Printer

Abstract

To prevent a paper sensor from becoming an obstacle when paper is set in a printer.SOLUTION: A printer 100 includes: a platen roller 62 fixed to a body side; a thermal print head 61 rotatably provided from a position facing the platen roller 62; and a first paper sensor 70 for detecting label paper 201. An arm member 74 is provided on a downstream side in a forward direction in a conveyance direction of the label paper 201 of a position where the platen roller 62 and the thermal print head 61 face each other and rotates according to rotation of the thermal print head 61. A light receiving section 72 to be a part of the first paper sensor 70 is provided in the arm member 74.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a printer.

Background Art

[0002] In thermal transfer printers and thermal printers, a sheet of paper is sandwiched between a platen roller and a printing head that generates heat, and the paper is conveyed by rotating the platen roller. Some printers also use label paper. Label paper is formed by attaching labels to a backing paper that extends long in the conveyance direction with an adhesive.

[0003] When a printer prints on label paper, the printer needs to know the position of the label relative to the print head, and a sensor for detecting the label (hereinafter referred to as a paper sensor) is provided on the conveyance path of the label paper. The paper sensor may be arranged downstream in the paper feed direction from the printing section where the platen roller and the print head face each other (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, in a configuration where the paper sensor is arranged downstream in the paper feed direction from the printing section, when setting the paper in the printer, in order to prevent the leading edge of the paper passing through the printing section from being caught by the paper sensor and causing paper jams, it is appropriate to temporarily retract the paper sensor from the printing section and return the paper sensor to its original position after setting the paper.

[0006] The present invention has been made in view of the above circumstances, and an object thereof is to provide a printer capable of preventing a paper sensor from getting in the way when setting paper in the printer.

Means for Solving the Problems

[0007] The present invention includes a platen roller fixed to the main body side, a print head rotatably provided at a position facing the platen roller, and a paper sensor for detecting paper, and is provided downstream in the paper feeding direction from the position where the platen roller and the print head face each other. It is a printer having an arm member that rotates in response to the rotation of the print head, and at least a part of the paper sensor is provided on the arm member.

Effects of the Invention

[0008] The printer according to the present invention can prevent the paper sensor from getting in the way when setting paper in the printer.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Mode for Carrying Out the Invention

[0010] Embodiments of the printer according to the present invention will be described as follows with reference to the drawings.

[0011] [Embodiment 1] (Overall Configuration) FIGS. 1 and 2 are perspective views showing the overall appearance of the printer 100. FIG. 1 is a perspective view in a state where the cover 12 is closed, FIG. 2 is a perspective view in a state where the cover 12 is open, FIG. 3 is a perspective view in a state where the print head unit 41 is further opened from FIG. 2, and FIG. 4 is a cross-sectional view showing a cross-section by a vertical plane including the front-rear direction L in FIG. 1. The illustrated printer is Embodiment 1 of the printer according to the present invention.

[0012] As shown in FIG. 1, inside the housing 10 which is formed in a rectangular parallelepiped shape as a whole, various functional components are arranged. The housing 10 is configured by covering a case 11 on the lower side in the height direction H with an upper cover 12. The cover 12 opens by rotating upward and rearward about an axis C1 extending along the width direction W at the rear part in the front-rear direction L from the closed state shown in FIG. 1 as shown in FIG. 2. In the state where the cover 12 is open, the inside of the printer 100 can be exposed. On the front surface of the housing 10, at the boundary between the case 11 and the cover 12, an elongated rectangular paper discharge port 13 extending in the width direction W is open.

[0013] The printer 100 includes a paper storage chamber 30, a ribbon storage chamber 40, a printing unit 60, a first paper sensor 70, a second paper sensor 50, and a control unit (not shown).

[0014] (Ribbon storage chamber) As shown in FIGS. 2 and 4, a print head unit 41 is provided in the ribbon storage chamber 40. The print head unit 41 is provided with a thermal print head 61 of the printing unit 60, and has a ribbon drive unit that sets the ribbon unit 300 in a predetermined position and feeds out the ribbon 303 of the ribbon unit 300.

[0015] The print head unit 41 opens by rotating upward and leftward by a predetermined angle β (see FIG. 5 described later) about an axis C2 extending along the front-rear direction L at the left part in the width direction W from the closed state shown in FIG. 2 as shown in FIG. 3. The state where the print head unit 41 rotates by a predetermined angle β from the closed state is an open state. The position of the print head unit 41 in the closed state is defined as the closed position, and the position of the print head unit 41 in the state where it rotates by a predetermined angle β from the closed position and opens is defined as the open position. The print head unit 41 is rotatable between the closed position and the open position. When the print head unit 41 is in the open position, the paper storage chamber 30 is completely exposed, and the roll paper 200 can be inserted into and removed from the paper storage chamber 30.

[0016] As shown in FIG. 4, the print head unit 41 has a thermal print head 61 and, as a ribbon driving unit, includes a feeding-side ribbon holder 42, a take-up-side ribbon holder 43, and a ribbon path 44. The feeding-side ribbon holder 42 and the take-up-side ribbon holder 43 are each formed in a cylindrical shape and are rotationally driven about an axis by a control unit. The feeding-side ribbon holder 42 has a ribbon roll 301 (to be described later) mounted on its outer peripheral surface, and the take-up-side ribbon holder 43 has an empty roll 302 (to be described later) mounted on its outer peripheral surface. The ribbon path 44 is a path through which the ribbon 304 passes. The thermal print head 61 is disposed in the ribbon path 44.

[0017] As shown in FIG. 4, the ribbon unit 300 includes a ribbon roll 301 around which a long unused ribbon 303 is wound in a roll shape, and an empty roll 302 around which the ribbon 303 unwound from the ribbon roll 301 is wound.

[0018] As shown in FIG. 4, the ribbon roll 301 is mounted on the feeding-side ribbon holder 42, the empty roll 302 is mounted on the take-up-side ribbon holder 43, the outermost peripheral portion of the ribbon 303 wound around the ribbon roll 301 is pulled out from the ribbon roll 301, the pulled-out ribbon 303 is arranged along the lower side of the ribbon path 44 to the empty roll 302, and the tip of the pulled-out ribbon 303 is fixed to the empty roll 302, whereby the ribbon unit 300 is set in the print head unit 41.

[0019] The feeding-side ribbon holder 42 and the take-up-side ribbon holder 43 rotate in the direction of winding the ribbon 303 around the empty roll 302 under the control of a control unit (not shown), so that the ribbon 303 wound around the ribbon roll 301 is unwound and is wound around the empty roll 302 via the ribbon path 44 provided with the thermal print head 61.

[0020] When passing through the thermal print head 61, the speed of the ribbon 303 is controlled to be the same as the speed of the label paper 201 when transporting the position of the thermal print head 61 in the forward direction while the ribbon 303 is superposed thereon. The forward direction corresponds to the conveyance direction (feeding direction) when printing on the label paper 201, and is the direction in which the label paper 201 is discharged from the paper discharge port 13 (see FIGS. 1, 2, and 4).

[0021] Further, the feeding-side ribbon holder 42 and the take-up-side ribbon holder 43 rotate in the direction of winding the ribbon 303 around the ribbon roll 301 under the control of a control unit (not shown), so that the ribbon 303 wound around the empty roll 302 is unwound and wound back around the ribbon roll 301 via the ribbon path 44.

[0022] When passing through the thermal print head 61 in the rewinding direction, the speed of the ribbon 303 is controlled to be the same as the speed of the label paper 201 when transporting the position of the thermal print head 61 in the reverse direction (backfeed) while the ribbon 303 is superposed thereon. The reverse direction is the direction opposite to the forward direction and corresponds to the conveyance direction for rewinding the label paper 201 around the roll paper 200.

[0023] (Paper storage chamber) As shown in FIGS. 3 and 4, the paper storage chamber 30 houses a roll paper 200 around which a long label paper 201 is wound in a roll shape. As shown in FIGS. 2 and 4, when the print head unit 41 is closed, the paper storage chamber 30 is partially blocked by the print head unit 41, so that it is not possible to take in and out the roll paper 200 from the paper storage chamber 30, or to pull out the label paper 201 from the roll paper 200 and set it in the printing unit 60.

[0024] On the one hand, as shown in FIG. 3, when the print head unit 41 is open to the upper left, the roll paper 200 can be inserted into and removed from the paper storage chamber 30 without being obstructed by the print head unit 41, and the label paper 201 can be pulled out from the roll paper 200 and set in the printing unit 60.

[0025] As shown in FIG. 3, the label paper 201 wound as the roll paper 200 is formed by arranging a large number of labels 203 side by side in the longitudinal direction on a single base paper 202 continuous in the longitudinal direction. The label 203 is attached to the base paper 202 so as to be disposed on the outer peripheral surface side of the roll of the roll paper 200 with respect to the base paper 202.

[0026] The label paper 201 is provided with a gap of a slight dimension between adjacent labels 203 along the longitudinal direction in which the labels 203 are arranged, and only the base paper 202 exists in this gap. That is, in the portion where the label 203 exists, the label 203 and the base paper 202 are overlapped in the thickness direction, while in the gap portion where the label 203 does not exist, only the base paper 202 exists in the thickness direction.

[0027] Therefore, when the label paper 201 is irradiated with light from one surface side in the thickness direction by a transmissive optical sensor, a significant difference in the amount of transmitted light detected on the opposite surface side of the label paper 201 can be detected between the portion where the label 203 exists and the portion where the label 203 does not exist. The first paper sensor 70 described later is this transmissive optical sensor.

[0028] The roll paper 200 housed in the paper storage chamber 30 with the print head unit 41 shown in FIG. 3 open to the upper left pulls out the outermost peripheral portion of the wound label paper 201, and the leading end of the pulled-out label paper 201 passes over the platen roller 62 shown in FIG. 4 and is arranged downstream of the peel plate 63 provided on the downstream side in the forward direction from the printing unit 60. Then, with the print head unit 41 shown in FIGS. 2 and 4 closed, the label paper 201 is set in a usable state.

[0029] When the peel plate 63 does not include a peeler unit 80 described later, it can be used as a manual cutter. That is, the label paper 201 printed by the printing unit 60 is stopped being conveyed at the position where only the portion of the backing paper 202 between the rear end of the printed label 203 and the front end of the next label 203 reaches the front end of the peel plate 63 under the control of the control unit. In this state, by holding the printed label paper 201 protruding in the forward direction from the peel plate 63 by hand and pulling it downward obliquely, the label paper 201 (only the portion of the backing paper 202) can be torn off at the edge of the front end of the peel plate 63.

[0030] (Second Paper Sensor) The second paper sensor 50 is provided on the path of the label paper 201 between the paper storage chamber 30 and the printing unit 60 described later. The second paper sensor 50 is provided on the upstream side in the forward direction of the label paper 201 with respect to the printing unit 60. The second paper sensor 50 includes a light source 51 and a reflected light receiving unit 52 provided on the back side of the label paper 201, that is, the lower surface side of the backing paper 202, and a transmitted light receiving unit 53 provided on the front side of the label paper 201, that is, the upper surface side where the label 203 is arranged.

[0031] Not limited to the label paper 201, there is a roll paper 200 stored in the paper storage chamber 30 on the surface opposite to the printed surface of the paper, on which, for example, a black mark serving as the printing reference position of the paper is formed.

[0032] The second paper sensor 50 constitutes a reflection type optical sensor that detects a black mark provided on the back surface of the paper by the combination of the light source 51 and the reflected light receiving unit 52. By detecting the black mark by the second paper sensor 50, the printing reference position of the paper is detected on the upstream side in the forward direction of the paper.

[0033] Further, the second sheet sensor 50 constitutes a transmissive optical sensor that detects the difference in the amount of transmitted light passing through the sheet by combining a light source 51 and a transmitted light receiving unit 53, and detects the leading edge position and the trailing edge position of the label 203 on the upstream side in the forward direction of the label paper 201.

[0034] (Printing section) The printing section 60 includes a thermal print head 61 and a platen roller 62. The thermal print head 61 has a plurality of heating elements arranged side by side along the width direction W, and as described above, is provided in the ribbon path 44 of the print head unit 41. The thermal print head 61 generates heat in a predetermined pattern under the control of the control unit. The platen roller 62 is fixedly disposed on the side of the case 11 (main body side). The platen roller 62 rotates under the control of the control unit so as to drive the label paper 201 in the forward direction or the reverse direction of the conveyance direction.

[0035] When the print head unit 41 is in the closed position, as shown in FIG. 4, the thermal print head 61 is disposed above the platen roller 62, parallel to and in contact with the platen roller 62, and the thermal print head 61 and the platen roller 62 sandwich the ribbon 303 and the label paper 201 in a state of being stacked in the thickness direction. Thereby, the printer 100 brings the ribbon 303 disposed in the ribbon path 44 into close contact with the label 203 of the label paper 201 disposed on the platen roller 62. When the print head unit 41 is in the open position, as shown in FIG. 3, the thermal print head 61 is in a state of being separated from the platen roller 62 and moving away.

[0036] In the state shown in FIG. 4 where the print head unit 41 is in the closed position, under the control of the control unit, while causing the thermal print head 61 to generate heat in a predetermined pattern, the platen roller 62, the supply-side ribbon holder 42, and the take-up-side ribbon holder 43 are rotated so that the label paper 201 and the ribbon 303 move in the forward direction of the conveyance direction. As a result, while the ribbon 303 and the label paper 201 are synchronously fed in the forward direction of the conveyance direction, the ink on the ribbon 303 is transferred to the label 203 in a predetermined pattern, and printing of a predetermined pattern is performed on the label 203.

[0037] (First sheet sensor) FIG. 5 is a perspective view showing the arrangement of the first sheet sensor 70 in a state where the print head unit 41 is open, FIG. 6 is a perspective view showing the arrangement of the first sheet sensor 70 in a state where the print head unit 41 is closed, FIG. 7 is an exploded perspective view showing the arrangement of the light source 71 and the light guide member 73 in the first sheet sensor 70, and FIG. 8 is an exploded perspective view showing the arrangement of the light receiving unit 72 of the first sheet sensor 70.

[0038] Downstream in the forward direction of the conveyance direction of the label paper 201 from the position where the platen roller 62 and the thermal print head 61 face each other, a peel plate 63 is provided in proximity to the platen roller 62. The peel plate 63 is a path member through which the label paper 201 passes, and as described above, it also functions as a manual cutter for manually tearing the printed label paper 201 using the leading edge. The peel plate 63 extends along the width direction W.

[0039] The first sheet sensor 70 includes a light source 71 (light emitting element), a light guide member 73, and a light receiving unit 72 (light receiving element). The light source 71 is, for example, an infrared light emitting diode, but the light source 71 is not limited to an infrared light emitting diode and may be a light source that emits visible light or other light. As shown in FIG. 4, the light source 71 is provided so as to emit infrared rays obliquely upward in front along the top plate portion of the peel plate 63.

[0040] The light guide member 73 is provided obliquely forward and upward from the light source 71 on the peel plate 63. The light guide member 73 is a prism that reflects the infrared rays emitted obliquely forward and upward from the light source 71 upward in the height direction H. As shown in FIGS. 4 to 8, a hole 63a for passing the infrared rays reflected upward by the light guide member 73 is formed in the top plate of the peel plate 63.

[0041] The light receiving part 72 receives infrared rays. When the print head unit 41 shown in FIG. 6 is in the closed position, the light receiving part 72 is disposed above the hole 63a of the peel plate 63 with a slight gap from the peel plate 63. The light receiving part 72 is provided at a position where it can receive the infrared rays reflected by the light guide member 73 and passing through the hole 63a.

[0042] The light receiving part 72 is a photo transistor and is disposed on an arm member 74 that rotates according to the rotation of the print head unit 41 directly above the peel plate 63 as shown in FIGS. 5 to 8. As shown in FIG. 8, the arm member 74 is configured to be rotatable coaxially with the rotation axis C2 of the print head unit 41. The arm member 74 is provided to face the peel plate 63 downstream in the forward direction in the conveyance direction of the label paper 201 from the position of the print part 60 where the platen roller 62 and the print head 61 face each other.

[0043] As shown in FIGS. 5 and 8, a coil spring 75 is disposed on the portion of the arm member 74 on the left side of the axis C2. By pulling the left side portion of the arm member 74 downward, a biasing force that rotates the arm member 74 counterclockwise in the drawing acts on the arm member 74.

[0044] Here, when the print head unit 41 is in the open position, the arm member 74 rotates counterclockwise by the coil spring 75. However, when the arm member 74 rotates by a predetermined angle α with respect to the top plate portion of the peel plate 63 and moves away from the label paper 201 to a position (retracted position), the lower portion 74b on the left side of the arm member 74 abuts against a stopper 65 formed in a convex shape on the base plate 67 of the frame member that forms the skeleton of the printer 100. As a result, the arm member 74 is prevented from rotating counterclockwise by more than the predetermined angle α.

[0045] Note that the predetermined angle α by which the arm member 74 rotates is set to be smaller than (α < β) the predetermined angle β by which the print head unit 41 rotates from the closed position (FIG. 6) to the open position (FIG. 5). As an example, the predetermined angle α is set to approximately 1 / 2 of the predetermined angle β. For example, the predetermined angle α is 35 degrees and the predetermined angle β is 70 degrees.

[0046] As shown in FIGS. 5, 6, and 8, the print head unit 41 is provided with a pressing projection 48. The pressing projection 48 abuts against the upper surface 74a of the arm member 74 that has stopped at the position of the predetermined angle α from above during the process in which the print head unit 41 rotates from the open position to the closed position. Then, while the print head unit 41 rotates from the predetermined angle α to the closed position, the pressing projection 48 continuously presses the upper surface 74a of the arm member 74 downward against the biasing force of the coil spring 75. As a result, the print head unit 41 rotates the arm member 74 clockwise until it is in a posture parallel to the top plate portion of the peel plate 63.

[0047] As described above, when the print head unit 41 rotates to the closed position, the arm member 74 rotates clockwise by the pressing projection 48. However, when the arm member 74 reaches the position (detection position) where it is parallel to the top plate portion of the peel plate 63, as shown in FIG. 6, the lower part 74c on the right side of the arm member 74 abuts against the stopper 66 formed on the peel plate 63. Thereby, the arm member 74 is prevented from rotating in the clockwise direction beyond the position where it is parallel to the top plate portion of the peel plate 63.

[0048] Therefore, the arm member 74 stops at the position where it is parallel to the top plate portion of the peel plate 63. When the arm member 74 is in the position where it is parallel to the top plate portion of the peel plate 63, the light receiving portion 72 receives the infrared rays that are reflected by the light guiding member 73 and pass through the hole 63a. Therefore, the position where the arm member 74 is parallel to the top plate portion of the peel plate 63 is set as the detection position of the first sheet sensor 70.

[0049] When the arm member 74 rotates counterclockwise from the position where it is parallel to the top plate portion of the peel plate 63, the light receiving portion 72 is out of the irradiation range of the infrared rays reflected by the light guiding member 73, so the light receiving portion 72 cannot detect the infrared rays.

[0050] As described above, the arm member 74 rotates in response to the rotation of the print head unit 41. Specifically, the pressing projection 48 provided on the print head unit 41 and the coil spring 75 constitute an interlocking mechanism that rotates the arm member 74 between the detection position close to the label paper 201 and the retracted position away from the label paper 201 in conjunction with the rotation of the print head unit 41.

[0051] Thus, in order to pull out the label paper 201 from the roll paper 200 stored in the paper storage chamber 30 and set it to the position of the peel plate 63, when the print head unit 41 covering the path of the label paper 201 is flipped up (rotated) to a position at a predetermined angle β (open position), the pressing protrusion 48 and the coil spring 75 provided on the print head unit 41 flip up the arm member 74 covering above the peel plate 63 to a position at a predetermined angle α (retracted position) away from the label paper 201.

[0052] As a result, as shown in FIG. 5, the arm member 74 retracts above the peel plate 63 where the label paper 201 is disposed, and a space S1 at a predetermined angle α is formed below the arm member 74. Thereby, during the operation of setting the label paper 201 above a part of the space S1, i.e., above the peel plate 63, the arm member 74 does not get in the way, and the operation of setting the label paper 201 can be facilitated.

[0053] Also, since the arm member 74 is disposed to face the peel plate 63 above the peel plate 63, it is provided on the downstream side in the conveyance direction of the label paper 201 than the thermal print head 61 disposed to face the platen roller 62 above the platen roller 62.

[0054] And the ribbon 303 needs to be disposed to the downstream side in the conveyance direction than the thermal print head 61 in the ribbon path 44. However, if the arm member 74 is formed to rotate integrally with the print head unit 41 up to a predetermined angle β, the arm member 74 is disposed immediately in front of the ribbon path 44 of the print head unit 41 in the open position, and the arm member 74 gets in the way when setting the ribbon 303.

[0055] However, in the printer 100 of the present embodiment, the print head unit 41 stops at a position rotated by a predetermined angle β (open position), and the arm member 74 stops at a position rotated by a predetermined angle α smaller than the predetermined angle β (retracted position) by the stopper 65. Therefore, the arm member 74 does not exist immediately in front of the ribbon path 44 of the print head unit 41 in the open position, and a space S2 of an angle (β−α) of the difference between the rotation angles of the two is formed at the lower right of the print head unit 41.

[0056] Accordingly, when attaching the ribbon roll 301 and the empty roll 302 to the print head unit 41 and setting the ribbon 303 through the lower surface side of the ribbon path 44 which is a part of the space S2, the arm member 74 does not get in the way, and the work of setting the ribbon unit 300 can be facilitated.

[0057] Also, when the print head unit 41 is in the open position, although the arm member 74 is also rotated to the position of the predetermined angle α, against the biasing force of the coil spring 75 while keeping the print head unit 41 in the open position, the arm member 74 can be pushed and rotated to the detection position facing the peel plate 63.

[0058] Therefore, when setting the ribbon 303 through the lower surface side of the ribbon path 44, if the space of the above-described difference angle (β−α) is insufficient, the space below the lower right of the print head unit 41 can be secured wider by rotating the arm member 74 downward.

[0059] The specific angles of the predetermined angle α by which the arm member 74 rotates and the predetermined angle β by which the print head unit 41 rotates in the printer 100 are not limited to the combination of 35 degrees and 70 degrees described above, and the ratio of the predetermined angle α to the predetermined angle β is also not limited to 1:2 described above.

[0060] That is, the predetermined angle α in the printer 100 may be any angle as long as the space formed below the arm member 74 does not obstruct the operation of setting the label paper 201 above the peel plate 63. Also, the predetermined angle α may be any angle as long as the space formed below the print head unit 41 does not obstruct the operation of setting the ribbon 303 when the arm member 74 does not get in the way.

[0061] FIG. 9 is a cross-sectional view showing a cross-section taken along a vertical plane along the front-rear direction L for explaining a structure that prevents the arm member 74 from swinging in the front-rear direction L.

[0062] As shown in FIG. 6, the arm member 74 is pivotally supported on the shaft C2 in a state where its rear surface is in close contact with the front surface of the base plate 67. As shown in FIGS. 5 and 7, the peel plate 63 is formed with a vibration-damping piece 63b that protrudes upward. When the arm member 74 is in the detection position facing the peel plate 63 shown in FIG. 6, the vibration-damping piece 63b is arranged such that, as shown in FIG. 9, the vibration-damping piece 63b contacts or is close to the arm member 74 from the front side in the front-rear direction L.

[0063] Thereby, the vibration-damping piece 63b prevents the arm member 74 at the detection position from swinging forward. Also, since the rear surface of the arm member 74 is in close contact with the front surface of the base plate 67, the arm member 74 is prevented from swinging backward. Therefore, it is possible to prevent the light reception of the light receiving portion 72 from becoming unstable due to the arm member 74 swinging in the front-rear direction at the detection position.

[0064] In the printer 100 of the present embodiment, with the ribbon unit 300 set on the print head unit 41 and the label paper 201 set on the platen roller 62 and the peel plate 63, the print head unit 41 is rotated to the closed position, so that, as shown in FIG. 4, the ribbon 303 and the label paper 201 are sandwiched between the thermal print head 61 and the platen roller 62 in a state of being overlapped in the thickness direction.

[0065] Also, directly above the label paper 201 disposed on the peel plate 63 provided with the light source 71 and the light guide member 73 of the first paper sensor 70, a light receiving portion 72 is disposed on the arm member 74 to receive the transmitted light that has passed through the label paper 201. Thereby, the first paper sensor 70 can detect whether the portion of the label paper 201 that has passed through the position where the first paper sensor 70 is provided is a portion where the label 203 is attached to the backing paper 202 or a portion of only the backing paper 202 without the label 203, based on the difference in the amount of transmitted light detected by the light receiving portion 72.

[0066] Here, before the start of printing by the printing unit 60, when the printer 100 detects that the portion of the label paper 201 detected by the first paper sensor 70 provided on the downstream side in the conveyance direction of the label paper 201 from the printing unit 60 is a portion of only the backing paper 202, the control unit rotates the platen roller 62 in the forward direction to further feed the label paper 201 in the forward direction of the conveyance direction.

[0067] Then, when the first paper sensor 70 detects the boundary where the portion changes from only the backing paper 202 to the portion where the label 203 is attached to the backing paper 202 due to the difference in the amount of received transmitted light, the position of the leading end of the label 203 in the conveyance direction is detected. Therefore, after stopping the rotation of the platen roller 62, the control unit rotates the platen roller 62 in the opposite direction so as to pull back (back-feed) the detected leading end of the label 203 to the position of the printing unit 60.

[0068] Note that since the length from the position of the first paper sensor 70 to the printing unit 60 along the conveyance direction of the label paper 201 is measured in advance and is known, the control unit rotates the platen roller 62 so as to back-feed the label paper 201 by that known length.

[0069] On the one hand, before the start of printing by the printing unit 60, when the control unit detects that the portion of the label paper 201 detected by the first paper sensor 70 provided on the downstream side of the printing unit 60 in the conveyance direction of the label paper 201 is the portion where the label 203 is attached to the backing sheet 202, the control unit rotates the platen roller 62 in the opposite direction to pull back the label paper 201 in the direction opposite to the forward direction of the conveyance direction.

[0070] Then, when the first paper sensor 70 detects the boundary where the amount of transmitted light received switches from the portion where the label 203 is attached to the backing sheet 202 to the portion of only the backing sheet 202, the position of the leading end of the label 203 in the conveyance direction is detected. Therefore, the control unit continues to rotate the platen roller 62 in the opposite direction so as to pull back the detected leading end of the backing sheet 202 to the position of the printing unit 60.

[0071] Based on the above control based on the detection result of the first paper sensor 70 provided on the downstream side of the printing unit 60 in the conveyance direction of the label paper 201, the printer 100 can also perform printing on the label 203 provided at the leading end of the label paper 201 unwound from the roll paper 200, and does not waste the first label 203 provided on the leading end side of the label paper 201.

[0072] The printer 100 has been described with the first paper sensor 70 as a transmissive optical sensor having a light source 71 arranged to sandwich the label paper 201 vertically and a light receiving unit 72 for detecting the amount of transmitted light. However, the first paper sensor 70 may be configured to include both a transmissive optical sensor and a reflective optical sensor, similar to the second paper sensor 50, or may be configured to include only a reflective optical sensor.

[0073] When the printer 100 is configured such that the first paper sensor 70 is a reflection-type optical sensor, a light source 71 and a light-receiving unit that detects the print reference position of the paper according to the amount of reflected light reflected by the label paper 201 may be provided on the arm member 74. Alternatively, the printer 100 may be configured such that a light source 71 and a light-receiving unit that detects the print reference position of the paper according to the amount of reflected light reflected by the label paper 201 are provided on the peel plate 63.

[0074] When the printer 100 is configured such that the first paper sensor 70 is a reflection-type optical sensor and a transmission-type optical sensor, a light source 71 and a light-receiving unit that detects the print reference position of the paper according to the amount of reflected light reflected by the label paper 201 are provided on the arm member 74, and a light-receiving unit 72 that detects the label according to the amount of transmitted light transmitted through the label paper 201 is provided on the peel plate 63. In this case, the light source 71 and the light-receiving unit 72 are opposite to the arrangement shown in FIG. 4. Alternatively, the printer 100 may be configured such that a light source 71 and a light-receiving unit that detects the print reference position of the paper according to the amount of reflected light reflected by the label paper 201 are provided on the peel plate 63, and a light-receiving unit 72 that detects the label according to the amount of transmitted light transmitted through the label paper 201 is provided on the arm member 74.

[0075] The configurations and arrangement variations of the first paper sensor 70 described above are similarly applicable in the modification examples described below.

[0076] [Modification Example 1] FIG. 10 is a cross-sectional view corresponding to FIG. 4 showing the printer 400 of Modification Example 1, and FIG. 11 is a perspective view showing the appearance of a portion where the peeler unit 80 is mounted in the printer 400 of Modification Example 1. The printer 100 of Embodiment 1 does not include the peeler unit 80, but the printer 400, which is a modification example of the printer 100, is obtained by mounting the peeler unit 80 on the printer 100.

[0077] As shown in FIGS. 10 and 11, the peeler unit 80 has a path at the tip of the peel plate 63 for bending and conveying the backing paper 202 downward and rearward at an acute angle, and automatically peels the label 203 discharged from the paper discharge port 13 without bending at the tip of the peel plate 63 from the backing paper 202.

[0078] As shown in the figure, the peeler unit 80 is disposed in the space below the peel plate 63. Therefore, it is difficult to secure a space below the peel plate 63 for arranging the light source 71 directly below the light receiving portion 72 in a posture of emitting infrared rays upward toward the light receiving portion 72 disposed above in the height direction H.

[0079] However, in the printer 400 of Modification 1, instead of disposing the light source 71 directly below the light receiving portion 72, the light source 71 is disposed upstream in the forward direction from the light receiving portion 72, so that the space below occupied by the peel plate 63 is minimized, and the infrared rays emitted forward and upward from the light source 71 are reflected by the light guide member 73 to the light receiving portion 72, thereby enabling detection of the label 203 on the label paper 201.

[0080] In addition to the above-described effects, the printer 400 of Modification 1 also exhibits the effects exhibited by the printer 100 of Embodiment 1.

[0081] [Modification 2] FIGS. 12 and 13 are perspective views showing the interlocking mechanism in the printer 500 of Modification 2, where FIG. 12 shows the state when the print head unit 41 is in the closed position, and FIG. 13 shows the state when the print head unit 41 is in the open position.

[0082] The printer 100 of Embodiment 1 applies a pressing projection 48 and a coil spring 75 as an interlocking mechanism that rotates the arm member 74 in conjunction with the rotation of the print head unit 41. However, the printer 500, which is a modified example of the printer 100, applies a gear train consisting of three gears 68a, 68b, and 68c as the interlocking mechanism. Further, the gear 68b is a two-stage gear in which two gears are stacked one above the other along the axial direction. The two gears constituting the gear 68b are coaxial and have different numbers of teeth (radii of pitch circles).

[0083] The gear 68a is fixed to the shaft C2 that rotates the print head unit 41 and rotates integrally with the rotation of the print head unit 41. The gear 68a has teeth formed only in an angular range corresponding to a predetermined angle β that is the rotation range of the print head unit 41. The gear 68c is provided at the rotation center of the arm member 74, and when the gear 68c rotates, the arm member 74 is rotated integrally with the gear 68c. The gear 68b is a gear that mediates between the gear 68a and the gear 68c with two-stage gears, transmits the rotation of the gear 68a to the gear 68c, and transmits the rotation of the gear 68c to the gear 68a.

[0084] Specifically, the gear 68a meshes with the gear among the two gears constituting the gear 68b that has fewer teeth and a smaller pitch circle, and the gear 68c meshes with the gear among the two gears constituting the gear 68b that has more teeth and a larger pitch circle.

[0085] Via the three gears 68a, 68b, and 68c, the arm member 74 rotates in conjunction with the print head unit 41, so the arm member 74 is interlocked to rotate in the same direction as the print head unit 41. Further, the gear train consisting of the gears 68a, 68b, and 68c is formed such that the input / output gear ratio is 1:1.95. In conjunction with the print head unit 41 rotating by a predetermined angle β from the closed position shown in FIG. 12 to the open position shown in FIG. 13, the arm member 74 rotates by a predetermined angle γ from the detection position shown in FIG. 12 to the retracted position shown in FIG. 13.

[0086] Here, a predetermined angle γ, which is the rotation angle of the arm member 74, is 1.95 times the angle of the predetermined angle β according to the gear ratio of the input and output of the gear train that is the interlocking mechanism described above.

[0087] Thus, in the printer 500 of Modification 2, when the print head unit 41 is in the open position, the arm member 74 also retracts above the peel plate 63 on which the label paper 201 is disposed, and a space of a predetermined angle γ is formed below the arm member 74. Thereby, when setting the label paper 201 above the peel plate 63, the arm member 74 does not get in the way, and the work of setting the label paper 201 can be facilitated.

[0088] Further, the arm member 74 stops at a position rotated to a predetermined angle γ (retracted position) exceeding the open position (predetermined angle β) of the print head unit 41. Therefore, the arm member 74 does not exist on the downstream side in the conveyance direction of the print head unit 41 in the open position, and moreover, a space of a predetermined angle β is formed in the lower right of the print head unit 41.

[0089] Thereby, when attaching the ribbon roll 301 and the empty roll 302 to the print head unit 41 and setting the ribbon 303 through the lower surface side of the ribbon path 44, the arm member 74 does not get in the way, and the work of setting the ribbon unit 300 can be facilitated.

[0090] Note that the gear ratio of the input and output of the gear train composed of the gears 68a, 68b, and 68c constituting the interlocking mechanism is not limited to the example of Modification 2 described above, and at least in the same manner as the printer of Embodiment 1, when attaching the ribbon roll 301 and the empty roll 302 to the print head unit 41 and setting the ribbon 303 through the lower surface side of the ribbon path 44, it may be stopped at a position where the arm member 74 does not get in the way.

[0091] In addition to the above-described effects, the printer 500 of Modification 2 also exhibits the effects exhibited by the printer 100 of Embodiment 1.

[0092] The printers 100, 400, and 500 of the above-described Embodiment 1 and Modification Examples 1 and 2 are thermal transfer printers that include a ribbon unit 300 in a ribbon storage chamber 40 and perform printing by thermally transferring the ink of a ribbon 303 onto a label 203 of a label paper 201. However, these printers 100, 400, and 500 can also perform printing without using the ribbon unit 300.

[0093] That is, the printers 100, 400, and 500 can apply thermal paper as the roll paper 200 without setting the ribbon unit 300 in the ribbon storage chamber 40. In this case, the printers 100, 400, and 500 can perform printing on the thermal paper by the thermal paper coloring due to the heat emitted by the thermal print head 61, and the printers 100, 400, and 500 function as thermal printers.

[0094] [Modification Example 3] FIG. 14 is a perspective view showing the printer 600 of Modification Example 3, and FIG. 15 is a perspective view showing an arm member 174 in the printer 600 of Modification Example 3.

[0095] The above-described printers 100, 400, and 500 are thermal transfer printers, but the illustrated printer 600 is a thermal printer which is Modification Example 3 of the printer 100. That is, since the printer 600 does not use the ribbon unit 300, unlike the printer 100, it does not have a ribbon storage chamber 40. Therefore, the print head unit 141 provided with the thermal print head 61 of the printer 600 does not have a ribbon drive unit.

[0096] Since the printer 600 does not have the ribbon unit 300 as described above, there is no operation of arranging the ribbon 303, and the arm member 74 does not get in the way in relation to the print head unit 141. For this reason, in the printer 600, as shown in FIGS. 14 and 15, an arm member 174 provided with a light receiving portion 72 of the first paper sensor 70 is fixed to the print head unit 141.

[0097] That is, the arm member 174 rotates integrally in response to the rotation of the print head. Therefore, when the predetermined angle of rotation of the print head unit 141 is β, the predetermined angle of rotation of the arm member 174 is also β.

[0098] In this way, in the printer 600 of the third modification, when the print head unit 141 is in the open position, the arm member 174 also retracts above the peel plate 63 on which the label paper 201 is disposed, and a space of a predetermined angle β is formed below the arm member 174. Thereby, when setting the label paper 201 above the peel plate 63, the arm member 174 does not get in the way, and the work of setting the label paper 201 can be facilitated.

[0099] The printers 100, 400, 500, and 600 of Embodiment 1 and each modification include the second paper sensor 50, but the printer according to the present invention may not include the second paper sensor 50, and it is sufficient to include the first paper sensor 70 as the paper sensor.

[0100] The printers 100, 400, 500, and 600 of Embodiment 1 and each modification apply label paper 201 and thermal paper as the paper accommodated in the paper accommodation chamber 30, and the first paper sensor 70 has been described as detecting the label 203 of the label paper 201 or a specific mark of the thermal paper. However, the printer according to the present invention is not limited to using label paper 201 or thermal paper and detecting a specific mark of the label of the label paper 201 or the thermal paper. Therefore, the printer according to the present invention may use other types of paper other than label paper and thermal paper, and the first paper sensor 70 may detect the other type of paper.

Explanation of Signs

[0101] 41 Print head unit 61 Thermal print head 62 Platen roller 63 Peel plate 70 First paper sensor 71 Light source 72 Light receiving part 73 Light guide member 74 Arm member 100 Printer 201 Label paper H Height direction L Front-back direction W Width direction

Claims

1. a platen roller fixed to the main body side, a print head rotatably provided at a position facing the platen roller, a paper sensor for detecting paper, and comprising, an arm member that is provided downstream of the position where the platen roller and the print head face each other in the paper feeding direction, and rotates in accordance with the rotation of the print head, a printer in which at least a part of the paper sensor is provided on the arm member.

2. the print head is rotatable between a closed position where the print head is close to and faces the platen roller and an open position where the print head is away from the platen roller, the printer according to claim 1, further comprising an interlocking mechanism that rotates the arm member in conjunction with the rotation of the print head between a detection position close to the paper corresponding to the closed position and a retracted position away from the paper corresponding to the open position.

3. the interlocking mechanism is configured such that an angle of rotation between the detection position and the retracted position is smaller than an angle of rotation between the closed position and the open position, and a space along the direction of rotation is formed between the arm member disposed at the retracted position and the print head disposed at the open position, the printer according to claim 2.

4. the interlocking mechanism is configured such that an angle of rotation from the detection position to the retracted position is set to be larger than an angle of rotation from the closed position to the open position, the printer according to claim 2.

5. the interlocking mechanism is configured to allow the arm member to rotate from the retracted position toward the detection position in a state where the print head is disposed at the open position, the printer according to claim 2.

6. the paper sensor is an optical sensor having a light emitting element and a light receiving element, the printer according to any one of claims 1 to 5, wherein one of the light emitting element and the light receiving element is disposed on the arm member, and the other element is disposed on a path member through which the paper passes and provided downstream of the platen roller together with a light guide member.

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