Printer

Abstract

This printer has a main body, a transport unit, a printing unit, a guide member, and a protrusion. The main body comprises an accommodating unit that rotatably accommodates a roll obtained by winding a long print medium in a roll shape. The transport unit draws out the print medium from the roll accommodated in the accommodating unit and feeds the print medium out of the main body. The printing unit prints information on the print medium drawn out from the roll by the transport unit. The guide member is attached to the accommodating unit, has a guide surface facing an end part of the roll in the axial direction, and restricts movement of the roll in the axial direction by bringing the end part of the roll into contact with the guide surface. The protrusion extends from the guide surface to restrict movement of the roll in the draw-out direction of the print medium, and is disposed on a movement path of the roll in the draw-out direction.

Description

Printer

[0001] An embodiment of the present invention relates to a printer that prints information on a long printable medium wound in a roll, for example.

[0002] For example, labels to be pasted on food packages in supermarkets and the like have an adhesive applied to the surface opposite to the printing surface, and are circulated in a state of being wound in a roll after being arranged and pasted on a long release paper. There is also an environmentally friendly label roll in which the printing surface of a long linerless label without release paper is subjected to a peeling treatment and wound in a roll.

[0003] Some printers for printing information on linerless labels without release paper adopt a so-called drop-in method in which a label roll can be loaded simply by opening a cover and putting it into a hopper of the main body in order to facilitate the replacement work of the label roll.

[0004] Japanese Patent Application Laid-Open No. 2022-135695

[0005] Since a drop-in type printer has no shaft for rotatably supporting a label roll, when pulling out a linerless label from the roll, the label roll is likely to be exposed in the hopper.

[0006] When the roll diameter of the label roll is large, even if the linerless label is pulled out, the label roll is located at the bottom of the hopper due to its own weight. However, as the roll diameter of the label roll decreases and becomes lighter during use, the label roll is pulled up in the pulling direction of the linerless label.

[0007] For example, when using a label roll wound with a linerless label coated with a weakly adhesive adhesive that allows re-peeling, the label roll pulled up as the roll diameter decreases collides with a component on the cover side, and after stopping the pulling of the linerless label, it falls to the bottom of the hopper while rotating.

[0008] When the label roll moves up and down within the hopper in this manner, it can collide with the bottom of the hopper or components on the cover side, generating unwanted vibrations. These vibrations are transmitted to the print head, causing misalignment of the linerless label's transport position and resulting in blurry printing, thus degrading print quality.

[0009] The problem that this invention aims to solve is to provide a printer capable of high-quality printing.

[0010] Figure 1 is an external perspective view showing a printer according to an embodiment. Figure 2 is a cross-sectional view showing the printer of Figure 1. Figure 3 is a partially enlarged view showing a part of the main body of the printer of Figure 1. Figure 4 is a schematic diagram showing the mounting structure of the cover of the printer of Figure 1 to the main body. Figure 5 is a perspective view for explaining the mounting structure of the paper guide to the hopper of the printer of Figure 1. Figure 6 is a perspective view of the structure of Figure 5 from a different direction. Figure 7 is a plan view showing the state in which the two paper guides are mounted on the outside of the hopper. Figure 8 is a plan view showing the state in which the two paper guides are mounted on the inside of the hopper. Figure 9 is a cross-sectional view showing the state in which the label roll fed into the printer of Figure 1 has become smaller in diameter. Figure 10 is a cross-sectional view showing the state in which the label roll of Figure 9 has become even smaller in diameter. Embodiment

[0011] The printer of this embodiment comprises a main body, a transport unit, a printing unit, a guide member, and a projection. The main body includes a storage unit that rotatably houses a roll in which a long medium to be printed is wound into a roll shape. The transport unit pulls the medium to be printed from the roll housed in the storage unit and sends it out of the main body. The printing unit prints information on the medium to be printed that has been pulled from the roll by the transport unit. The guide member is attached to the storage unit and has a guide surface facing the axial end of the roll, and restricts the axial movement of the roll by bringing the end of the roll into contact with the guide surface. The projection protrudes from the guide surface and is positioned on the path of movement of the roll in the direction of pulling out the medium to be printed, so as to restrict the movement of the roll in the direction of pulling out the medium to be printed.

[0012] The printer 100 according to this embodiment will be described below with reference to the drawings. As shown in Figures 1 and 2, the printer 100 comprises a main body 10 equipped with a hopper 2 capable of accommodating a label roll R, and a cover 20 for opening and closing the hopper 2. The cover 20 is a separate structure from the main body 10 and is equipped with a pivot shaft 21 for rotatably attaching it to the main body 10. The hopper 2 is an example of a storage section that rotatably accommodates a label roll R. Figure 2 shows the state in which an unused label roll R of the largest diameter is inserted into the hopper 2, a linerless label L is pulled out, and the cover 20 is closed.

[0013] The printer 100 has a transport path T connected to the hopper 2 between the main body 10 and the cover 20. The printer 100 pulls out linerless labels L from the label roll R fed into the hopper 2, transports them through the transport path T, prints predetermined information, and then discharges them from the discharge port 1. The discharge port 1 is located at the downstream end of the transport path T, separated from the hopper 2. When the cover 20 is rotated from the closed position shown in the figure to the open position not shown, the hopper 2 is opened and the upper side of the transport path T is opened, allowing the label roll R to be fed into the hopper 2.

[0014] The printer 100 of this embodiment employs a so-called drop-in method in which the label roll R is loaded into the main body 10 simply by inserting the label roll R into the hopper 2. For this reason, there is no shaft in the hopper 2 that rotatably supports the label roll R, and the label roll R is movable within the hopper 2. At the bottom of the hopper 2 are a plurality of guide rolls 19, 191 that are rotatably mounted on the outer surface of the label roll R, and the label roll R rotates within the hopper 2 with its outer surface in contact with the plurality of guide rolls 19, 191. The plurality of guide rolls 19, 191 have rotation axes that are substantially parallel to the rotation axis of the label roll R inserted into the hopper 2.

[0015] In the following explanation, the open side of the hopper 2 of the printer 100 shown in Figure 1, i.e., the side with the cover 20 positioned in the closed position shown, is defined as the top, the right side is defined as the front, and the left side is defined as the rear. The front, back, up, down, and left and right directions are defined when viewing the printer 100 from the front. In each figure, the direction from left to right of the printer 100 is indicated by arrow X, the direction from back to front is indicated by arrow Y, and the direction from bottom to top is indicated by arrow Z.

[0016] The label roll R is an example of a roll fed into the printer 100, and is a roll made by winding a long, strip-shaped linerless label L without a release liner. The linerless label L is an example of a printing medium and has a printing surface that is located on the outside of the label roll R. An adhesive is provided on the side of the linerless label L opposite to the printing surface. The printing surface is treated to release the adhesive. The adhesive has, for example, a weak adhesiveness that allows the label to be peeled off again. The label roll R is not limited to one wound with a linerless label L as in this embodiment, but may also be a roll made by winding multiple labels laid side by side on a long release liner.

[0017] The label roll R is fed into the hopper 2 in the orientation shown in Figure 2. When a linerless label L is pulled out from the label roll R fed into the hopper 2 in this orientation, the label roll R rotates counterclockwise in Figure 2. In other words, the label roll R is fed into the hopper 2 in a direction that pulls out the linerless label L from the bottom side of the label roll R, which is facing the bottom of the hopper 2. When the label roll R is fed into the hopper 2 in this orientation, the printed surface of the linerless label L pulled out from the label roll R faces the print head 12, which will be described later.

[0018] As shown in Figure 3, the printer 100 has a print head 12 on the main body 10 side of the transport path T near the output port 1. The print head 12 functions as a printing unit that prints information on the print surface of the linerless label L. The print head 12 has a length that exceeds the width of the linerless label L. The print head 12 is, for example, a thermal head.

[0019] The printer 100 includes a swing arm 13 that holds the print head 12 so as to be able to swing toward and toward the transport path T. The support frame 15 of the main body 10 includes a pivot shaft 14 that rotatably supports the base end of the swing arm 13. The base end of the swing arm 13 has a hook 131 for rotatably attaching the swing arm 13 to the pivot shaft 14. The pivot shaft 14 extends in the left-right direction, and the swing arm 13 is able to swing about the pivot shaft 14 in the direction that moves the print head 12 toward and toward the transport path T, i.e., in the clockwise and counterclockwise directions shown.

[0020] Between the support frame 15 and the oscillating arm 13 is a pressure spring 16 for pressing the print head 12 against the platen roller 22, which will be described later. The pressure spring 16 is positioned in the front-rear direction. The support frame 15 fixes the base end of the pressure spring 16. The tip of the pressure spring 16 is fixed to the oscillating arm 13. The support frame 15 is equipped with a stopper (not shown). With the cover 20 open, the stopper engages with the oscillating arm 13, which is pushed by the pressure spring 16 and rotates in the counterclockwise direction shown, to stop the oscillating arm 13 at a predetermined rotation position.

[0021] With the rotation of the swing arm 13 stopped by the stopper, the compression spring 16 is slightly compressed, causing the print head 12 to protrude slightly beyond the transport path T towards the cover 20. In other words, with the cover 20 open, the stopper locks the swing arm 13 in a position where the print head 12 protrudes slightly beyond the transport path T towards the cover 20. As a result, when the cover 20 is closed, the print head 12 is slightly pushed towards the main body 10 by contact with the platen roller 22 (described later), creating a pressing force between the print head 12 and the platen roller 22.

[0022] The printer 100 is equipped with a platen roller 22 on the cover 20 side facing the print head 12 with the transport path T in between, which rotates while holding the linerless label L between itself and the print head 12. The rotation axis 221 of the platen roller 22 attached to the cover 20 extends in the left-right direction. The platen roller 22 contacts the surface of the linerless label L being transported along the transport path T that is opposite to the printing surface and rotates in the counterclockwise direction shown in the figure. With the cover 20 closed in the closed position, the platen roller 22 is in a position to press the linerless label L passing through the transport path T between itself and the print head 12. The platen roller 22 functions as a transport unit that pulls the linerless label L from the label roll R fed into the hopper 2 and sends it out from the discharge port 1.

[0023] The printer 100 is equipped with a cutter 23 downstream of the platen roller 22, along the direction in which the linerless label L is pulled out. The printer 100 is equipped with a cutter motor 24 for operating the cutter 23. The cutter 23 and cutter motor 24 are components on the cover 20 side, which are attached to the cover 20. The cutter 23 divides the printed linerless label L into multiple labels.

[0024] The cover 20 has a pivot shaft 21 that rotatably connects the cover 20 to the main body 10. The pivot shaft 21 extends in the left-right direction near the rear end of the cover 20. As shown in Figure 4, the main body 10 has a substantially oval-shaped slot 11 that slidably and rotatably receives the pivot shaft 21 of the cover 20 in the front-rear direction. The slot 11 extends in the direction in which the press spring 16 presses the print head 12 against the platen roller 22, i.e., in the front-rear direction. The slot 11 is located above the hopper 2 and near the rear end of the main body 10. In this embodiment, the pivot shaft 21 is provided in the cover 20 and the slot 11 is provided in the main body 10, but the pivot shaft may be provided in the main body 10 and the slot 11 in the cover 20.

[0025] The cover 20 is rotatable relative to the main body 10 around the pivot axis 21, between a closed position shown in Figure 1, which closes the opening at the top of the hopper 2, and an open position (not shown). Furthermore, when the cover 20 is positioned in the closed position, it is slightly movable relative to the main body 10 in the direction of the elongated hole 11 (front-to-back direction). When the cover 20 is moved forward relative to the main body 10, the platen roller 22 moves slightly in the direction that pushes the print head 12. When the cover 20 is moved backward relative to the main body 10, the platen roller 22 moves slightly in the direction that moves away from the print head 12.

[0026] The printer 100 has a motor (not shown) and a drive transmission mechanism for rotating the platen roller 22. The cutter 23, cutter motor 24, and platen roller 22 described above are attached to the cover 20, and these components on the cover side move together with the cover 20.

[0027] The printer 100 has a locking claw (not shown) for fixing the cover 20, which is positioned in the closed position, to the main body 10. The locking claw prevents the cover 20 from opening unintentionally when it is in the closed position. The locking claw has a structure that does not hinder the movement of the cover 20 in the front-rear direction relative to the main body 10. The locking of the cover 20 by the locking claw can be released by operating a lever 201 provided on the upper side of the cover 20. In other words, by pulling the lever 201 in Figure 1, the locking of the claw is released, and the cover 20 can be opened from the closed position to the open position.

[0028] The printer 100 is equipped with a swing plate 17 on the main body 10 side of the transport path T between the hopper 2 and the print head 12, for applying a predetermined tension to the linerless label L pulled from the label roll R. The swing plate 17 has a hook 171 at its base end for fixing one end of a tension spring 170 stretched between it and the main body 10. The swing plate 17 has a guide roll 172 at its tip that rotates in contact with the printing surface of the linerless label L.

[0029] The oscillating plate 17 is equipped with a pivot shaft 173 near the base end of its oscillation between the hook 171 and the guide roll 172, for rotatably connecting to the main body 10. The pivot shaft 173 extends in the left-right direction and is located slightly away from the hook 171 toward the tip. A bearing 174 for rotatably mounting the pivot shaft 173 of the oscillating plate 17 is provided on the main body 10 adjacent to the transport path T. A tension spring 170, with one end fixed to the hook 171, is slightly stretched and has its other end fixed to the hook 18 on the main body 10 side.

[0030] The oscillating plate 17 is biased in a counterclockwise direction around the pivot axis 173 by the restoring force of the tension spring 170, causing the guide roll 172 to oscillate in a direction that presses against the printed surface of the linerless label L. By pressing against the printed surface of the linerless label L, the oscillating plate 17 applies a predetermined tension to the linerless label L.

[0031] As shown in Figure 2, when the label roll R with the largest diameter is fed into the hopper 2, the inertia of the label roll R is large, and the linerless label L pulled out from the label roll R by the rotation of the platen roller 22 is subjected to maximum tension. For this reason, when the label roll R with the largest diameter is fed into the hopper 2, the oscillating plate 17 is positioned on the main body 10 side of the transport path T, at the position shown by the solid line in Figure 2 along the transport path T.

[0032] In contrast, as shown in Figure 3, for example, as the diameter of the label roll R decreases over time, the inertia of the label roll R also decreases, and the tension of the linerless label L pulled out from the label roll R by the rotation of the platen roller 22 also decreases. Therefore, as the diameter of the label roll R decreases, the oscillating plate 17 oscillates in the counterclockwise direction shown in Figure 3 from the position shown by the dashed line to the position shown by the solid line, applying a predetermined tension to the linerless label L.

[0033] The printer 100 is equipped with a flapper 4 that presses the label roll R, which has been fed into the hopper 2, against the bottom of the hopper 2. The flapper 4 suppresses the "flapping" of the label roll R by pressing it downwards from above the hopper 2. When the diameter of the label roll R decreases and it becomes lighter due to the dispensing of the linerless labels L, the label roll R becomes more likely to move in the direction of dispensing the linerless labels L within the hopper 2, causing the label roll R to move more freely within the hopper 2, resulting in what is known as "flapping".

[0034] The cover 20 has a pivot shaft 25 for rotatably attaching the base end of the flapper 4. The pivot shaft 25 extends in the left-right direction. There is a link mechanism (not shown) between the flapper 4 and the main body 10. The link mechanism links the flapper 4 to the opening and closing operation of the cover 20. The link mechanism limits the swing range of the flapper 4. Since the link mechanism is a well-known technology, a detailed explanation and illustration of it are omitted here.

[0035] The printer 100 is equipped with a torsion coil spring 26 around the pivot axis 25 of the flapper 4. The torsion coil spring 26 biases the flapper 4 in a counterclockwise direction around the pivot axis 25 in Figure 3. In other words, the flapper 4 is biased by the restoring force of the torsion coil spring 26 to press the label roll R against the bottom of the hopper 2. In addition, the flapper 4 moves in a direction toward the inner surface of the cover 20 in conjunction with the movement of the cover 20 to the open position via a link mechanism, so that it becomes approximately parallel to the cover 20 when it is positioned in the open position.

[0036] As in this embodiment, when the flapper 4 is biased in the counterclockwise direction by the torsion coil spring 26, the pressing force applied by the flapper 4 to the label roll R changes according to the diameter of the label roll R fed into the hopper 2. For example, when the label roll R with the largest diameter shown in Figure 2 is fed into the hopper 2, the deformation of the torsion coil spring 26 is at its maximum, and the rotational force applied to the flapper 4 by the torsion coil spring 26 is at its maximum. In contrast, for example, when a label roll R with a smaller diameter is fed into the hopper 2 as shown in Figure 3, the deformation of the torsion coil spring 26 is smaller compared to the state in Figure 2, and the rotational force applied to the flapper 4 by the torsion coil spring 26 is also smaller.

[0037] Thus, with the largest diameter label roll R inserted, the force exerted by the flapper 4 on pressing the label roll R against the bottom of the hopper 2 is maximized, and the conveying force by the platen roller 22 required to pull the linerless label L from the largest diameter label roll R is also maximized. Conversely, the conveying force applied to the linerless label L by the platen roller 22 must be at least large enough to pull the linerless label L from the largest diameter label roll R, and there is an upper limit to the rotational force that can be applied to the flapper 4 by the torsion coil spring 26.

[0038] On the other hand, as the roll diameter of the label roll R decreases, the pressing force by the flapper 4 also decreases, making it difficult to suppress the "flapping" of the label roll R within the hopper 2. However, if the spring constant of the torsion coil spring 26 is made sufficiently large to suppress the "flapping" of the smallest diameter label roll R, it becomes difficult to pull out the linerless label L from the largest diameter label roll R for the reasons mentioned above.

[0039] Therefore, it is desirable to use a torsion coil spring 26 that biases the flapper 4 toward the label roll R, having a spring constant that can easily pull out the linerless label L from the label roll R with the largest diameter, and suppress the "wobbling" of the label roll R with the smallest diameter as much as possible. However, even if a torsion coil spring 26 with a spring constant that generates the maximum pressing force that can pull out the linerless label L from the label roll R with the largest diameter is used, it is difficult for the flapper 4 to completely suppress the "wobbling" of the label roll R with the smallest diameter inside the hopper 2.

[0040] When loading the label roll R into the printer 100, the cover 20 is rotated to an open position (not shown) to create a large opening above the hopper 2. At this time, the flapper 4 moves together with the cover 20 and is not positioned in the loading path of the label roll R. The two paper guides 31 and 32, described later, are pre-installed in predetermined positions according to the size of the label roll R. In this state, the label roll R is loaded from above the hopper 2 in the direction described above. The label roll R is supported so as to be able to roll by contacting the multiple guide rolls 19 and 191 located at the bottom of the hopper 2. Then, the linerless label L is pulled out from the label roll R and positioned along the transport path T, and the leading edge of the linerless label L is led out of the main body 10. After this, the cover 20 is rotated to a closed position that closes the hopper 2.

[0041] As a result, as shown in Figure 2, the leading edge of the linerless label L is led out from the discharge port 1, making it possible to print on the linerless label L. In this state, the label roll R is pressed against multiple guide rolls 19, 191 at the bottom of the hopper 2 by the flapper 4, suppressing the problem of the label roll R moving around inside the hopper 2.

[0042] Incidentally, when the label roll R is inserted and the cover 20 is rotated from the open position toward the closed position, the platen roller 22 is pressed against the print head 12 via the linerless label L, and the platen roller 22 presses the print head 12 forward against the biasing force of the compression spring 16. As a result, the swing arm 13 swings slightly in the clockwise direction in the drawing, and the print head 12 is slightly pushed into the main body 10 side by the platen roller 22.

[0043] After the cover 20 is rotated to the closed position, the swing arm 13 swings slightly in the counterclockwise direction in the drawing by the restoring force of the compression spring 16, and the print head 12 pushes the platen roller 22 backward. As a result, the rotation shaft 21 of the cover 20 abuts against the rear end of the long hole 11 of the main body 10 as shown in FIG. 4, and the cover 20 stops. In this state, a hook (not shown) fixes the cover 20 to prevent the cover 20 in the closed position from rotating toward the open position.

[0044] As shown in FIGS. 5 to 8, the printer 100 has two plate-like paper guides 31 and 32 arranged to face both axial ends of the label roll R inserted into the hopper 2. The paper guides 31 and 32 have a bilaterally symmetric shape and are attached to the bottom wall 202 in a posture parallel to the YZ plane at positions that are axially asymmetric within the hopper 2. The bottom wall 202 defines the bottom of the hopper 2. The paper guides 31 and 32 contact the axial ends of the label roll R inserted into the hopper 2 to restrict the axial movement of the label roll R.

[0045] The printer 100 of the present embodiment can use label rolls R of several types of sizes having different axial lengths, and thus the attachment positions of the two paper guides 31 and 32 can be adjusted according to the size of the label roll R. For example, when using the label roll R having the largest axial size, the distance between the paper guides 31 and 32 is widened as shown in FIG. 7, and when using the label roll R having the smallest size, the distance between the paper guides 31 and 32 can be narrowed as shown in FIG. 8.

[0046] The paper guides 31 and 32 have smooth guide surfaces 310 and 320 facing each other in parallel. The paper guides 31 and 32 function as guide members that regulate the movement of the label roll R outward in the axial direction (left - right direction) by bringing their respective guide surfaces 310 and 320 close to and facing both ends of the label roll R in the axial direction (left - right direction) that is inserted into the hopper 2. The paper guides 31 and 32 have a size and shape such that they are in a non - contact state with the components on the cover 20 side arranged in the closed position.

[0047] As shown in FIG. 5, the main body 10 includes a shaft 33 for rotatably and slidably mounting the rear ends of the two paper guides 31 and 32 near the rear end of the hopper 2. The shaft 33 extends in the left - right direction. The two paper guides 31 and 32 are provided with hooks 34 at their rear ends that engage with the shaft 33 rotatably and slidably. The two paper guides 31 and 32 are slidable in the left - right direction along the shaft 33 and rotatable about the shaft 33 along the YZ plane in a state where the hooks 34 are engaged with the shaft 33.

[0048] The main body 10 has a plurality of slots 341, 342, 351, 352, 361, 362, 371, 372 for positioning and fixing the two paper guides 31 and 32 in the left - right direction on the bottom wall 202 of the hopper 2. The plurality of slots 341, 342, 351, 352, 361, 362, 371, 372 extend parallel to the YZ plane. The plurality of slots 341, 342, 351, 352, 361, 362, 371, 372 are slit - shaped holes penetrating the bottom wall 202 of the hopper 2 or bottomed slit - shaped holes. A part of the peripheries of the two paper guides 31 and 32 attached to the shaft 33 is fitted into each of the plurality of slots 341, 342, 351, 352, 361, 362, 371, 372.

[0049] At the top of the bottom wall 202 on the rear end side of the hopper 2, which is close to the lower part of the shaft 33, there are two outer slots 341 and two inner slots 342 in the left-right direction. Of these four slots 341 and 342, the rightmost slot 341 and the slot 342 inside it are assigned to the right paper guide 31. The leftmost slot 341 and the slot 342 inside it are assigned to the left paper guide 32. The four slots 341 and 342 are substantially the same shape. The projections 311 and 321 located just below the hooks 34 at the rear ends of the two paper guides 31 and 32 can be fitted into the four slots 341 and 342.

[0050] Near the lower end of the bottom wall 202 at the rear end of the hopper 2, spaced apart below the aforementioned slots 341 and 342, are two outer slots 351 and two inner slots 352 in the left-right direction. Of these four slots 351 and 352, the rightmost slot 351 and the slot 352 inside it are assigned to the right-side paper guide 31. The leftmost slot 351 and the slot 352 inside it are assigned to the left-side paper guide 32. The four slots 351 and 352 are substantially the same shape. The claw portions 312 and 322 that protrude rearward from the lower ends spaced apart from the shafts 33 of the two paper guides 31 and 32 can be hooked onto the four slots 351 and 352.

[0051] In front of the aforementioned slots 351 and 352, spaced apart, the bottom wall 202 of the hopper 2 has two outer slots 361 and two inner slots 362 in the left-right direction. Of these four slots 361 and 362, the rightmost slot 361 and the slot 362 inside it are assigned to the right-side paper guide 31. The leftmost slot 361 and the slot 362 inside it are assigned to the left-side paper guide 32. The four slots 361 and 362 are substantially the same shape. Projections 313 and 323, which protrude from the lower ends of the two paper guides 31 and 32, can be fitted into the four slots 361 and 362.

[0052] As shown in Figure 6, the upper part of the front bottom wall 202 of the hopper 2 has two outer slots 371 and two inner slots 372 in the left-right direction. Of these four slots 371 and 372, the rightmost slot 371 and the slot 372 inside it are assigned to the right paper guide 31. The leftmost slot 371 and the slot 372 inside it are assigned to the left paper guide 32. The four slots 371 and 372 are substantially the same shape. Projections 314 and 324 that protrude from the rotating ends of the two paper guides 31 and 32 can be fitted into the four slots 371 and 372.

[0053] Of the 16 slots 341, 342, 351, 352, 361, 362, 371, and 372 mentioned above, the four slots 341, 351, 361, and 371 located on the far right of the hopper 2 position and hold the right-side paper guide 31, which is positioned outward in the left-right direction. The four slots 342, 352, 362, and 372 located inside these four slots 341, 351, 361, and 371 position and hold the right-side paper guide 31, which is positioned inward in the left-right direction. Similarly, the four slots 341, 351, 361, and 371 located on the far left, and the four slots 342, 352, 362, and 372 located inside them, each position and hold the left-side paper guide 32 either outward or inward in the left-right direction.

[0054] For example, when loading the label roll R with the largest axial width into hopper 2, the right-hand paper guide 31 is attached to the four slots 341, 351, 361, and 371 located on the far right side of hopper 2, and the left-hand paper guide 32 is attached to the four slots 341, 351, 361, and 371 located on the far left side of hopper 2. Alternatively, when loading the label roll R with the smallest axial width into hopper 2, the right-hand paper guide 31 is attached to the four slots 342, 352, 362, and 372 located on the far right side of hopper 2, and the left-hand paper guide 32 is attached to the four slots 342, 352, 362, and 372 located on the far left side of hopper 2.

[0055] More specifically, as shown in Figure 6, when loading the label roll R with the longest axial length into the hopper 2, the right-hand paper guide 31 is rotated upward from the hopper 2 around the shaft 33 and slid to a position facing the four rightmost slots 341, 351, 361, and 371. Then, at this position, the paper guide 31 is rotated around the shaft 33 in a direction that approaches the bottom wall 202 of the hopper 2, and a portion of the periphery of the paper guide 31 is fitted into the four slots 341, 351, 361, and 371. At this time, the projection 311 of the paper guide 31 is fitted into slot 341, the claw portion 312 is hooked into slot 351, the projection 313 is fitted into slot 361, and the projection 314 is fitted into slot 371.

[0056] Similarly, the left paper guide 32 is temporarily retracted from the hopper 2 and slid to a position facing the four leftmost slots 341, 351, 361, and 371. Then, at this position, the paper guide 32 is rotated in the opposite direction toward the hopper 2 around the shaft 33, and a portion of the periphery of the paper guide 32 is fitted into the four slots 341, 351, 361, and 371. Specifically, the projection 321 of the paper guide 32 is fitted into slot 341, the claw portion 322 is hooked into slot 351, the projection 323 is fitted into slot 361, and the projection 324 is fitted into slot 371.

[0057] As described above, when the largest size label roll R is inserted between the two paper guides 31 and 32 positioned and mounted on the left and right outer sides of the hopper 2, both axial ends of the label roll R come into close proximity to the guide surfaces 310 and 320 of the left and right paper guides 31 and 32 with a small gap between them. In this state, the two paper guides 31 and 32 restrict the axial movement of the label roll R.

[0058] On the other hand, when loading the label roll R, which has the shortest axial length, into the hopper 2, the two paper guides 31 and 32 are similarly moved out of the hopper 2 and slid to a position facing the inner slots 342, 352, 362, and 372 in the left-right direction, narrowing the distance between them. Then, at this position, the paper guides 31 and 32 are rotated around the shaft 33 toward the bottom wall 202 of the hopper 2, and parts of the periphery of the paper guides 31 and 32 are fitted into the four slots 342, 352, 362, and 372.

[0059] When the smallest size label roll R is inserted between the two paper guides 31 and 32 positioned and mounted on the inside of the hopper 2 in the left-right direction, both axial ends of the label roll R come into close proximity to the guide surfaces 310 and 320 of the left and right paper guides 31 and 32 with a small gap between them. In this state, the two paper guides 31 and 32 restrict the axial movement of the label roll R.

[0060] Furthermore, in addition to the largest label roll R with the longest axial length and the smallest label roll R with the shortest axial length described above, the printer 100 of this embodiment can also use two other types of label rolls R with different axial lengths. For example, by changing the mounting positions of the two paper guides 31 and 32, the printer 100 of this embodiment can handle four types of label rolls R with axial lengths of 40 mm, 58 mm, 62 mm, and 80 mm.

[0061] The two paper guides 31 and 32 each have projections 38 and 39 that project integrally from their guide surfaces 310 and 320 toward the inside of the hopper 2 in the left-right direction. The projections 38 and 39 of the paper guides 31 and 32 are located opposite each other in the left-right direction when the paper guides 31 and 32 are attached to the bottom wall 202 of the hopper 2 as described above. The two projections 38 and 39 have substantially the same structure. The following description of the two projections 38 and 39 will assume that the two paper guides 31 and 32 are attached to the outside of the hopper 2 in the left-right direction to match the largest label roll R.

[0062] The protrusions 38 and 39 are located outside the feeding path for the label roll R with the largest diameter into the hopper 2. By positioning the protrusions 38 and 39 outside the feeding path for the label roll R with the largest diameter, the protrusions 38 and 39 do not interfere with the label roll R when it is fed into the hopper 2. This prevents the label roll R from being damaged by contact with the protrusions 38 and 39 when it is fed into the hopper 2.

[0063] Furthermore, the protrusions 38 and 39 are located downstream of the direction in which the linerless label L is drawn from the label roll R that has been fed into the hopper 2, and are on the movement path of the label roll R as it moves in the direction in which the linerless label L is drawn. Because the guide surfaces 310 and 320 of the two paper guides 31 and 32 are close to the axial ends of the label roll R, the protrusions 38 and 39, which protrude from the guide surfaces 310 and 320 in directions opposite to each other, are positioned on the movement path of the label roll R and interfere with the label roll R as it moves in the direction in which it is drawn. In other words, the protrusions 38 and 39 contact the outer circumferential surface of the label roll R as it moves in the direction in which the linerless label L is drawn, and function to restrict the further movement of the label roll R.

[0064] The projections 38 and 39 have cylindrical surfaces 381 and 391 that bulge backward on the surface that contacts the label roll R, i.e., the rear side surface. As shown in Figures 9 and 10, the cylindrical surfaces 381 and 391 of the projections 38 and 39 can make line contact with the outer surface of the label roll R when the diameter of the label roll R is reduced. The surface on which the projections 38 and 39 contact the label roll R is not limited to a cylindrical surface as in this embodiment; it is desirable that it be a curved surface that does not damage the linerless label L.

[0065] Furthermore, the protrusions 38 and 39 are positioned appropriately to prevent the label roll R, which has become smaller in diameter as shown in Figures 9 and 10, from overcoming the protrusions 38 and 39 and colliding with the protruding portion 27 on the cover 20 when the label roll R moves in the direction of pulling out the linerless label L. The appropriate positions of the protrusions 38 and 39 will be described below.

[0066] As shown in Figure 2, the cover 20 has a guide surface 271 that faces the front outer surface of the label roll R with a small gap between them when the unused label roll R of the largest diameter is loaded into the hopper 2 and positioned in the closed position shown. The guide surface 271 is the surface located on the inside of the cover 20, that is, behind the protruding portion 27 that protrudes downward toward the hopper 2 as shown, when the cover 20 is closed. In this way, when the cover 20 is positioned in the closed position shown in Figure 2, it is in a non-contact state with the label roll R loaded into the hopper 2, and is also in a non-contact state with the two paper guides 31 and 32 attached to the bottom wall 202 of the hopper 2.

[0067] As shown in Figure 3, the tip of the protruding portion 27 of the cover 20 in the protruding direction is the protruding end 272 on the cover 20 side that is closest to the conveying surface S that conveys the linerless label L pulled out from the label roll R. The protruding end 272 of the protruding portion 27 has a guide roll 28 that contacts and guides the linerless label L pulled out from the label roll R, and the lower end in the direction of gravity of the outer circumferential surface of this guide roll 28 is the protruding end 272 of the cover 20.

[0068] The conveying surface S (and the conveying surface in the claims) as used herein is the surface that includes a tangent line extending in the left-right direction where the guide roll 191, which is the downstream guide roll 191 in the direction of pulling out the linerless label L, contacts the outer circumferential surface of the label roll R, among the multiple guide rolls 19 that support the label roll R loaded into the hopper 2 from below in the direction of gravity, and is the surface that contacts the outer circumferential surface of the guide roll 172 when the oscillating plate 17 is positioned at the position shown by the solid line in Figure 2 on the main body 10 side of the conveying path T.

[0069] The component on the cover 20 that the label roll R, which has moved in the pulling direction of the linerless label L after overcoming the protrusions 38 and 39, may collide with is the aforementioned protruding portion 27. Therefore, the protrusions 38 and 39 of the paper guides 31 and 32 are positioned so that the protrusions 38 and 39 contact the label roll R behind an imaginary plane parallel to the XZ plane passing through the protruding end 272 closest to the transport surface S of the protruding portion 27. In this way, by positioning the part of the protrusions 38 and 39 that contacts the label roll R behind the protruding end 272 of the cover 20, contact between the label roll R and the protruding portion 27 is prevented.

[0070] Furthermore, the protrusions 38 and 39 are positioned above an intermediate position between the line where the aforementioned hypothetical surface passing through the protruding end 272 intersects the transport surface S and the protruding end 272, so that the protrusions 38 and 39 contact the label roll R. By positioning the protrusions 38 and 39 in this position, it is possible to prevent the label roll R, regardless of the diameter of the label roll R, from overcoming the protrusions 38 and 39 and colliding with the protruding portion 27 of the cover 20 as it moves in the pulling direction of the linerless label L.

[0071] For example, as shown in Figure 2, when the linerless label L is pulled out with the largest diameter label roll R loaded into the hopper 2, the label roll R rotates in the counterclockwise direction shown in the figure, and the label roll R is pulled in the direction of the linerless label L being pulled out. However, the label roll R is pressed against the bottom of the hopper 2 (guide rolls 19, 191) by the flapper 4, and an inertial force acts to keep it in place due to its own weight, so it does not move in the direction of the linerless label L being pulled out.

[0072] Furthermore, if the diameter of the label roll R is as large as shown in Figure 2, the flapper 4 will contact the label roll R with an inclination such that the tangent line of contact between the flapper 4 and the label roll R approaches the conveying surface S in the direction of the linerless label L being pulled out. As a result, the pressing force applied from the flapper 4 to the label roll R in this state will include a component in the opposite direction to the direction of the linerless label L being pulled out, and a force will act to suppress the movement of the label roll R in the pulling direction.

[0073] Therefore, in the state shown in Figure 2, where an unused label roll R is loaded into the hopper 2, the label roll R will not move in the pulling direction until its diameter becomes somewhat smaller, and the label roll R will not come into contact with the protrusions 38 and 39. Thus, immediately after replacing the label roll R, there will be no problem of the label roll R colliding with the components on the cover 20 side.

[0074] In contrast, as shown in Figure 9, for example, when the diameter of the label roll R is reduced to such an extent that the conveying surface S for transporting the linerless label L and the flapper 4 are approximately parallel, the label roll R moves in the pulling direction as the linerless label L is pulled out, and the outer surface of the label roll R comes into contact with the protrusions 38 and 39. In this state, the label roll R is pressed against the bottom of the hopper 2 by the flapper 4, and the protrusions 38 and 39 are in contact with the label roll R upstream of the protruding end 272 of the cover 20 in the pulling direction, so the label roll R does not collide with the protruding portion 27 of the cover 20.

[0075] Furthermore, as the diameter of the label roll R decreases further due to the pulling out of the linerless label L, the inclination direction of the flapper 4 becomes such that it moves away from the conveying surface S in the direction of pulling out the linerless label L, as shown in Figure 10. In this state, the pressing force applied to the label roll R from the flapper 4 includes a small component in the direction of pulling out the linerless label L. Therefore, if the diameter of the label roll R becomes as small as shown in Figure 10, and the protrusions 38 and 39 are positioned close to the conveying surface S, there is a possibility that the label roll R will go over the protrusions 38 and 39. When the behavior of the label roll R was actually checked by positioning the protrusions 38 and 39 below the midpoint in the vertical direction between the protruding end 272 of the cover 20 and the conveying surface S, the phenomenon of the smallest diameter label roll R going over the protrusions 38 and 39 was observed.

[0076] Therefore, in this embodiment, the projections 38 and 39 are positioned at an appropriate distance above the transport surface S so that even the smallest diameter label roll R does not go over the projections 38 and 39 when moving in the pulling direction of the linerless label L. Specifically, when the projections 38 and 39 are positioned above the midpoint in the vertical direction between the protruding end 272 of the cover 20 and the transport surface S, it was confirmed that the phenomenon of the label roll R going over the projections 38 and 39 does not occur.

[0077] If the protrusions 38 and 39 of the paper guides 31 and 32 are positioned below the aforementioned intermediate position close to the transport surface S of the linerless label L, or if the protrusions 38 and 39 themselves are not provided, a problem will occur in which the label roll R will collide with the protruding portion 27 of the cover 20 when it moves erratically within the hopper 2. When the label roll R collides with the protruding portion 27 of the cover 20 in this way, the cover 20 is pushed forward, and the print head 12 on the main body 10 side is slightly pushed in by the platen roller 22.

[0078] If the print head 12 is pushed forward by the platen roller 22 in this way, it will cause a misalignment in the transport position of the linerless label L, resulting in unclear printing and a decrease in print quality. Therefore, as in this embodiment, it is effective to provide protrusions 38 and 39 on the paper guides 31 and 32 in an appropriate layout to prevent the label roll R from colliding with the components (protruding parts 27) on the cover 20 side.

[0079] Since the printer 100 of this embodiment employs the drop-in method described above, in which the label roll R is simply fed into the hopper 2, unwanted vibrations occur inside the printer 100 due to the "rattling" of the label roll R caused by the pulling out of the linerless label L. In addition to those caused by collisions with the protruding portion 27 of the label roll R as described above, the following are possible causes of such unwanted vibrations.

[0080] For example, when the label roll R collides with the bottom of the hopper 2 due to "vibration," vibrations are transmitted to the main body 10. However, these vibrations are hardly transmitted to the print head 12, which is elastically supported by the main body 10 via the compression spring 16. Therefore, there is no need to worry about the transport position of the linerless label L shifting due to vibrations of the print head 12, nor is there any need to worry about the print becoming unclear.

[0081] Furthermore, if protrusions 38 and 39 are provided on the paper guides 31 and 32 as in this embodiment to prevent the label roll R from colliding with the protruding portion 27 of the cover 20, unwanted vibrations will be transmitted to the paper guides 31 and 32 when the label roll R collides with the protrusions 38 and 39. However, since the paper guides 31 and 32 are attached to the main body 10 (bottom wall 202 of the hopper 2) in a non-contact state with the components of the cover 20, vibrations are hardly transmitted to the print head 12 via the main body 10, so there is no need to worry about the transport position of the linerless label L shifting, and there is no need to worry about the print becoming unclear.

[0082] In other words, in the printer 100 of this embodiment, in order to improve print quality, it is important to eliminate vibrations that are directly transmitted to the cover 20 due to the "vibration" of the label roll R, and it can be said that it is effective to provide protrusions 38 and 39 that obstruct the transmission of vibrations from the paper guides 31 and 32 attached to the hopper 2 of the main body 10.

[0083] In the above-described embodiment, projections 38 and 39 were provided on the two paper guides 31 and 32 attached to the hopper 2 to restrict the movement of the label roll R. However, in a printer that dispenses linerless labels L based on one side in the left-right direction of the hopper 2, it is sufficient to provide one projection from the guide surface of one paper guide.

[0084] As described above, according to this embodiment, even if the label roll R fed into the hopper 2 "wiggles" when the linerless label L is pulled out, the paper guides 31 and 32 are provided with protrusions 38 and 39 so that the label roll R does not collide with the components on the cover 20 side. This suppresses the problem of misalignment in the transport position of the linerless label L, and thus suppresses the problem of unclear printing. Therefore, the printer 100 of this embodiment is capable of high-quality printing.

[0085] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be carried out in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims and their equivalents.

[0086] The embodiments described above may also be expressed as follows: (1) A printer having a main body with a storage section for rotatably housing a roll in which a long medium to be printed is wound into a roll; a transport section for pulling the medium to be printed from the roll housed in the storage section and sending it out of the main body; a printing section for printing information on the medium to be printed pulled out from the roll by the transport section; a guide member attached to the storage section having a guide surface facing the axial end of the roll, and restricting the movement of the roll in the axial direction by bringing the end of the roll into contact with the guide surface; and a projection protruding from the guide surface and positioned on the movement path of the roll in the pulling direction so as to restrict the movement of the roll in the pulling direction of the medium to be printed. (2) The printer according to (1), wherein the projection is located outside the input path for inserting an unused roll having the maximum diameter into the storage section. (3) The printer according to (2), having a cover for opening and closing the housing, wherein the projection is positioned upstream in the pulling direction from the protruding end of the cover closest to the transport surface for transporting the printing medium drawn out from the roll housing the housing, and in contact with the outer circumferential surface of the roll as it moves in the pulling direction. (4) The printer according to (2), having a cover for opening and closing the housing, wherein the projection is positioned above the midpoint in the direction of gravity between the protruding end of the cover closest to the transport surface for transporting the printing medium drawn out from the roll housing the housing and the transport surface, and in contact with the outer circumferential surface of the roll as it moves in the pulling direction. (5) The printer according to (2), having a cover for opening and closing the housing, wherein the projection is positioned upstream in the pulling direction from the protruding end of the cover closest to the transport surface for transporting the printing medium pulled out from the roll housed in the housing, and above the midpoint in the direction of gravity between the protruding end and the transport surface, so as to contact the outer circumferential surface of the roll as it moves in the pulling direction.(6) The printer according to (1), having a cover for opening and closing the housing section, the transport section including a platen roller attached to the cover, the printing section having a print head facing the platen roller with the printing medium in between, with the cover positioned in a closed position that closes the housing section, the print head being attached to the main body via a pressure spring that generates a pressing force toward the platen roller, and the cover being attached to the main body so as to be movable in the direction that generates a pressing force by the pressure spring. (7) The printer according to (6), having a projection located upstream in the pulling direction from the protruding end of the cover closest to the transport surface that transports the printing medium pulled out from the roll housed in the housing section, and in contact with the outer circumferential surface of the roll as it moves in the pulling direction. (8) The printer according to (6), wherein the projection is positioned above the midpoint in the direction of gravity between the protruding end of the cover closest to the transport surface for transporting the printing medium drawn out from the roll housed in the housing and the transport surface, and in contact with the outer circumferential surface of the roll as it moves in the pulling direction. (9) The printer according to (6), wherein the projection is positioned upstream in the pulling direction from the protruding end of the cover closest to the transport surface for transporting the printing medium drawn out from the roll housed in the housing and the transport surface, and above the midpoint in the direction of gravity between the protruding end and the transport surface, and in contact with the outer circumferential surface of the roll as it moves in the pulling direction. (10) The printer according to (6), further comprising: a pivot shaft provided in one of the cover and the main body, which serves as a pivot center for rotating the cover between an open position and a closed position; and an elongated hole provided in the other of the cover and the main body, which receives the pivot shaft so as to be rotatable and movable in the direction that generates the pressing force. (11) The printer according to (6), wherein the guide member has a size and shape that does not contact the cover positioned in the closed position. (12) The printer according to (1), wherein the guide member is provided to be movable in the axial direction in accordance with the axial length of the roll.

Claims

1. A printer comprising: a main body having a storage section for rotatably housing a roll in which a long medium to be printed is wound into a roll; a transport section for pulling the medium to be printed from the roll housed in the storage section and sending it out of the main body; a printing section for printing information on the medium to be printed pulled from the roll by the transport section; a guide member attached to the storage section having a guide surface facing the axial end of the roll, and restricting the axial movement of the roll by bringing the end of the roll into contact with the guide surface; and a projection protruding from the guide surface and positioned on the path of movement of the roll in the pulling direction, so as to restrict the movement of the roll in the pulling direction of the medium to be printed.

2. The printer according to claim 1, wherein the projection is located outside the input path for inserting the unused roll having the maximum diameter into the storage section.

3. The printer according to claim 2, having a cover for opening and closing the housing, wherein the projection is positioned upstream in the pulling direction from the protruding end of the cover closest to the transport surface for transporting the printing medium pulled out from the roll housed in the housing, and in contact with the outer circumferential surface of the roll as it moves in the pulling direction.

4. The printer according to claim 2, having a cover for opening and closing the housing, wherein the projection is positioned above the midpoint in the direction of gravity between the protruding end of the cover closest to the transport surface for transporting the printing medium drawn out from the roll housed in the housing and the transport surface, and in contact with the outer circumferential surface of the roll as it moves in the drawing direction.

5. The printer according to claim 2, having a cover for opening and closing the housing, wherein the projection is positioned upstream in the pulling direction from the protruding end of the cover closest to the transport surface for transporting the printing medium pulled out from the roll housed in the housing, and above the midpoint in the direction of gravity between the protruding end and the transport surface, so as to contact the outer circumferential surface of the roll as it moves in the pulling direction.

6. The printer according to claim 1, having a cover for opening and closing the housing section, the transport section including a platen roller attached to the cover, the printing section having a print head facing the platen roller with the printing medium in between, with the cover positioned in a closed position that closes the housing section, the print head being attached to the main body via a pressure spring that generates a pressing force toward the platen roller, and the cover being movably attached to the main body in the direction that generates the pressing force by the pressure spring.

7. The printer according to claim 6, wherein the projection is positioned upstream in the pulling direction from the protruding end of the cover closest to the transport surface that transports the printing medium pulled out from the roll housed in the housing, and in contact with the outer circumferential surface of the roll as it moves in the pulling direction.

8. The printer according to claim 6, wherein the projection is positioned above the midpoint in the direction of gravity between the protruding end of the cover closest to the transport surface that transports the printing medium drawn out from the roll housed in the housing and the transport surface, and in contact with the outer circumferential surface of the roll as it moves in the drawing direction.

9. The printer according to claim 6, wherein the projection is positioned upstream in the pulling direction from the protruding end of the cover closest to the transport surface that transports the printing medium pulled out from the roll housed in the housing, and above the midpoint in the direction of gravity between the protruding end and the transport surface, so as to contact the outer circumferential surface of the roll as it moves in the pulling direction.

10. The printer according to claim 6, comprising: a pivot shaft provided in one of the cover and the main body, which serves as a pivot center for rotating the cover between an open position and a closed position; and an elongated hole provided in the other of the cover and the main body, which receives the pivot shaft so as to be rotatable and movable in the direction that generates the pressing force.

11. The printer according to claim 6, wherein the guide member has a size and shape that prevents contact with the cover positioned in the closed position.

12. The printer according to claim 1, wherein the guide member is provided so as to be movable in the axial direction in accordance with the axial length of the roll.

Images