Roll media holding device and image forming apparatus

Abstract

To provide a roll medium holding device for holding a roll medium by accurately positioning at a prescribed position.SOLUTION: A roll medium holding device comprises: a medium positioning part having an inclined surface with which a side end of a roll medium is in contact; and a medium holding part which is held rotatably with an axis parallel to a rotation axis of the roll medium as a rotation center, and further can move in a radial direction of the roll medium, and is held by being energized from the rotation axis of the roll medium toward an inner peripheral surface of the roll medium.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a roll media holding device and an image forming apparatus. [Background technology]

[0002] A roll media holding device is known that holds continuous sheet media (hereinafter referred to as "media") so that the media can be transported from the rolled media. Also known is an image forming apparatus that includes a roll media holding device, forms an image on the transported media, and has a media winding device disposed opposite the roll media holding device.

[0003] Roll media is formed by wrapping the media around a hollow cylindrical core. A known technology for conventional roll media holding devices is to include an expansion abutment member that expands radially in response to the inner diameter of the roll media (the inner diameter of the core), and expand the expansion abutment member to hold the roll media (see Patent Document 1). Summary of the Invention [Problem to be solved by the invention]

[0004] The technology described in Patent Document 1 uses an L-shaped leaf spring in the structure (holding portion) that holds the roll media. This leaf spring does not function to position the roll media. Therefore, when using the technology described in Patent Document 1, the axial position of the roll media is prone to variation due to the expansion abutment member. Furthermore, the leaf spring described in Patent Document 1 is insufficient to hold the roll media in a predetermined position because its only movable direction is the radial direction of the roll media. Therefore, conventional technology has issues with positioning and holding the roll media in a predetermined position.

[0005] An object of the present invention is to provide a roll media holding device that accurately positions and holds roll media at a predetermined position. [Means for solving the problem]

[0006] In order to solve the above technical problem, one aspect of the present invention is a method for holding a roll medium in a rotatable manner. A roll media holding device having an inclined surface that contacts the side edge of the roll media. The media positioning unit rotates around an axis parallel to the rotation axis of the roll media. The roll medium is held in a radial direction of the roll medium and is movable in the radial direction of the roll medium. The media holder is biased from the rotation axis of the media toward the inner peripheral surface of the roll media and holds the media. With a holding part, The media holding section has a contact member that contacts the roll media, a fixed member that is positioned symmetrically with respect to a support shaft that supports the contact member, and an elastic member that has one end fixed to the contact member and the other end fixed to the fixed member, and the elastic members are configured as a pair that sandwich the support shaft, and each of the elastic members urges the end of the contact member radially outward from the inner circumferential surface of the roll media. It is characterized by: [Effects of the Invention]

[0007] According to the present invention, the roll medium can be positioned and held at a predetermined position with high precision. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a partially perspective perspective view of a schematic configuration of an image forming apparatus according to an embodiment of the present invention; [Figure 2] FIG. 1 is a schematic side view of an image forming apparatus according to an embodiment of the present invention. [Figure 3] FIG. 2 is a partial perspective plan view of an image forming unit included in the image forming apparatus according to the embodiment. [Figure 4] 1 is a side view of a roll body holding device according to an embodiment of the roll media holding device of the present invention; [Figure 5] FIG. 3 is a rear view of the roll body holding device. [Figure 6] FIG. 3 is a side view illustrating a core holding device provided in the roll body holding device. [Figure 7] FIG. 3 is a front cross-sectional view of a core holding device included in the roll body holding device. [Figure 8] FIG. 2 is an illustrative side view according to the first embodiment of a medium holding member included in the roll holding device. [Figure 9] FIG. 2 is a front cross-sectional view of the medium holding member according to the first embodiment. [Figure 10] FIG. 10 is an illustrative side view of a second embodiment of a medium holding member included in the roll body holding device. [Figure 11] FIG. 10 is a front cross-sectional view of the medium holding member according to a second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. First, an inkjet printer 100, which is an embodiment of an image forming apparatus equipped with a roll media holding device according to the present invention, will be described with reference to FIGS. 1 to 3. FIG. 1 is a perspective view illustrating the exterior of the inkjet printer 100. FIG. 2 is a schematic diagram showing a side view of the inkjet printer 100. FIG. 3 is a plan view showing the main parts of an image forming unit 104 equipped in the inkjet printer 100.

[0010] As shown in FIG. 1, the inkjet printer 100 is a serial-type image forming device, and includes a device main body 101, a paper feeder 102 disposed below the device main body 101, and a winding device 103 disposed opposite the paper feeder 102.

[0011] The paper feeder 102 may be separate from the device main body 101 and disposed below the device main body 101, or may be configured as an integral part of the device main body 101 as shown in Fig. 2. Similarly to the paper feeder 102, the winding device 103 may be separate from the device main body 101 and disposed below the device main body 101, or may be configured as an integral part of the device main body 101 as shown in Fig. 2.

[0012] The device main body 101 shown in Figure 2 has inside it a paper feeding device 102 that feeds roll paper 112, which is a roll of continuous sheet-like medium, a winding device 103 that winds up the roll paper 112, and an image forming unit 104 that forms an image on the roll paper 112.

[0013] The image forming unit 104 is configured such that a carriage 5 supported by a guide rod 1 and a guide stay 2, which are guide members suspended between both side plates, can move in the direction of arrow A in FIG. 3 (main scanning direction, carriage movement direction).

[0014] 3, the image forming unit 104 has a main scanning motor 8, which is a drive source for reciprocating the carriage 5, disposed on one side in the main scanning direction. A timing belt 11 is wound around a drive pulley 9, which is rotationally driven by the main scanning motor 8, and a driven pulley 10, which is disposed on the other side in the main scanning direction. A belt holding portion of the carriage 5 is fixed to the timing belt 11, and the carriage 5 is reciprocated in the main scanning direction by driving the main scanning motor 8.

[0015] A plurality of recording heads 6a to 6d, each of which integrates a liquid ejection head for ejecting liquid onto a medium to form an image and a head tank for supplying liquid to the liquid ejection head, are mounted on the carriage 5. In the following description, when there is no need to distinguish between the individual recording heads 6a to 6d, they will simply be referred to as "recording head 6."

[0016] Here, recording head 6a and recording heads 6b to 6d are arranged with a positional shift of one head (one nozzle row) in the sub-scanning direction (direction of arrow B), which is perpendicular to the main scanning direction. Furthermore, recording head 6 has nozzle rows made up of multiple nozzles that eject droplets arranged in the sub-scanning direction perpendicular to the main scanning direction, and is mounted with the droplet ejection direction facing downward.

[0017] Each of the recording heads 6a to 6d has two nozzle rows. The recording heads 6a and 6b eject black droplets from both nozzle rows. The recording head 6c ejects cyan (C) droplets from one nozzle row, and the other nozzle row is an unused nozzle row. The recording head 6d ejects yellow (Y) droplets from one nozzle row, and magenta (M) droplets from the other nozzle row.

[0018] As a result, monochrome images can be formed using recording heads 6a and 6b in one scan (one main scan) with a width equivalent to two heads, while color images can be formed using recording heads 6b to 6d, for example. Note that the head configuration is not limited to this, and multiple recording heads may also be arranged side by side in the main scan direction.

[0019] An encoder sheet 12 is arranged along the movement direction of the carriage 5, and the carriage 5 is provided with an encoder sensor 13 that reads the encoder sheet 12. The encoder sheet 12 and encoder sensor 13 form a linear encoder 14, and the position and speed of the carriage 5 are detected from the output of the linear encoder 14.

[0020] In the recording area of ​​the main scanning area of ​​the carriage 5, roll paper 112 is fed from a paper feeder 102 and transported intermittently by transport means 21 in a direction perpendicular to the main scanning direction of the carriage 5 (sub-scanning direction, paper transport direction: direction of arrow B). As shown in FIG. 1, ink of each color is supplied to the head tank of the recording head 6 via a supply tube from an ink cartridge 60, which is a main tank that is replaceably mounted in the device main body 101. In addition, on one side of the main scanning direction of the carriage 5, a maintenance and recovery mechanism 80 that performs maintenance and recovery of the recording head 6 is arranged beside the transport guide member 25 (see FIG. 1).

[0021] 2, the conveying means 21 has a conveying roller 23 that conveys roll paper 112, which is a roll-shaped medium fed from the paper feeder 102, and a pressure roller 24 that is disposed opposite the conveying roller 23. Downstream of the conveying roller 23, the conveying means 21 has a conveying guide member 25 formed with a plurality of suction holes, and a suction fan 26 as suction means that draws air through the suction holes of the conveying guide member 25.

[0022] A cutter is disposed downstream of the conveying means 21 as cutting means for cutting the roll paper 112 on which an image has been formed by the recording head 6 to a predetermined length.

[0023] The roll paper 112 loaded in the paper feeder 102 is a long rolled medium, sheet 120 (this corresponds to the above-mentioned "roll media as continuous sheet-like medium"), wound in a roll shape around a hollow shaft 114, such as a paper tube, which serves as a core member. In this embodiment, the roll paper 112 can be either one in which the end of the roll paper 112 is fixed to the hollow shaft 114 by gluing or other adhesive, or one in which the end of the roll paper 112 is not fixed to the hollow shaft 114 and is not glued.

[0024] As already shown in Figure 2, on the device main body 101 side, there are arranged a guide member 130 that guides the roll paper 112 pulled out from the roll paper 112 of the paper feed device 102, and a paper discharge guide member 131 that guides the roll paper 112 after suction downstream of the transport guide member 25.

[0025] The winding device 103 has a hollow shaft 115 such as a paper tube that serves as a core member. The leading end of the roll paper 112 is adhered to the hollow shaft 115 with tape or the like.

[0026] In the inkjet printer 100 configured as described above, when an image formation process is performed, the carriage 5 moves in the main scanning direction, and the roll paper 112 fed from the paper feeder 102 is intermittently fed by the transport means 21. The recording head 6 is then driven in accordance with image information (print information) to eject droplets, thereby forming a desired image on the roll paper 112. The roll paper 112 with this image formed is guided by the paper discharge guide member 131 and taken up around the hollow shaft 115 in the winder 103. The roll paper 112 on the transport roller 23 is transported while tension is applied from both the paper feeder 102 side and the winder 103 side. Each of these tensions affects transport accuracy.

[0027] Next, a roll body holding device 200 will be described as an embodiment of a roll media holding device according to the present invention. Fig. 4 is a side view illustrating an example of the overall image of the roll body holding device 200, and Fig. 5 is a rear view of the roll body holding device 200. As shown in Fig. 1, the roll body holding devices 200 are configured to hold both side edge portions of the roll paper 112, and are therefore used as a pair. The following description will show only one of the pair of roll body holding devices 200. It is assumed that devices with a similar configuration are positioned to hold both side edge portions of the roll paper 112, making it possible to transport the roll paper 112 as described above.

[0028] 4 and 5, the roll body holding device 200 has the appearance of a box-shaped body in the shape of a substantially rectangular prism, and a core holding mechanism 210 is provided on one of its sides, the surface facing the roll paper 112. The roll body holding device 200 also includes a slider 220 and a lock lever 230. The roll body holding device 200 is held via the slider 220 on a guide rail 240 as a guide member so that it can slide in only one direction. As shown in FIG. 1, the guide rail 240 constitutes part of the paper feeder 102 and the winding device 103, and holds the roll body holding device 200 so that it can move in a direction parallel to the direction of arrow A in FIG. 1.

[0029] The core holding mechanism 210 is fitted into the hollow shaft of the paper roll 112 to hold the paper roll 112 in a predetermined position. A more detailed description of the core holding mechanism 210 will be given later.

[0030] The slider 220 is a movement guide member that allows movement of the core holding mechanism 210 in the width direction W of the paper roll 112 and restricts movement of the core holding mechanism 210 in a direction perpendicular to the width direction W. As shown in FIG. 5, the slider 220 is configured so that its movement in the width direction W of the paper roll 112 is restricted by a guide groove 241 provided in a guide rail 240. The slider 220 is mounted on the bottom surface of the housing of the roll body holding device 200.

[0031] The lock lever 230 is a movement restricting member that restricts movement of the roll body holding device 200, which is held on the guide rail 240 by the slider 220, in the width direction W when the roll body holding device 200 is held so as to be movable in the width direction W. When the lock lever 230 is operated, the slider 220 transitions from a state in which it is not pressed against the inner wall of the guide groove 241 to a state in which it is pressed against the inner wall. The frictional force applied by this operation restricts the movement of the roll body holding device 200. Furthermore, by reversing the operation of the lock lever 230, the slider 220 transitions from a state in which it is pressed against the inner wall of the guide groove 241 to a state in which it is not pressed against the inner wall. This operation restores a state in which no frictional force is applied, allowing the roll body holding device 200 to move.

[0032] That is, by operating the lock lever 230, the roll body holding device 200 can transition between a state in which movement of the roll paper 112 in the width direction W is restricted (locked state) and a state in which movement of the roll paper 112 is not restricted (unlocked state). The lock lever 230 is provided on the side opposite the side on which the core holding mechanism 210 is provided. In other words, the lock lever 230 is located on the side opposite the side on which the roll paper 112 is held, and on the side that is easier for the user to operate.

[0033] 5, slider 220 is a protruding member attached to the bottom surface of roll body holding device 200, and is inserted into the opening of guide groove 241 provided in guide rail 240 from the width direction W of the paper roll 112, allowing it to move in the width direction W. However, movement of the paper roll 112 in a direction perpendicular to the width direction W is restricted by collision with the inner wall of guide groove 241.

[0034] 1, and is arranged along the longitudinal direction of hollow shaft 114 fixed to paper feeder 102 and hollow shaft 115 fixed to winding device 103. Guide rail 240 is longer than the width dimension of roll paper 112, and is provided at a position that connects the bottom surfaces of paper feeder 102 and winding device 103.

[0035] When using the roll body holding device 200 to secure the paper roll 112, one of the roll body holding devices 200 provided in the paper feeder 102 is made to hold one side end portion of the hollow shaft 114, which is the hollow portion of the paper roll 112. Then, the other roll body holding device 200 is moved to a holding position on one side end portion of the hollow shaft 114, and the lock lever 230 is operated to secure the position of the paper roll 112 in the width direction W. At this time, the roll body holding device 200 can be moved and secured so as to fix the axial center position of the paper roll 112, so the axial center position of the paper roll 112 can be secured and held in a predetermined position with a simple operation.

[0036] <Details of the core holding mechanism 210> Next, a more detailed description will be given of the structure of the core holding mechanism 210 for fixing and holding the axial center position of the roll paper 112. Figure 6 shows a side view of the core holding mechanism 210.

[0037] As shown in FIG. 6, the core holding mechanism 210 can be roughly divided into three parts in the width direction W of the roll paper 112: a media insertion section 211, a media positioning section 212, and a holding rotation section 213.

[0038] The media insertion section 211 is a cylindrical section with a diameter that can be inserted into and fitted onto the hollow shaft 114 (or hollow shaft 115) that serves as the core of the roll paper 112, and temporarily holds the side edge of the roll paper 112 immediately after insertion. Multiple media holding members 216 are arranged on the outer circumferential surface of the media insertion section 211.

[0039] The media positioning unit 212 has an inclined portion 214 that comes into contact with the side edge of the paper roll 112. The inclined portion 214 is an annular inclined surface that expands in diameter from the media insertion unit 211 toward the holding and rotating unit 213. By fixing the roll body holding device 200 to the guide rail 240 with the side edge of the paper roll 112 in contact with this inclined portion 214, the roll axis position of the paper roll 112 is determined at a predetermined position. Because the inclined portion 214 is configured as a slope, even if there is variation in the inner diameter of the core material of the paper roll 112, it is possible to prevent the axis from shifting from a predetermined, optimal position when the paper roll core holding mechanism 210 holds the paper roll 112.

[0040] The holding and rotating part 213 is provided on one side of the roll body holding device 200 and is rotatably held by a core holding mechanism central shaft 215 that extends in the width direction W of the roll paper 112.

[0041] In other words, the core holding mechanism 210 can rotatably hold the roll paper 112, the position of which is precisely positioned by the inclined portion 214 and the media insertion portion 211, by using the holding rotation portion 213 with the core holding mechanism central axis 215 as the rotation axis.

[0042] [Details of media insertion section 211] Figure 7 is a front cross-sectional view of the core holding mechanism 210. As shown in Figure 7, media holding members 216 are arranged at equal intervals (120-degree intervals) around a circumference of a circle centered on the core holding mechanism central axis 215. Each of the multiple media holding members 216 has an inner circumferential contact member 2161 that is biased radially outward from the media insertion section 211 by the biasing force of an individual elastic member. Each media holding member 216 is held by an individual rotation shaft inside the media insertion section 211. This rotation shaft rotatably holds the inner circumferential contact member 2161. The inner circumferential contact member 2161 is held by this rotation shaft so that it can rotate within a predetermined angular range.

[0043] [First embodiment of the medium holding member 216] Next, a first embodiment of the media holding member 216 will be described using Figures 8 and 9. Figure 8 is a schematic side view of the media holding member 216 according to this embodiment. Figure 9 is a schematic front view of the media holding member 216 according to this embodiment. As shown in Figure 8, the media holding member 216 has a holding member support shaft 2163 that is fixed and supported by a pair of support plates 2165, 2166 that are arranged to stand upright in the radial direction from the core holding mechanism central shaft 215. An inner peripheral contact member 2161 that contacts the inner peripheral surface of the hollow portion of the roll paper 112 is rotatably held by the holding member support shaft 2163.

[0044] An inner circumferential contact member 2161 serving as a contact member is paired with an elastic member fixing plate 2164 disposed on the opposite side of the holding member support shaft 2163. As shown in Fig. 9, a spring member 2162 serving as an elastic member is disposed between the inner circumferential contact member 2161 and the elastic member fixing plate 2164. The spring member 2162 is, for example, a compression spring.

[0045] An elastic member fixing plate 2164 serving as a fixing member is fixed to the holding member support shaft 2163. One end of a spring member 2162 is fixed to the elastic member fixing plate 2164, and the other end is positioned so as to contact the inner peripheral contact member 2161. Multiple spring members 2162 are positioned symmetrically around the holding member support shaft 2163. The spring members 2162 urge the inner peripheral contact member 2161 outward in the radial direction of the roll paper 112.

[0046] That is, the inner peripheral contact member 2161 is rotatable around an axis parallel to the axial direction of the roll paper 112 as the center of rotation, supported by the holding member support shaft 2163 and biased by the spring member 2162, and is capable of moving in the radial direction of the roll paper 112.

[0047] With the media holding member 216 according to the embodiment described above, when roll paper 112 is inserted into the media insertion section 211 as shown in FIG. 7 , the spring member 2162 urges the edge of the inner contact member 2161 toward the inner circumferential surface of the hollow core of the roll paper 112. When this edge pressure causes the roll paper 112 to rotate relative to the roll body holding device 200, the frictional force (holding force) of the edge of the inner contact member 2161 causes the media holding member 216 to rotate around an axis (holding member support shaft 2163) parallel to the axial direction of the core holding mechanism central axis 215. The media holding member 216 then expands in the radial direction of the roll paper 112. This locks the relative rotation of the roll paper 112 held by the roll body holding device 200.

[0048] [Second embodiment of the medium holding member 216] Next, a second embodiment of the medium holding member 216 will be described using Figure 10. Figure 110 is a schematic side view of the medium holding member 216 according to this embodiment. Figure 11 is a schematic front view of the medium holding member 216 according to this embodiment. As shown in Figures 10 and 11, in addition to the configuration of the medium holding member 216 according to the first embodiment, the medium holding member 216 has a cam 2167 as a cam member to which the core holding mechanism central shaft 215 is attached, and a cam operating member 2168 that operates the cam 2167.

[0049] 10, the inner peripheral contact member 2161 provided on the medium holding member 216 according to this embodiment does not fasten the elastic member fixing plate 2164 to the holding member support shaft 2163, but is supported so as to be movable in the radial direction of the roll paper 112, using the holding member support shaft 2163 as a guide. The position of the elastic member fixing plate 2164 (the position in the radial direction of the roll paper 112) is determined by a cam 2167.

[0050] Therefore, by operating the cam operating member 2168 to move the cam 2167, it is possible to vary the distance of the cam surface of the cam 2167 from the central axis 215 of the winding core holding mechanism. Because the cam surface of the cam 2167 abuts against one surface of the elastic member fixing plate 2164, the position of the elastic member fixing plate 2164 also changes in accordance with the change in the position of the cam surface. As the position of the elastic member fixing plate 2164 changes, the fixing position of the spring member 2162 also changes. As the fixing position of the spring member 2162 changes, the urging force that the spring member 2162 applies to the inner peripheral contact member 2161 also changes.

[0051] That is, in the roll body holding device 200 equipped with the media holding member 216 according to this embodiment, by operating the cam 2167, when inserting the roll paper 112, the inner circumferential contact member 2161 can be moved to a position where it does not come into contact with the hollow inner surface of the roll paper 112. Then, after inserting the roll paper 112, if the inner circumferential contact member 2161 is moved to a position where it abuts against the hollow inner surface of the roll paper 112, the operating force required to insert the roll can be reduced.

[0052] The roll holding device 200 described above has a tapered section for positioning the media in addition to the media insertion section 211, which serves as a media rotation lock mechanism that prevents movement in the rotational direction of the roll paper 112. The media rotation lock mechanism has a media holding member 216 that is rotatable about an axis parallel to the axial direction of the roll media, movable in the radial direction of the media, and biased by an elastic member in the direction of the media's inner circumference. This configuration improves the positioning accuracy of the roll paper 112 and improves the holding force in the rotational direction of the media.

[0053] The present invention is not limited to the above-described embodiments, and various modifications are possible without departing from the technical gist thereof. The present invention covers all technical matters included in the technical ideas described in the claims. The above-described embodiments are preferred examples, but a person skilled in the art can realize various modifications from the disclosed contents. Such modifications are also included in the technical scope described in the claims. [Explanation of symbols]

[0054] 100: Inkjet printer 101: Device body 102: Paper feeder 103: Winding device 104: Image forming unit 112: Roll paper 114:Hollow shaft 115:Hollow shaft 120: Sheet 130: Guide member 131: Paper ejection guide member 200: Roll body holding device 210: Core holding mechanism 211: Media insertion section 212: Media positioning unit 213: Rotating holding part 214: Inclined part 215: Core holding mechanism center shaft 216: Media holding member 220: Slider 230: Lock lever 240: Guide rail 241: Guide groove 2161: Inner contact member 2162: Spring member 2163: Support shaft for holding member 2164: Elastic member fixing plate 2165: Support plate 2166 :Support plate 2167: Cam 2168: Cam operating member [Prior art documents] [Patent documents]

[0055] [Patent Document 1] Patent Publication No. 2003-266845

Claims

1. A roll media holding device that rotatably holds a roll media, a media positioning section having an inclined surface with which a side end of the roll media comes into contact; a media holding section that is rotatably held around an axis parallel to the rotation axis of the roll media, and that is movable in the radial direction of the roll media and is biased from the rotation axis of the roll media toward the inner peripheral surface of the roll media; having The media holding unit includes a contact member that contacts the roll media, a fixed member that is disposed symmetrically about a support shaft that supports the contact member, and an elastic member that is fixed at one end to the contact member and at the other end to the fixed member. having The elastic member is configured as a pair sandwiching the support shaft, Each of the elastic members biases an end of the contact member radially outwardly of the inner circumferential surface of the roll medium. A roll media holding device.

2. The media holding section includes a cam member that changes the position of the fixed member, and a cam operating member that changes the position of the fixed member by displacing a cam surface of the cam member. having The roll media holding device according to claim 1 .

3. The roll media holding device according to claim 1 or 2, wherein the media holding sections are arranged at equal intervals in a rotational direction of the roll media.

4. an image forming unit that forms an image on a roll medium; The roll media holding device according to claim 1 , which holds the roll media so as to be transportable to the image forming unit; An image forming apparatus comprising:

Images