Device for detecting floating of media in inkjet printer

Abstract

To enable floating of a medium positioned in a proceeding direction side of movement in a carriage not yet moved to be detected, when the carriage moves, and also enable floating of a medium positioned in the opposite direction side of the proceeding direction side of the movement in the carriage not yet moved to be detected.SOLUTION: A device for detecting floating of a medium in an inkjet printer comprises detection mechanisms arranged at one end part and the other end part respectively in a main scanning direction of a carriage. The detection mechanism has: a detection plate arranged with respect to the carriage with a preset interval from a medium; a pressurization mechanism that attracts the detection plate toward the carriage; a guide pin formed in the detection plate so that the pin protrudes toward the carriage; a concave part, formed at the carriage side, in which the guide pin is stored with a preset clearance opened and in which the detection plate is oscillatably arranged with the guide pin as a center; and detecting means that detects an inclination of the detection plate occurring when the detection plate is oscillates with the guide pin as the center.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a medium float detection device for an inkjet printer, and more particularly to an inkjet printer that uses an inkjet system to eject ink onto a medium to perform printing, and that detects medium float that can cause jams.

[0002] In this specification and the claims, the term "media" refers to not only various recording media made of paper such as plain paper, but also various flexible materials such as resin materials such as PVC and polyester, and materials such as aluminum, iron, and wood. Furthermore, in this specification and the claims, the term "inkjet method" refers to a printing method using inkjet technology by various conventionally known methods, including various continuous methods such as a binary deflection method or a continuous deflection method, and various on-demand methods such as a thermal method or a piezoelectric element method. [Background technology]

[0003] Generally, inkjet printers are known in which the overall operation is controlled by a computer system, and which have a platform on which a medium such as recording paper is placed, a carriage that can move in a predetermined direction above the medium placed on the platform, an ink head mounted on the carriage, and which use this ink head to print the desired image on the medium using an inkjet method. In this specification and claims, the direction in which the carriage moves in an inkjet printer will be referred to as the "main scanning direction" as appropriate. In the inkjet printers described above, the distance between the ink head and the medium is set to an extremely narrow distance, such as 1 mm to 2 mm, in order to improve printing accuracy and print quality. That is, in an inkjet printer, the ink head mounted on the carriage scans the medium in the main scanning direction at high speed with the extremely narrow spacing as the carriage moves at high speed in the main scanning direction.

[0004] Incidentally, it is known that in inkjet printers such as those described above, the medium may absorb ink and expand during printing, resulting in so-called paper lifting (medium lifting). It is known that such floating of the medium occurs in various parts of the medium, such as the edges and parts other than the edges. When such a medium float exists, even if the amount of the float is small, the gap between the ink head and the medium is so narrow that when the ink head or carriage comes into contact with the float, the medium gets caught in the underside or side of the ink head or carriage, which puts a load on the carriage that exceeds the carriage's transport force, making it impossible for the carriage to scan in the main scanning direction, often resulting in a jam.

[0005] Conventionally, inkjet printers have been provided with a float detection mechanism to prevent such jams from occurring, as disclosed in, for example, Japanese Patent Laid-Open Publication No. 9-39221, which detects floatation of the medium that can cause jams. Here, the floating detection mechanism disclosed in JP-A-9-39221 has a first floating detection mechanism provided at one end (left end) of a carriage that moves along a main scanning direction extending in the left-right direction in the main scanning direction, and a second floating detection mechanism provided at the other end (right end) of the carriage in the main scanning direction. The float detection mechanism disclosed in JP-A-9-39221 uses a first float detection mechanism to detect float of the medium when the carriage moves to the left along the main scanning direction, while a second float detection mechanism detects float of the medium when the carriage moves to the right along the main scanning direction. Therefore, the float detection mechanism disclosed in Japanese Patent Laid-Open No. 9-39221 can detect float of the medium that exists from the end of the carriage in the traveling direction toward the traveling direction.

[0006] However, the floating detection mechanism disclosed in JP-A-9-39221 had a problem in that, for example, when a medium floats past the first floating detection mechanism and becomes positioned on the underside of the carriage as the carriage moves to the left in the main scanning direction, or when a medium float originally occurred on the underside of the carriage before the carriage moved, the second floating detection mechanism was unable to detect such a medium float, resulting in a jam. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 9-39221 Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention has been made in consideration of the above-mentioned problems of the conventional technology, and its purpose is to provide a medium float detection device for an inkjet printer that, when the carriage moves in the inkjet printer, can detect float of a medium located on the side of the carriage in the direction of movement of the carriage before the movement, and can also detect float of a medium located on the side opposite to the direction of movement of the carriage before the movement. [Means for solving the problem]

[0009] In order to achieve the above-mentioned object, the medium float detection device in an inkjet printer according to the present invention has a first float detection mechanism provided at one end of a carriage moving along the main scanning direction in the main scanning direction, and a second float detection mechanism provided at the other end of the carriage in the main scanning direction, and each of the first float detection mechanism and the second float detection mechanism detects medium float located on the side of the carriage in the direction of movement and medium float located on the side opposite to the direction of movement. Therefore, with the medium float detection device in an inkjet printer according to the present invention, when the carriage moves, it becomes possible to detect the float of the medium located on the side of the carriage in the direction of movement before the movement, and it becomes possible to detect the float of the medium located on the opposite side of the carriage in the direction of movement before the movement.

[0010] In other words, the medium float detection device for an inkjet printer according to the present invention is an inkjet printer that has an ink head mounted on a carriage that is movable relative to the medium in the main scanning direction, and that prints by ejecting ink from the ink head onto the medium using an inkjet method, and has detection mechanisms arranged at one end and the other end of the carriage in the main scanning direction, and the detection mechanism has a detection plate that is arranged relative to the carriage at a predetermined distance from the medium, a pressure mechanism that attracts the detection plate toward the carriage, a guide pin formed on the detection plate so as to protrude toward the carriage, a recess formed on the carriage side that receives the guide pin with a predetermined clearance and positions the detection plate so that it can swing around the guide pin, and detection means that detects the inclination of the detection plate due to the detection plate swinging around the guide pin. In addition, the media float detection device for an inkjet printer according to the present invention is the same as the media float detection device for an inkjet printer according to the present invention described above, except that the detection plate is made of a soft material and is positioned opposite the media, and is formed so as to be bendable under a preset load. In addition, the media float detection device for an inkjet printer according to the present invention is the same as the media float detection device for an inkjet printer according to the present invention described above, except that the load that bends the detection plate is greater than the force that tilts the detection plate. In addition, the media float detection device for an inkjet printer according to the present invention is the media float detection device for an inkjet printer according to the present invention described above, in which the recess is provided in a convex-shaped member formed to protrude opposite the detection plate. Furthermore, the medium float detection device for an inkjet printer according to the present invention is the same as the medium float detection device for an inkjet printer according to the present invention described above, except that the guide pin has an approximately hemispherical shape and the recess has an approximately semi-cylindrical recess shape. In addition, the media float detection device for an inkjet printer according to the present invention is the same as the media float detection device for an inkjet printer according to the present invention described above, in which the outer diameter of the recess is larger than the outer diameter of the guide pin, and the recess depth is larger than the protruding height of the guide pin. Furthermore, the medium float detection device for an inkjet printer according to the present invention is the same as the medium float detection device for an inkjet printer according to the present invention described above, except that the clearance is set to 0.3 mm. Furthermore, the media float detection device for an inkjet printer according to the present invention is the same as the media float detection device for an inkjet printer according to the present invention described above, in which the pressure mechanism includes a biasing member, and the biasing force of the biasing member attracts the detection plate toward the carriage. Furthermore, the medium float detection device for an inkjet printer according to the present invention is the above-described medium float detection device for an inkjet printer according to the present invention, except that the biasing member is a spring or elastic body. Furthermore, the medium float detection device for an ink jet printer according to the present invention is the medium float detection device for an ink jet printer according to the present invention described above, except that the detection means is disposed above the detection plate on the carriage. Furthermore, the medium float detection device for an ink jet printer according to the present invention is the above-described medium float detection device for an ink jet printer according to the present invention, in which the detection means is a photosensor, a magnetic sensor or a limit switch. [Effects of the Invention]

[0011] Because the present invention is configured as described above, it has the excellent effect of being able to detect floating of a medium located on the side of the carriage in the direction of movement of the carriage before the movement when the carriage moves in an inkjet printer, and also being able to detect floating of a medium located on the side opposite to the direction of movement of the carriage before the movement. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a perspective view illustrating a configuration of an inkjet printer equipped with a medium float detection device according to an embodiment of the present invention. [Figure 2] FIG. 2 is a perspective view illustrating the inkjet printer shown in FIG. 1 with an exterior member removed. [Figure 3] FIG. 3 is a cross-sectional view illustrating the vertical cross section of the inkjet printer shown in FIG. [Figure 4]FIG. 4 is a diagram showing a schematic configuration of a medium float detection device in an inkjet printer according to an embodiment of the present invention, as viewed from the arrow A (front view) in FIG. [Figure 5] FIG. 5 is a diagram showing a schematic configuration of a medium float detection device in an inkjet printer according to an embodiment of the present invention, as viewed from the arrow B in FIG. 2 (left side view). [Figure 6] Figure 6 is a schematic diagram illustrating the left detection mechanism, which is the first detection mechanism constituting the medium float detection device in an inkjet printer according to an embodiment of the present invention, viewed from the arrow A (front view) in Figure 2, with some of the components broken away. [Figure 7] Figure 7 is a schematic diagram illustrating the configuration of the left detection mechanism, which is the first detection mechanism constituting the medium float detection device in an inkjet printer according to an embodiment of the present invention, viewed from the arrow C (left side view) in Figure 6, focusing on the detection plate. [Figure 8] FIG. 8 is a diagram illustrating the configuration of the left outer lower end portion of the carriage as viewed from the arrow C in FIG. 6 (left side view). [Figure 9] Fig. 9(a) is a structural explanatory view that schematically shows the cross-sectional structure taken along line DD in Fig. 7. Fig. 9(b) is an exploded structural explanatory view of Fig. 9(a). [Figure 10] Fig. 10(a) is a structural explanatory diagram that schematically shows the cross-sectional structure taken along line EE and line FF in Fig. 7. Fig. 10(b) is an exploded structural explanatory diagram of Fig. 10(a). [Figure 11] FIG. 11 is an explanatory diagram illustrating the operation of an inkjet printer equipped with a medium float detection device according to an embodiment of the present invention during printing (a state in which medium float is not detected). [Figure 12] FIG. 12 is an explanatory diagram illustrating the operation of an inkjet printer equipped with a medium float detection device according to an embodiment of the present invention during printing (a state in which medium float is detected). [Figure 13]FIG. 13 is an explanatory diagram illustrating the operation of an inkjet printer equipped with a medium float detection device according to an embodiment of the present invention during printing (a state in which medium float is detected). DETAILED DESCRIPTION OF THE INVENTION

[0013] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a medium float detection device for an inkjet printer according to the present invention will be described in detail below with reference to the accompanying drawings.

[0014] (I) Description of the overall configuration of an inkjet printer equipped with a medium float detection device in an inkjet printer according to the present invention

[0015] In the following description, the Y direction in the XYZ Cartesian coordinate system indicates the main scanning direction, which is the direction of movement of carriage 20 (described later), the X direction in the XYZ Cartesian coordinate system indicates the sub-scanning direction, which is the direction perpendicular to the Y direction (main scanning direction) in the XY plane, and the Z direction in the XYZ Cartesian coordinate system indicates the height direction perpendicular to the XY plane. Furthermore, in the following explanation, for the sake of convenience, the left side of the paper on which Figure 1 is drawn will be referred to as the left direction and the right side will be referred to as the right direction in the Y direction (main scanning direction), the lower side of the paper on which Figure 1 is drawn will be referred to as the front direction and the upper side will be referred to as the rear direction in the X direction (sub-scanning direction), and the lower side of the paper on which Figure 1 is drawn will be referred to as the down direction and the upper side will be referred to as the up direction in the Z direction (height direction). It should be noted that the directions described above are merely defined for the convenience of explanation, and do not in any way limit the manner in which the inkjet printer may be installed, nor do they in any way limit the present invention.

[0016] Reference numeral 10 denotes a so-called flatbed type inkjet printer, and this inkjet printer 10 prints images and the like by ejecting ink from an ink head 22 onto a medium 12 using an inkjet method. More specifically, the inkjet printer 10 has a base 14 that is rectangular in the XY plane, an exterior member 16 that is arranged on the base 14 so as to cover the base 14 from above, leaving a predetermined area of ​​space A, a rectangular plate-like mounting table 18 that is movable in the X direction (sub-scanning direction) and the Z direction (height direction) within the space A and so that its upper surface 18a is parallel to the XY plane, a carriage 20 that is arranged above the mounting table 18 within the space A so as to be movable in the Y direction (main scanning direction), an ink head 22 mounted on the carriage 20, a left detection mechanism 100L that is a first detection mechanism that is arranged at the left outer lower end 20L of the carriage 20, and a right detection mechanism 100R that is a second detection mechanism that is arranged at the right outer lower end 20R of the carriage 20. The medium 12 to be printed by the inkjet printer 10 is placed at an appropriate position on the upper surface 18a of the table 18.

[0017] Here, the medium float detection device in an inkjet printer according to the present invention is configured to include the left detection mechanism 100L and the right detection mechanism 100R described above. The carriage 20 is covered by a carriage cover 20a, and the ink head 22 is mounted on the carriage 20 while being covered by the carriage cover 20a. As will be described later, the carriage 20 is configured to be movable relative to the mounting table 18 in the Y direction (main scanning direction), the X direction (sub-scanning direction), and the Z direction (height direction).

[0018] Such inkjet printer 10 is equipped with a computer system (not shown), and the user can control the overall operation of inkjet printer 10 through the computer system by operating various controls provided on operation panel 24 located at the top right end of exterior member 16.

[0019] That is, although detailed illustration is omitted, the operation panel 24 is provided with operators that allow the user to perform various operations such as setting operations and input operations related to image printing, as well as a display unit that displays the operation status of the operators. Specifically, the display unit displays information related to printing, such as the type of printing, resolution, printing status, and printing area settings. Further, as operation devices, for example, a switch for turning on / off the power supply of the inkjet printer 10, input buttons for setting information relating to printing, and the like are arranged.

[0020] Here, the exterior member 16 has a box-like shape with an open bottom, and is provided with an openable and closable cover member 26 at the front portion. The exterior member 16 is detachably attached to the base portion 14 at its lower portion.

[0021] More specifically, the inkjet printer 10 has a frame 28 disposed on the base 14 above the mounting table 18 and extending in the Y direction (main scanning direction). A guide rail 30 extending along the Y direction (main scanning direction) is provided on the front surface of the frame 28, and the carriage 20 is engaged with this guide rail 30 so as to be slidable in the Y direction (main scanning direction).

[0022] Here, the inkjet printer 10 is configured to allow the carriage 20 to move back and forth along the Y direction (main scanning direction) on the guide rail 30, and includes a left pulley 32 located to the left of the left end of the guide rail 30, a right pulley 34 located to the right of the right end of the guide rail 30, an endless belt 36 wound around the left pulley 32 and the right pulley 34, and a motor 38 connected to the right pulley 34 and rotating the right pulley 34. The carriage 20 is fixed to a predetermined location on the belt 36, and when the motor 38 is driven to rotate the right pulley 34, the belt 36 runs between the left pulley 32 and the right pulley 34, causing the carriage 20 fixed to the belt 36 to move in the Y direction (main scanning direction).

[0023] In this embodiment, the ink head 22 is disposed inside the carriage 20 with the nozzles that eject ink toward the medium 12 by ink jet method positioned downward. The lower portion of the carriage 20 is open so as not to obstruct the ejection of ink from the nozzles of the ink head 22 toward the medium 12 .

[0024] Next, the inkjet printer 10 is provided with the mounting table 18 on which the medium 12 is placed as described above, and this mounting table 18 is formed of a plate-like body extending along the XY plane. Regarding the positional relationship between the mounting table 18 and the ink head 22 in the Z direction (height direction), the mounting table 18 is disposed below the nozzles of the ink head 22.

[0025] Here, the inkjet printer 10 is equipped with a sub-scanning direction movement mechanism 40 that moves the mounting table 18 in the X direction (sub-scanning direction), and a height direction movement mechanism 42 that moves the mounting table 18 in the Z direction (height direction).

[0026] The sub-scanning direction movement mechanism 40 is housed within the base 14 and includes a right slide rail 44R that extends in the X direction (sub-scanning direction) and is attached to the base 14, a left slide rail (not shown) that extends in the X direction (sub-scanning direction) parallel to the right slide rail 44R and is attached to the base 14, a support member 46 that is slidably engaged with and guided by the right slide rail 44R and the left slide rail and is capable of reciprocating movement in the X direction (sub-scanning direction), and a support member movement motor (not shown) connected to the support member 46. The support member 46 is formed in a box shape, and has an opening 46a that opens upward. Therefore, according to the sub-scanning direction movement mechanism 40, when the support member movement motor is driven to rotate, the support member 46 is moved in the X direction (sub-scanning direction) along the right slide rail 44R and the left slide rail.

[0027] Next, the above-mentioned height-direction movement mechanism 42 is housed within the support member 46 and is configured to include a plurality of guide posts 48 extending in the Z direction (height direction), a box-shaped mounting platform support case 50 that is slidably engaged with the guide posts 48 and guided by them so as to be able to move back and forth in the Z direction (height direction), and a mounting platform support case movement motor (not shown) connected to the mounting platform support case 50. The mounting table 18 is fixed to the top surface of the mounting table support case 50 and is supported by the mounting table support case 50 . Therefore, according to the height direction movement mechanism 42, the mounting table support case 50 is moved in the Z direction (height direction) along the guide support posts 48 by driving and rotating the mounting table support case movement motor.

[0028] (II) Detailed Description of the Configuration of the Medium Float Detection Device in an Inkjet Printer According to the Present Invention As described above, the medium float detection device in an inkjet printer according to the present invention is configured to include a left detection mechanism 100L, which is a first detection mechanism arranged at the left outer lower end 20L of the carriage 20, and a right detection mechanism 100R, which is a second detection mechanism arranged at the right outer lower end 20R of the carriage 20.

[0029] The left detection mechanism 100L and the right detection mechanism 100R are configured such that their constituent members are arranged symmetrically with respect to the left outer lower end 20L and the right outer lower end 20R of the carriage 20, respectively. Therefore, in the following explanation, we will provide a detailed explanation of the left detection mechanism 100L, and for the right detection mechanism 100R, we will appropriately omit detailed explanations by changing the ``L'' in the symbols attached to each component when explaining the left detection mechanism 100L to ``R'' and attaching it to each component.

[0030] Here, the left detection mechanism 100L is arranged opposite the left outer lower end 20L of the carriage 20 (for the right detection mechanism 100R, it is the right outer lower end 20R of the carriage 20), and is equipped with a detection plate 102L that can be arranged to extend perpendicular to the XY plane in the Z direction. This detection plate 102L is composed of a base plate 104L formed from a rigid metal body having an approximately flat plate shape, and a detection plate 106L having an approximately flat plate shape formed from a soft material such as rubber so as not to damage the medium 12 when it comes into contact with the medium 12.

[0031] Here, the detection plate 106L is positioned opposite the medium 12 placed on the upper surface 18a of the mounting table 18 in the Z direction, and its dimensions are set so that it is positioned at a predetermined distance from the medium 12.

[0032] In addition, the upper end of this base plate 104L is bent so that when the detection plate 102L is positioned so as to extend perpendicularly in the Z direction relative to the XY plane, a reflective portion 104La is formed, which is an area extending parallel to the XY plane.

[0033] Here, as described above, the detection plate 106L is made of a soft material such as rubber, and is configured to bend and release the force when a load exceeding a certain level is applied according to the soft material, thereby preventing damage to the medium 12 when the detection plate 106L presses the float 12a of the medium 12 (see Figures 12 and 13). Furthermore, the load that bends the detection plate 106L is preferably set to be greater than the force that is applied when the detection plate 106L presses against the float 12a of the medium 12 (see Figures 12 and 13), causing the detection plate 102L to rotate.

[0034] The operation of the detection plate 106L pushing the float 12a of the medium 12 (see FIGS. 12 and 13), resulting in the rotation of the detection plate 102L, will be described in detail later with reference to FIGS.

[0035] On the other hand, above the reflecting portion 104La, a photosensor 108L is disposed as a detection means. More specifically, the photosensor 108L is attached to the left outer lower end 20L of the carriage 20 (the photosensor 108R is attached to the right outer lower end 20R of the carriage 20). The photosensor 108L is provided with a light-emitting portion 108La that emits light, and a light-receiving portion 108Lb that can receive reflected light of the light (emitted light) emitted from the light-emitting portion 108La.

[0036] Here, the detection plate 102L and the photosensor 108L are arranged at the left outer lower end 20L of the carriage 20 so that the detection plate 102L extends perpendicular to the Z direction relative to the XY plane, and when the reflecting portion 104La is positioned extending parallel to the XY plane, the reflecting portion 104La reflects the light (emitted light) emitted from the light emitting portion 108La, and the reflected light, which is the light received by the light receiving portion 108Lb, is received. That is, when the reflecting portion 104La is positioned extending parallel to the XY plane, the reflecting portion 104La can reflect the light (emitted light) emitted from the light-emitting portion 108La toward the light-receiving portion 108Lb, and the light-receiving portion 108Lb can receive the reflected light; on the other hand, when the reflecting portion 104La is not positioned extending parallel to the XY plane, the reflecting portion 104La cannot reflect the light (emitted light) emitted from the light-emitting portion 108La toward the light-receiving portion 108Lb, and the light-receiving portion 108Lb cannot receive the reflected light.

[0037] In this embodiment, in the photosensor 108L, a state in which the light receiving unit 108Lb receives reflected light of the light (emitted light) emitted from the light emitting unit 108La is considered to be OFF (OFF: a state in which the float 12a of the medium 12 is not detected), and a state in which the light receiving unit 108Lb does not receive light emitted from the light emitting unit 108La is considered to be ON (ON: a state in which the float 12a of the medium 12 is detected).

[0038] Furthermore, the photosensor 108L described above can be configured by applying conventionally known techniques, and therefore detailed description thereof will be omitted.

[0039] Next, referring mainly to Figures 6, 7, 8 and 9(a)(b), we will explain how to attach the base plate 104L to the carriage 20. A carriage mounting pin 110L that protrudes toward the carriage 20 is formed at approximately the center of the base plate 104L in the XZ plane. On the other hand, a wall surface 20La of the left outer lower end portion 20L of the carriage 20 is formed with a through-hole 20Lb through which the carriage mounting pin 110L can be inserted with a preset gap.

[0040] The base plate 104L is secured to the wall surface 20La by inserting the carriage mounting pin 110L from the left side to the right side into the through hole 20Lb, and the carriage mounting pin 110L is inserted into the through hole 20Lb, and furthermore, a coil spring 112L, which is a biasing member and has a biasing force in the extension direction, is inserted into the carriage mounting pin 110L.

[0041] Here, reference numeral 114L denotes a washer, which is fixed to the end face of the tip end (right end) of the carriage attachment pin 110L by a screw 116L. The coil spring 112L is disposed with a preset biasing force in the extension direction, with the right end 112La in contact with the washer 114L and the left end 112Lb in contact with the wall surface 20La.

[0042] Therefore, by inserting the pin 110 of the base plate 104L into the through hole 20Lb, then inserting the coil spring 112L into the pin 110, and then fixing the washer 114L to the end face of the tip end (right end) of the carriage mounting pin 110L with a screw 116L, the base plate 104L is always attracted and pressed toward the carriage 20 by a preset biasing force. That is, the left detection mechanism 100L includes a pressure applying mechanism that constantly attracts the base plate 104L of the detection plate 102L toward the carriage 20 side by the biasing force of the coil spring 112L.

[0043] Next, referring mainly to Figures 6, 7, 8 and 10(a)(b), we will explain how to attach the base plate 104L to the carriage 20.On the front and rear sides of the carriage attachment pin 110L of the base plate 104L in the X direction (sub-scanning direction), guide pins 120L are formed, each of which protrudes toward the carriage 20 and has an approximately hemispherical shape. On the other hand, a base block 122 is provided on the wall surface 20La of the left outer lower end portion 20L of the carriage 20, with a recess 122a having an approximately semi-cylindrical recessed shape that can accommodate a guide pin 120L by opening a predetermined clearance (gap).

[0044] This base block 122 is a convex-shaped member formed to protrude opposite the base plate 104L of the detection plate 102L, and the area around the recess 122a in the base block 122 is formed as a flat portion 122b having a plane parallel to the XZ plane.

[0045] Here, the base plate 104L of the detection plate 102L is attracted toward the carriage 20 by the biasing force of the coil spring 112L in the above-mentioned pressure mechanism, and as a result, the guide pin 120L is housed in the recess 122a. At this time, the flat portion 124L having a plane parallel to the XZ plane on the surface of the base plate 104L facing the carriage 20 abuts against the flat portion 122b of the base block 122, and a predetermined clearance (gap) is opened and the guide pin 120L is accommodated in the recess 122a.

[0046] The above-mentioned clearance (gap) is set, for example, so that the outer diameter β of the recess 122a of the base block 122 is larger than the outer diameter α of the guide pin 120L (α<β), and the recess depth δ of the recess 122a of the base block 122 is larger than the protruding height γ of the guide pin 120L (γ<δ). Specifically, the dimensions of the guide pin 120L and the recess 122a may be set so that when the guide pin 120L is accommodated in the recess 122a by the above-mentioned pressurizing mechanism, a clearance (gap) of, for example, about 0.3 mm is formed.

[0047] (III) Description of the operation of the medium float detection device in the inkjet printer according to the present invention

[0048] In the inkjet printer 10, printing is performed on the medium 12 while the carriage 20 is moved back and forth left and right in the Y direction (main scanning direction). At this time, the detection plate 102L attached to the carriage 20 may oscillate in the direction of arrow G (see Figure 11) around the guide pin 120L due to acceleration and vibrations during movement of the carriage 20 or vibrations received by the entire inkjet printer 10, and may become tilted from a position perpendicular to the XY plane.

[0049] However, as explained above, the left detection mechanism 100L is equipped with a pressure mechanism that constantly pulls the base plate 104L of the detection plate 102L toward the carriage 20 by the biasing force of the coil spring 112L, thereby significantly suppressing the oscillation of the detection plate 102L in the direction of arrow G due to the acceleration operation and vibration described above. Therefore, in the inkjet printer 10, during the printing operation in which printing is performed on the medium 12 while the carriage 20 is moved back and forth in the Y direction (main scanning direction), as shown in Figure 11, the flat portion 124L of the base plate 104L and the flat portion 122b of the base block 122 abut against each other, a predetermined clearance (gap) is opened and the guide pin 120L is housed in the recess 122a, the detection plate 102L is in a vertical position with respect to the XY plane, and the reflecting portion 104La is in a horizontal position with respect to the XY plane. In this state, the photosensor 108L is in an OFF state in which the light receiving portion 108Lb receives reflected light of the light (emitted light) emitted from the light emitting portion 108La.

[0050] However, as shown in Figure 12, if there is a floating portion 12a on the medium 12 when the carriage 20 is moving leftward in the Y direction (main scanning direction), the floating portion 12a on the medium 12 will relatively push the detection plate 106L of the detection plate 102L to the right in the Y direction (main scanning direction). As a result, detection plate 102L rotates in the direction of arrow H around guide pin 120L and tilts from a position perpendicular to the XY plane.

[0051] Here, even if the detection plate 102L rotates in the direction of arrow H and tilts from a position perpendicular to the XY plane, the guide pin 120L is housed in the recess 122a of the base block 122, so the detection plate 102L tilts without causing misalignment.Furthermore, since the guide pin 120L is set so that a predetermined clearance (gap) opens when it is housed in the recess 122a, the guide pin 120L can move smoothly within the recess 122a without getting caught on or gouging the recess 122a, even if the detection plate 102L tilts.

[0052] In this way, when the force with which the float 12a of the medium 12 pushes the detection plate 106L of the detection plate 102L to the right in the Y direction (main scanning direction) becomes greater than the force with which it is pulled toward the carriage 20 by the above-mentioned pressure mechanism, the detection plate 102L rotates in the direction of arrow H, and the detection plate 102L tilts from a vertical position relative to the XY plane, and the reflecting portion 104La tilts from a horizontal position relative to the XY plane.

[0053] In this state, the photosensor 108L is in an ON state because the light receiving section 108Lb cannot receive the reflected light of the light (emitted light) emitted from the light emitting section 108La, and thus the floating 12a of the medium 12 can be detected. That is, the photosensor 108L detects the inclination of the detection plate 102, thereby making it possible to detect the floating 12a of the medium 12.

[0054] Also, as shown in Figure 13, if there is a floating portion 12a on the medium 12 when the carriage 20 is moving to the right in the Y direction (main scanning direction), the floating portion 12a on the medium 12 will relatively push the detection plate 106L of the detection plate 102L to the left in the Y direction (main scanning direction). As a result, detection plate 102L rotates in the direction of arrow I around guide pin 120L and tilts from a position perpendicular to the XY plane.

[0055] Here, even if the detection plate 102L rotates in the direction of arrow I and tilts from a position perpendicular to the XY plane, the guide pin 120L is housed in the recess 122a of the base block 122, so the detection plate 102L tilts without causing misalignment, and since the guide pin 120L is set so that a predetermined clearance (gap) opens when it is housed in the recess 122a, even if the detection plate 102L tilts, the guide pin 120L can move smoothly within the recess 122a without getting caught on or gouging the recess 122a.

[0056] In this way, when the force with which the floating 12a of the medium 12 pushes the detection plate 106L of the detection plate 102L to the left in the Y direction (main scanning direction) becomes greater than the force with which it is pulled toward the carriage 20 by the above-mentioned pressure mechanism, the detection plate 102L rotates in the direction of arrow I, and the detection plate 102L tilts from a vertical position with respect to the XY plane, and the reflecting portion 104La tilts from a horizontal position with respect to the XY plane.

[0057] In this state, the photosensor 108L is in an ON state because the light receiving section 108Lb cannot receive the reflected light of the light (emitted light) emitted from the light emitting section 108La, and thus the floating 12a of the medium 12 can be detected. That is, the photosensor 108L detects the inclination of the detection plate 102, thereby making it possible to detect the floating 12a of the medium 12.

[0058] Therefore, the left detection mechanism 100L can detect the floating 12a of the medium 12 when the carriage 20 moves left or right in the Y direction (main scanning direction).

[0059] In addition, the right-hand detection mechanism 100R also performs the same operation as the left-hand detection mechanism 100L described above, and can detect the floating 12a of the medium 12 regardless of whether the carriage 20 moves left or right in the Y direction (main scanning direction).

[0060] (IV) Explanation of the operation and effect of the medium float detection device in the inkjet printer according to the present invention As described above, the medium float detection device in the inkjet printer 10 of the present invention, which is configured to have the left detection mechanism 100L and the right detection mechanism 100R, can detect the float 12a of the medium 12 located in the direction of movement of the carriage 20 before the movement when the carriage 20 moves in the inkjet printer 10, and can also detect the float 12a of the medium 12 located in the opposite direction to the direction of movement of the carriage 20 before the movement.

[0061] (V) Description of Other Embodiments and Modifications The above-described embodiments are merely examples, and the present invention can be embodied in various other forms. That is, the present invention is not limited to the above-described embodiments, and various omissions, substitutions, modifications, etc. can be made within the scope of the gist of the present invention. For example, the above-described embodiment may be modified as shown in the following (V-1) to (V-12).

[0062] (V-1) In the above embodiment, a coil spring is used as the biasing member that constitutes the pressurizing mechanism. However, it goes without saying that the biasing member that constitutes the pressurizing mechanism is not limited to a coil spring. That is, the biasing member constituting the pressurizing mechanism may be, for example, a spring such as a leaf spring or a helical spring, or an elastic body such as rubber, and may be appropriately selected and used depending on the design conditions, etc.

[0063] (V-2) In the above embodiment, the photo sensor is attached to the carriage as the detection means, but the location where the photo sensor is attached is not limited to the carriage. That is, as long as the tilt of the detection plate can be detected, the photosensor may be attached at an appropriate location selected according to design conditions and the like.

[0064] (V-3) In the above embodiment, a photo sensor is used as the detection means, but it goes without saying that the detection means is not limited to a photo sensor. That is, the detection means may be, for example, a magnetic sensor or a limit switch, which may be appropriately selected according to design conditions.

[0065] (V-4) In the above embodiment, the base plate is made of a rigid metal body and the detection plate is made of a soft material, but it goes without saying that the present invention is not limited to this. That is, the materials for forming the base plate and the detection plate may be appropriately selected according to the design conditions and the like.

[0066] (V-5) In the above embodiment, the detection plate is configured using two members, the base plate and the detection plate, but it goes without saying that this is not limitative. That is, the detection plate may be made up of a single member, or may be made up of three or more members. The material for forming the detection plate may be selected appropriately depending on the design conditions.

[0067] (V-6) In the above embodiment, the carriage and the base block are constructed as separate bodies, and the base block is disposed relative to the carriage, but it goes without saying that the present invention is not limited to this. For example, when forming the carriage, the base block may be integrally molded onto the wall surface in advance.

[0068] (V-7) In the above embodiment, the recess 122a has been described as having an approximately semi-cylindrical recess shape, but it goes without saying that the shape of the recess 122a is not limited to this, and for example, the recess 122a may have an approximately hemispherical recess shape.

[0069] (V-8) In the above embodiment, the case where the carriage moves in the Y direction (main scanning direction) relative to the mounting table has been described, but it is needless to say that the present invention is not limited to this. For example, the mounting table may move in the Y direction (main scanning direction) relative to the carriage, or both the carriage and the mounting table may move in the Y direction (main scanning direction). In short, it is sufficient to have a configuration in which the carriage and the medium are relatively movable in the Y direction (main scanning direction).

[0070] (V-9) In the above embodiment, the case where the mounting table 18 is moved relative to the carriage 20 in the X direction (sub-scanning direction) has been described, but it goes without saying that this is not limited to this. For example, the mounting table 18 may be fixed in the X direction (sub-scanning direction), and the carriage 20 may be configured to be movable relative to the mounting table 18 in the Y direction (main scanning direction) and the X direction (sub-scanning direction).

[0071] (V-10) In the above embodiment, the case where the mounting table 18 is moved relative to the carriage 20 in the Z direction (height scanning direction) has been described, but it goes without saying that this is not limited to this. For example, the mounting table 18 may be fixedly installed in the Z direction (height scanning direction), and the carriage 20 may be configured to be movable relative to the mounting table 18 in the Z direction (height scanning direction).

[0072] (V-11) In the above embodiment, the inkjet printer has been described as a so-called flatbed type inkjet printer 10, but it goes without saying that the inkjet printer is not limited to this. Other inkjet printers include so-called paper-move type inkjet printers, such as roll-to-roll type inkjet printers that print while transporting a rolled medium in the X direction (sub-scanning direction), and the present invention may be applied to such inkjet printers.

[0073] (V-12) It goes without saying that the above-described embodiment and the various other embodiments and modifications shown in (V-1) to (V-11) above may be combined as appropriate. [Industrial Applicability]

[0074] The present invention is suitable for use in an inkjet printer that performs printing by ejecting ink onto a medium using an inkjet method. [Explanation of symbols]

[0075] 10. Inkjet printer 12 Medium 12a Float 14 Base 16 Exterior materials 18 Mounting table 18a Top side 20 carriages 20a Carriage cover 20L Left outer lower end 20La wall 20Lb through hole (pressurization mechanism) 20R Right outer lower end 22 Ink head 24 Operation Panel 26 Cover member 28 frames 30 guide rail 32 Left pulley 34 Right pulley 36 Belt 38 Motor 40 Sub-scanning direction movement mechanism 42 Height movement mechanism 44R right slide rail 46 Support member 46a opening 48 Guide Post 50 Mounting table support case 100L Left detection mechanism (first detection mechanism) (detection mechanism) 100R Right detection mechanism (second detection mechanism) (detection mechanism) 102L Detection plate 102R detection plate 104L base plate 104R base plate 104La Reflector 104Ra Reflector 106L Detection Plate 106R Detection Plate 108L Photo sensor (detection means) 108La Light-emitting unit (detection means) 108Lb light receiving unit (detection means) 108R Photo sensor (detection means) 108Ra Light emitting unit (detection means) 108Rb Light receiving unit (detection means) 110L Carriage mounting pin (pressure mechanism) 112L Coil spring (pressure mechanism) (biasing member) 114L washer (pressurization mechanism) 116L screw (pressurization mechanism) 120L Guide Pin 122 Base block (convex-shaped member) 122a Recess 122b Flat part 124L flat part A Space α Outer diameter of guide pin β Outer diameter of the recess in the base block γ Guide pin protrusion height δ Depth of the recess in the base block

Claims

1. 1. A medium float detection device for an inkjet printer that includes an ink head mounted on a carriage that is movable relative to a medium in a main scanning direction, and that performs printing by ejecting ink from the ink head onto the medium using an inkjet method, a detection mechanism disposed at each of one end and the other end of the carriage in the main scanning direction; The detection mechanism includes: a detection plate disposed relative to the carriage at a predetermined interval from the medium; a pressurizing mechanism that attracts the detection plate toward the carriage; a guide pin formed on the detection plate so as to protrude toward the carriage; a recess formed on the carriage side, the recess accommodating the guide pin with a predetermined clearance, and the detection plate being disposed around the guide pin so as to be swingable; a detection means for detecting the tilt of the detection plate caused by the detection plate swinging around the guide pin; 1. A medium float detection device for an inkjet printer, comprising:

2. 2. The device for detecting a medium float in an inkjet printer according to claim 1, The detection plate is made of a flexible material and is disposed opposite the medium, and has a detection plate formed to be bendable under a preset load.

1. A device for detecting floating of a medium in an inkjet printer.

3. 3. The device for detecting a medium float in an inkjet printer according to claim 2, The load that bends the detection plate is greater than the force that tilts the detection plate.

1. A device for detecting floating of a medium in an inkjet printer.

4. 4. The device for detecting a medium float in an inkjet printer according to claim 1, 2 or 3, The recess is provided in a convex member formed to protrude opposite the detection plate.

1. A device for detecting floating of a medium in an inkjet printer.

5. 5. The device for detecting a medium float in an inkjet printer according to claim 1, wherein: The guide pin has a generally hemispherical shape, The recess has a substantially semi-cylindrical recess shape.

1. A device for detecting floating of a medium in an inkjet printer.

6. 6. The device for detecting a medium float in an inkjet printer according to claim 5, The outer diameter of the recess is larger than the outer diameter of the guide pin, The recess depth of the recess is greater than the protruding height of the guide pin.

1. A device for detecting floating of a medium in an inkjet printer.

7. 7. The device for detecting a floating of a medium in an inkjet printer according to claim 1, wherein The clearance is 0.3 mm.

1. A device for detecting floating of a medium in an inkjet printer.

8. 8. The device for detecting a floating of a medium in an inkjet printer according to claim 1, wherein the pressure applying mechanism includes a biasing member; The biasing force of the biasing member attracts the detection plate toward the carriage.

1. A device for detecting floating of a medium in an inkjet printer.

9. 9. The device for detecting a medium float in an inkjet printer according to claim 8, The biasing member is a spring or an elastic body.

1. A device for detecting floating of a medium in an inkjet printer.

10. 10. The device for detecting a floating of a medium in an inkjet printer according to claim 1, wherein The detection means is disposed above the detection plate on the carriage.

1. A device for detecting floating of a medium in an inkjet printer.

11. 11. The device for detecting a floating of a medium in an inkjet printer according to claim 1, wherein The detecting means is a photo sensor, a magnetic sensor, or a limit switch.

1. A device for detecting floating of a medium in an inkjet printer.

Images