the tip end side of the head holder 51B in the sub-scanning direction is lowered in the height direction with respect to the head holder 51A and is attached to the carriage 5, as shown in FIG. 14, the head holder 51A and the head holder The landing positions of the droplets 92 and 93 ejected from the respective recording heads 51B are shifted in a letter C shape.

  Therefore, as shown in FIG. 15, by adjusting the inclination of the head holder 51B in the horizontal plane by the adjustment member 90, as shown in FIG. 16, the droplet landing position deviation between the head holder 51A and the head holder 51B is adjusted. Can do.

  Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 17 is a schematic plan explanatory view of a carriage portion for explaining the embodiment.

  In the present embodiment, in the hooking portions 53Ba and 53Bb of the head holder 51B, the adjustment member 90 is arranged on one end side in the main scanning direction, and the hook 53Bb on the other end side where the adjustment member 90 is not arranged is A contact portion 57 that makes point contact with the reference shaft member 71 is provided. The contact portion 57 has, for example, an arc shape.

  In this way, on the side where the adjustment member 90 is not disposed, the contact portion 57 contacts the reference shaft member 71 at a point, so that even when the head holder 51B is inclined by the adjustment member 90, the contact portion 57 contacts the reference shaft member 71. The change in the contact state of the part 57 is kept small.

  Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 18 is a schematic side view illustrating a carriage portion used for describing the embodiment.

  In the present embodiment, the adjustment member 90 is a tapered member. Also in this case, since the distance between the reference shaft member 71 and the hook portion 53Ba is changed by arranging the adjustment member 90 so as to be movable in the vertical direction, the inclination of the head holder 51B can be adjusted. At this time, since the taper surface of the adjustment member 90 faces upward as shown in FIG. 18, an action of pressing the reference shaft member 71 against the lower surface of the hook portion 53Ba also occurs, so that the position of the head holder 51B is not easily changed.

  Next, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 19 is a schematic side view of a carriage portion used for describing the embodiment.

  In the present embodiment, the adjustment member 90 is a screw member. Also in this case, since the distance between the reference shaft member 71 and the hook portion 53Ba is changed by moving the adjustment member 90 back and forth in the medium transport direction, the inclination of the head holder 51B can be adjusted.

  Next, a fifth embodiment of the present invention will be described with reference to FIGS. FIG. 20 is a schematic plan view of a carriage portion for explaining the embodiment, FIG. 21 is a perspective view of the main part of the head holder, and FIG. 22 is a cross-sectional view of a hook portion taken along line CC in FIG. FIG. 23 is a perspective explanatory view of the reference shaft member of the embodiment, and FIG. 24 is a cross-sectional explanatory view of the reference shaft member and the hook portion.

  As shown in FIG. 23, the reference shaft member 171 is provided with an eccentric cam portion 172 at a portion in contact with the hook portion 53Ba of the head holder 51B. The maximum outer peripheral diameter of the eccentric cam portion 172 is smaller than the outer peripheral diameter other than the eccentric cam portion 172.

  On the other hand, as shown in FIGS. 21 and 22, the hook portion 53Ba of the head holder 51B has a contact portion 154 that contacts the circumferential surface (cam surface) of the eccentric cam portion 172, and the main scanning direction with the contact portion 154 interposed therebetween. On both sides, a contact portion 155 that directly contacts the peripheral surface of the reference shaft member 171 other than the eccentric cam portion 172 is provided in the height direction.

  Further, the hook portion 53Bb of the head holder 51B is in contact with the reference shaft member 171 at a portion 173 (see FIG. 23) other than the eccentric cam portion 172 of the reference shaft member 171.

  With this configuration, by rotating the reference shaft member 171, the distance between the shaft center of the reference shaft member 171 and the contact portion 154 of the hook portion 53Ba of the head holder 51B that contacts the eccentric cam portion 172 changes.

  Therefore, the inclination with respect to the reference shaft member 171 in the horizontal plane of the head holder 51B can be adjusted.

  As described above, since the inclination can be adjusted only by rotating the reference shaft member 171, the relative position of the head of each head holder can be easily adjusted with high accuracy.

  Next, a sixth embodiment of the present invention will be described with reference to FIG. FIG. 25 is a cross-sectional explanatory view of the reference shaft member and the hook portion in the same embodiment.

  The reference shaft member 171 is provided with an eccentric cam portion 172 at a portion in contact with the hook portion 53Ba of the head holder 51B. Here, the maximum outer peripheral diameter of the eccentric cam portion 172 is larger than the outer peripheral diameter other than the eccentric cam portion 172.

  On the other hand, the hook portion 53Ba of the head holder 51B has a relief portion 175 that escapes the eccentric cam portion 172 in the height direction. That is, by providing the relief portion 175, the hook portion 53Ba can contact the peripheral surface of the reference shaft member 171 other than the eccentric cam portion 172 in the height direction, so that fluctuation in the height direction can be eliminated. The maximum outer peripheral diameter of the cam portion 172 can be made larger than the outer peripheral diameter other than the eccentric cam portion 172, and the eccentric cam portion can be easily formed on the reference shaft member 171.

  The reference shaft member having the eccentric cam portion in these embodiments can also be applied when holding one head holder.

  In the present application, “paper” is not limited to paper, and includes materials called media, recording media, recording media, recording paper, recording paper, and the like. In addition, image formation, recording, printing, printing, and printing are all synonymous.

  In addition, “image formation” not only applies an image having a meaning such as a character or a figure to a medium but also applies an image having no meaning such as a pattern to the medium (simply applying a droplet to the medium). To land).

  The “ink” is not limited to an ink unless otherwise specified, but includes any liquid that can form an image, such as a recording liquid, a fixing processing liquid, or a liquid. Used generically. For example, DNA samples, resists, pattern materials, resins and the like are also included.

  In addition, the “image” is not limited to a planar image, and includes an image given to a three-dimensionally formed image and an image formed by three-dimensionally modeling a solid itself.

  Further, the image forming apparatus includes both a serial type image forming apparatus and a line type image forming apparatus, unless otherwise limited.

DESCRIPTION OF SYMBOLS 1 Apparatus main body 5 Carriage 6, 6A-6D Recording head 51, 51A, 51B Head holder 53, 53A, 53B Hook part 71,171 Reference shaft member (reference member)
90 Adjustment member 172 Eccentric cam

Claims (8)

A plurality of recording heads having nozzles for discharging droplets;
A plurality of head holders for holding the recording head;
A carriage for holding the head holder,
The carriage is movable along a guide member arranged in the main scanning direction,
The carriage has a reference member arranged in the same direction as the guide member,
The plurality of head holders are respectively held side by side with the reference member,
An image forming apparatus comprising: an adjusting unit that adjusts an inclination of the head holder with respect to the reference member in a horizontal plane between the at least one head holder and the reference member. 2. The head holder provided with the adjusting means has the adjusting means disposed on one end side in the main scanning direction, and the other end side is in point contact with the reference member. Image forming apparatus. The image forming apparatus according to claim 1, wherein the adjusting unit is a cam member. The image forming apparatus according to claim 1, wherein the adjusting unit is a tapered member. The image forming apparatus according to claim 1, wherein the adjusting unit is a screw member. A plurality of recording heads having a plurality of nozzles for discharging droplets;
A plurality of head holders for holding the recording head;
A carriage for holding the head holder,
The carriage is movable along a guide member disposed in a main scanning direction;
The carriage has a reference member disposed in the same direction as the guide member,
The plurality of head holders are respectively held side by side with the reference member,
The reference member is provided with an eccentric cam portion at a portion in contact with at least one of the head holders,
An image forming apparatus, wherein the reference member is rotated to adjust an inclination relative to the reference member in a horizontal plane of the head holder with which the eccentric cam portion contacts. The reference member and the head holder are in contact with each other in the medium conveyance direction at the eccentric cam portion, and are in direct contact with each other in the height direction other than the eccentric cam portion. Image forming apparatus. The head holder has a plurality of contact portions in contact with the reference member in the main scanning direction, and the eccentric cam portion is provided in one of the plurality of contact portions. The image forming apparatus described in 1.

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