JP2008023815A - Inkjet printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make the width size of an inkjet printer small while an installation position accuracy of a media sensor is improved. <P>SOLUTION: A positioning wall part 113B for positioning the media sensor 116 is provided at a sub-tank 113, and an emission hole 111B is formed in a front end plate 111. The media sensor 116 can be attached to the front end plate 111 by a high positioning accuracy to the front end plate. At the same time, the width size of a printer part (inkjet printer) can be made small by making a width size of the front end plate 111 small. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an ink jet printer that forms an image on a recording medium by ejecting ink droplets onto the recording medium.

In recent years, there has been an increasing demand for an inkjet printer having a so-called “borderless print function” that performs printing on the entire printing surface of a recording medium such as recording paper. In order to realize this borderless printing function, for example, in the invention described in Patent Document 1, an end of a recording medium is detected by an optical media sensor, and ink is detected based on the detected end of the recording medium. Controls the timing of ejecting drops.
JP 2004-243726 A

  However, in the invention described in Patent Document 1, since the media sensor is arranged on the side surface side of the front end plate, that is, the scanning direction end portion side of the front end plate, the width dimension of the front end plate becomes large, In response to this, there is a problem that the width dimension of the ink jet printer (the dimension of the portion parallel to the scanning direction) increases.

  Also, if the media sensor installation position accuracy is low, the end of the recording medium cannot be detected accurately, so the timing of ejecting ink droplets cannot be accurately controlled, and the front end with the recording medium in between There is a problem that ink adheres to the platen disposed on the side opposite to the plate.

  Note that when ink adheres to the platen, the ink that has adhered to the platen adheres to the newly transported recording medium, which causes a problem that unnecessary ink adheres to the recording medium.

  An object of the present invention is to reduce the width dimension of an ink jet printer while improving the accuracy of the installation position of a media sensor.

  In order to achieve the above object, according to the first aspect of the present invention, in the first aspect of the present invention, a carriage that ejects ink droplets onto a recording medium, and a recording medium that holds the recording medium is disposed opposite to the carriage with a predetermined gap. An ink jet printer having a platen, wherein a carriage emits light toward the platen and detects an edge of the recording medium by detecting reflected light, and an ejection for ejecting ink droplets onto the recording medium A front end plate in which a radiation port through which light emitted from the port and the media sensor passes is formed; a tank that communicates with the ejection port side; and a tank that stores ink supplied to the ejection port; a media sensor and a tank And a casing with a front end plate and a tank assembled therein. Wherein the positioning wall for positioning the media sensor against contact with a portion with emission opening of capacitors are provided.

Incidentally, since the tank communicates with the injection port, the tank is usually assembled to the casing with high positioning accuracy with respect to the injection port, that is, the front end plate.
In the present invention, since the positioning wall portion for positioning the media sensor is provided in the tank, the media sensor can be assembled to the front end plate with high positioning accuracy with respect to the front end plate. Can be assembled with high positioning accuracy with respect to the radiation opening.

  Further, since the radiation port is provided in the front end plate and the media sensor is accommodated in the casing, compared to the front end plate described in Patent Document 1 in which the media sensor is disposed on the side surface of the front end plate, The width of the front end plate can be reduced.

Therefore, according to the present invention, it is possible to reduce the width dimension of the ink jet printer while improving the installation position accuracy of the media sensor.
Further, the invention according to claim 2 is characterized in that the radiation port is covered with a film having water repellency.

  As a result, it is possible to prevent the ink from adhering to the film covering the radiation port while preventing the radiation port from being blocked by the ink, so that the end of the recording medium can be detected. It is possible to prevent the occurrence of problems such as inability to occur.

  In the present embodiment, the ink jet printer according to the present invention is applied to a multi-function device having a printer function, a scanner function, a copy function, a facsimile function, and the like, and the embodiment of the present invention will be described below with reference to the drawings. .

  Note that the multi-function device according to the present embodiment is connected to a computer and recorded on a recording medium (hereinafter referred to as a recording sheet) such as a recording sheet or an OHP sheet based on image data or document data transmitted from the computer. An image including characters can be recorded, or image data output from a digital camera connected to an external device such as a digital camera can be recorded on a recording sheet.

(First embodiment)
1. FIG. 1 is an external perspective view of the multi-function device 1, and FIG. 2 is a side view of the multi-function device 1. Incidentally, the broken line part of FIG. 2 shows the device accommodated in the multi-function device 1.

  As shown in FIG. 1, an ink jet recording type printer unit 100 for forming an image on recording paper is provided at the lower part of the multi-function device 1, and a scanner unit 200 for reading an image of an original is provided at the upper part. ing.

  As shown in FIG. 2, the scanner unit 200 of the multi-function device 1 according to this embodiment includes an FBS (Flatbed Scanner) function for reading a document in a state where the document is placed on the document placement unit 210, and an automatic document. A conveyance mechanism (ADF: Auto Document Feeder) 220 is provided.

  Further, as shown in FIG. 1, an operation panel 10 is provided on the front upper inclined surface of the multi-function device 1 for operation setting of the printer unit 100 and the scanner unit 200, and a memory card or the like is provided on the front side. A slot portion 20 into which a storage medium is inserted and an insertion port 30 for inserting and mounting a paper feed tray 151 to be described later are provided.

2. Printer Unit FIG. 3 is a schematic diagram of the printer unit 100 (portion indicated by a broken line in FIG. 2), and FIG. 4 is a diagram of the ink refill unit 190, the image recording unit 110, and the like viewed from the upper surface side.

  The printer unit 100 includes an image recording unit 110 that forms an image on a recording sheet, a feeder unit 150 that supplies the recording sheet to the image recording unit 110, an ink refill unit 190 that supplies ink to the image recording unit 110, and the like. Has been.

2.1. Feeder section (see Fig. 3)
At the bottom of the multi-function device 1 (printer unit 100), as shown in FIG. 3, a paper feed tray 151 on which a large number of recording papers are placed is disposed. A separation inclined plate 152 for separating and guiding the recording paper placed on the paper feed tray 151 upward is provided on the right side of the paper.

  A recording paper conveyance path L1 is formed upward from the separation inclined plate 152. The conveyance path L1 extends upward and then curves to the left of the paper surface. It extends to the side, passes through the image recording unit 110, and communicates with the paper discharge tray 153.

  For this reason, the recording paper stored in the paper feed tray 151 is guided to make a U-turn from below to the image recording unit 110, and after the image is recorded on the recording paper by the image recording unit 110, The paper is discharged to a paper discharge tray 153.

The paper feed roller 154 separates the recording paper loaded on the paper feed tray 151 one by one and supplies it to the transport path L1, and its structure is the same as a known one.
That is, for example, the paper feed roller 154 is pivotally supported at the tip of a paper feed arm 155 that moves up and down so as to be able to contact and separate from the paper feed tray 151 and is connected to a motor via a drive transmission mechanism. The paper feed arm 155 is provided so as to be rotatable around the base end shaft 156, and in a standby state, the paper feed arm 155 is flipped up by a paper feed clutch or a spring (not shown) to supply recording paper. Swings down.

2.2. Image recording unit 110
5 is a view of the head unit (carriage) 112 as viewed from the ejection port (nozzle) side, FIG. 6 is an external perspective view of the head unit 112 as viewed from the ejection port side, and FIG. FIG. 8 is a top view showing a state where the cap 114A and the head unit substrate 115 are removed, and FIG. 8 is a cross-sectional view taken along the line AA of FIG.

  9 is a side view of the head unit 112, FIG. 10 is a left side view (rear surface of the head unit 112) of FIG. 9, FIG. 11 is a cross-sectional view taken along line AA of FIG. 9 is a cross-sectional view taken along the line BB in FIG. 9, and FIG. 13 is a perspective view of the head unit substrate 115. In FIG. 9, the recording paper transport direction advance side is the front side, and the recording paper transport direction backward side is the rear side.

  As shown in FIG. 11, the head unit 112 includes a front end plate 111 and a head unit casing 114 that constitutes a sub tank 113. The head unit 112 is a rail that extends in the left-right direction of the multi-function device 1. A member 158 (see FIG. 4) is supported so as to be movable in the main scanning direction.

  Further, a front end plate 111 is provided at a position facing the platen 157 (see FIG. 3) in the head unit 112 (head unit casing 114), and the front end plate 111 is provided as shown in FIG. In addition, an ejection port 111A for ejecting ink droplets is provided.

  Incidentally, since the actual ejection port 111A is a minute hole, the ejection port 111A is exaggerated in FIG. 5, and the first row of ejection ports 111A from the left in FIG. 5 is for black ink. The second jet port 111A from the left is the yellow ink jet port, the third jet port 111A from the left is the cyan ink jet port, and is the fourth from the left. The rows of the ejection ports 111A are magenta ink ejection ports.

  As shown in FIG. 3, the platen 157 is disposed opposite to the front end plate 111 (injection port 111A) with a predetermined gap to hold a recording sheet. It is arranged on the lower side of the head unit 112).

  Further, as shown in FIGS. 11 and 7, sub-tanks 113 corresponding to the respective colors are provided in the head unit casing 114 above the front end plate 111 (injection port 111 </ b> A). , Tank means for temporarily storing ink ejected from the ejection port 111A and stably supplying the ink to the ejection port 111A side.

  In FIG. 7, the communication port 113A is a passage that allows the sub tank 113 and the ejection port 111A (front end plate 111) to communicate with each other, and the ink in the sub tank 113 is transferred to the ejection port 111A via the communication port 113A. Supplied.

  Further, as shown in FIG. 4, the ink stored in each sub tank 113 is supplied from each of a plurality of ink cartridges 191 (see FIG. 1) via the ink tube 192. A main tank portion for storing ink to be supplied to the sub tank 113 is configured.

  The ink cartridge 191 is detachably attached to the ink refill unit 190, and the ink refill unit 190 is the right end portion on the front side of the multi-function device 1, as shown in FIGS. As shown in FIG. 3, the ink level when the ink cartridge 191 is fully filled is incorporated at a position lower than the position of the ejection port 111A.

  As shown in FIGS. 11 and 12, a media sensor 116 for detecting the end of the recording paper is housed in the front side of the head unit casing 114, and the media sensor 116 is configured with a platen 157 (recording device). The light emitting element (not shown) which radiates | emits light toward the (paper) side, the light receiving element (not shown) which detects the reflected light of the light radiated | emitted from the light emitting element, etc. are comprised.

  The media sensor 116 is housed in the head unit casing 114 in a state of being fixed to the head unit substrate 115 as shown in FIG. 13, and the front end plate as shown in FIGS. On the front end plate 111 side of the head unit casing 114 and the head unit casing 114, there is provided a radiation port 111B through which light emitted from the media sensor 116 passes.

  Further, on the head unit substrate 115 side of the sub tank 113, a positioning wall portion 113B for positioning the media sensor 116 with respect to the radiation port 111B by contacting the head unit substrate 115 side of the media sensor 116 is provided. As shown in FIG. 7, the positioning wall portion 113 </ b> B is configured by a rectangular tubular inner wall surface.

In the present embodiment, the sub tank 113 is made of a relatively hard resin such as polypropylene, and the positioning wall portion 113B is integrally formed with the sub tank 113.
Further, as shown in FIG. 11, the radiation port 111B is covered with a thin film 111C having water repellency and translucency, and this thin film 111C is formed from the outer side (platen 157) side of the front end plate 111. 111B is covered.

  Incidentally, the sub tank 113 is fixed to the head unit casing 114 by fastening means (not shown) such as a P screw, and a cap 114A for closing the opening of the head unit casing 114 is a locking protrusion provided on the head unit casing 114. It is assembled in a detachable manner.

  The head unit substrate 115 is fixed in the head unit casing 114 while being sandwiched between the cap 114A and the sub-tank 113 via an elastic plate material such as a sponge 115A disposed on the inner wall side of the cap 114A.

  By the way, as shown in FIG. 3, a drive roller 159 and a pressure roller 160 are provided upstream of the head unit 112 (platen 157) in the paper conveyance direction. The recording paper transported through L1 is pinched, and the recording paper is transported onto the platen 157 in conjunction with the reciprocating movement of the carriage.

The driving roller 159 is rotated by obtaining a driving force from an electric motor (not shown), and the pressing roller 160 is driven to rotate by pressing the recording sheet toward the driving roller 159.
Further, a paper discharge roller 161 and a pressure roller 162 are provided downstream of the head unit 112 (platen 157) in the paper conveyance direction. The paper discharge roller 161 and the pressure roller 162 are discharged from the image recording unit 110. The recording sheet on which the printing has been completed while pinching the received recording sheet is conveyed to the discharge tray 153.

  Note that the paper discharge roller 161 rotates mechanically (synchronously) with the rotation of the driving roller 159, and the pressing roller 162 is driven to rotate by pressing the recording paper toward the paper discharge roller 161. In addition, since the pressing roller 162 is pressed against the recorded recording paper, irregularities are formed on the contact surface with the recording paper to form a spur (gear) shape so as not to deteriorate the image recorded on the recording paper. Yes.

3. Features of Multi-Function Device 1 (Printer Unit 100) According to this Embodiment As described above, since the sub tank 113 communicates with the ejection port 111A, the sub tank 113 is higher than the ejection port 111A, that is, the front end plate 111. The head unit casing 114 is assembled with positioning accuracy.

  In this embodiment, since the positioning wall 113B for positioning the media sensor 116 is provided in the sub tank 113, the media sensor 116 is assembled to the front end plate with high positioning accuracy with respect to the front end plate 111. be able to.

  That is, since the media sensor 116 is positioned by the sub tank 113 assembled with high positioning accuracy with respect to the front end plate 111, the media sensor 116 can be assembled with high positioning accuracy with respect to the radiation port 111B.

  Further, since the radiation port 111B is provided in the front end plate 111 and the media sensor 116 is accommodated in the head unit casing 114, the media sensor 116 is disposed on the side surface of the front end plate. Compared with the front end plate, the width dimension of the front end plate 111 (the dimension of the portion parallel to the main scanning direction) can be reduced.

Therefore, according to the present embodiment, it is possible to reduce the width of the multi-function device 1 (printer unit 100) while improving the installation position accuracy of the media sensor 116.
In this embodiment, since the radiation port 111B is covered with the thin film 111C having water repellency, the thin film 111C covering the radiation port 111B is prevented while preventing the radiation port 111B from being blocked by ink. It is possible to suppress the ink from being attached. Therefore, it is possible to prevent a problem that the end of the recording sheet cannot be detected.

  In the present embodiment, since the thin film 111C is provided so as to cover the radiation port 111B from the platen 157 side, when viewed from the platen 157, the radiation port 111B has a flat shape with no depression. Therefore, since the surface tension of the ink attached to the thin film 111C can be reduced, the ink attached to the thin film 111C can be reliably made water repellent.

4). Correspondence between Invention Specific Items and Embodiments In this embodiment, the head unit 112 corresponds to the carriage described in the claims, and the thin film 111C corresponds to the film described in the claims.

(Second Embodiment)
In the first embodiment, the media sensor 116 (radiation port 111B) is arranged at the substantially center in the width direction of the front end plate 111 (head unit 112). However, in the present embodiment, as shown in FIGS. Further, a media sensor 116 (radiation port 111B) is arranged on the front side of the front end plate 111 and on one end side in the width direction.

14 is a perspective view of the head unit 112 according to the present embodiment, and FIG. 15 is a top view of the head unit casing 114 according to the present embodiment.
(Third embodiment)
In this embodiment, as shown in FIGS. 16 and 17, a part of the media sensor 116 in which the light emitting element and the light receiving element are accommodated, that is, the tip of the media sensor 116 is close to the front end plate 111 side. This is an example in which the present invention is applied to (a type with a short focal length).

  In the present embodiment, as shown in FIG. 17, the media sensor 116 is positioned in the horizontal direction by contacting the positioning wall 113B, and the protrusion provided on the positioning wall 113B in the vertical direction. Positioning is performed when the tip of the media sensor 116 contacts 113C.

  In this embodiment as well, as in the above-described embodiment, the head unit substrate 115 is fixed to the head unit casing 114 by being sandwiched between the sub tank 113 and the cap 114A. The dimensional variation up to the unit substrate 115 is absorbed by an elastic member such as a sponge disposed between the head unit substrate 115 and the cap 114A.

16 is a perspective view of the head unit substrate 115, and FIG. 17 is a cross-sectional view of the head unit 112 showing the media sensor 116 portion.
(Other embodiments)
In the above-described embodiment, the head unit casing 114 and the sub tank 113 are separate bodies. However, the present invention is not limited to this. For example, the head unit casing 114 and the sub tank 113 are integrally formed of resin. May be.

  In the above-described embodiment, the head unit casing 114, the front end plate 111, and the sub tank 113 are separate bodies, but the present invention is not limited to this, and the head unit casing 114, the front end plate 111, and the sub tank 113 may be integrally formed by die casting or the like. Good.

In the above-described embodiment, the thin film 111C is provided in the radiation port 111B. However, the present invention is not limited to this, and the thin film 111C may be eliminated.
In the above-described embodiment, the present invention is applied to a multi-function device, but the application of the present invention is not limited to this.

  Further, the present invention is not limited to the above-described embodiment as long as it matches the gist of the invention described in the claims.

1 is an external perspective view of a multi-function device 1 according to an embodiment of the present invention. 1 is a side view of a multi-function device 1 according to an embodiment of the present invention. 1 is a schematic diagram of a printer unit 100 according to an embodiment of the present invention. It is the figure which looked at the increfill unit 190, the image recording part 110, etc. from the upper surface side. It is the figure which looked at the head unit 112 which concerns on 1st Embodiment of this invention from the jet nozzle (nozzle) side. It is the external appearance perspective view which looked at the head unit (carriage) 112 which concerns on 1st Embodiment of this invention from the ejection outlet side. 4 is a top view showing a state in which a cap 114A and a head unit substrate 115 are removed from a head unit casing 114. FIG. It is AA sectional drawing of FIG. FIG. 3 is a side view of the head unit 112 according to the first embodiment of the present invention. FIG. 10 is a left side view (rear surface of the head unit 112) of FIG. 9; It is AA sectional drawing of FIG. It is BB sectional drawing of FIG. FIG. 3 is a perspective view of a head unit substrate 115 according to the first embodiment of the present invention. It is a perspective view of head unit 112 concerning a 2nd embodiment of the present invention. It is a top view of the head unit casing 114 which concerns on 2nd Embodiment of this invention. It is a perspective view of the head unit board | substrate 115 which concerns on 3rd Embodiment of this invention. It is sectional drawing of the head unit 112 which shows the media sensor 116 part in the head unit 112 which concerns on 3rd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Multifunctional device, 10 ... Operation panel, 20 ... Slot part, 30 ... Insertion port,
DESCRIPTION OF SYMBOLS 100 ... Printer part, 110 ... Image recording part, 111 ... Front end plate,
111A ... Jet, 111B ... Radiation port, 111C ... Thin film, 112 ... Head unit,
113 ... Sub tank, 113A ... Communication port, 113B ... Positioning wall,
113C ... Projection, 114 ... Head unit casing, 114A ... Cap,
115 ... Head unit substrate, 116 ... Media sensor, 150 ... Feeder unit,
151: Paper feed tray, 152: Separation inclined plate, 153: Paper discharge tray,
154 ... feed roller, 155 ... feed arm, 156 ... base shaft, 157 ... platen,
158 ... Rail member, 159 ... Driving roller, 160 ... Pressing roller,
161: paper discharge roller, 162: pressing roller, 190 ... ink refill unit,
191 ... Ink cartridge, 192 ... Ink tube, 200 ... Scanner part,
210: Document placement section, L1: Transfer path.

Claims (2)

An inkjet printer having a carriage that ejects ink droplets onto a recording medium, and a platen that is disposed opposite to the carriage with a predetermined gap to hold the recording medium,
The carriage is
A media sensor for detecting the edge of the recording medium by emitting light toward the platen side and detecting the reflected light;
A front end plate formed with an ejection port for ejecting ink droplets onto a recording medium and an emission port through which light emitted from the media sensor passes;
A tank that has a communication port that communicates with the ejection port side, and stores ink to be supplied to the ejection port;
The media sensor and the tank are accommodated, and the front end plate and a casing in which the tank is assembled are provided.
An ink jet printer, wherein the tank is provided with a positioning wall portion that contacts a part of the media sensor and positions the media sensor with respect to the radiation port.   The inkjet printer according to claim 1, wherein the radiation port is covered with a film having water repellency.

Images