Printer and mounting unit

Abstract

To provide a printer and a mounting unit which contribute to suppression of erroneous detection of a medium.SOLUTION: A heat-sensitive label 8 is conveyed on a conveyance path T4, and is mounted on a guide rib 36 provided on the upper wall. A sensor unit 40 exposed to the opening of the upper wall has a holder 45 and a sensor substrate 42 mounted with an optical sensor 41. The holder 45 is formed by integrally molding a support part 46 and a detection part 47 using an acrylic resin. The acrylic resin has a filter function, and characteristics such that transmittance of light at a wavelength of less than 900 nm is lower than transmittance of light at a wavelength of 900 nm or more. Visible light is within a wavelength range of 400 nm to 700 nm, and detection light X emitted by the light-emitting part of the optical sensor 41 has high relative output in a wavelength range of 900 nm to 1,000 nm. The holder 45 suppresses an influence of disturbance light. Other component is not interposed between the optical sensor 41 and a transmission part 47C transmitting an optical path L therethrough, and variations in a distance are suppressed.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to a printer and a mounting unit. [Background technology]

[0002] The optical sensor described in Patent Document 1 includes a light receiving element and is covered with a light-transmitting case. A light-shielding sticker is attached to the surface of the case facing the light receiving element. The sticker has a hole for passing the sensor light. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 8-330608 Summary of the Invention [Problem to be solved by the invention]

[0004] For example, the optical sensor may be used in a printer to detect a medium printed by the printer. Since the optical sensor has a hole in the seal and the case is translucent, sunlight may enter the case through the hole in the seal. Therefore, the optical sensor may erroneously detect the medium due to the influence of sunlight.

[0005] An object of the present invention is to provide a printer and a mounting unit that contribute to reducing erroneous detection of a medium. [Means for solving the problem]

[0006] According to a first aspect of the present invention, there is provided a printer that prints on a medium, comprising: a determining member that determines a transport path for the medium; a light-emitting unit that faces the transport path and emits sensor light having a wavelength of 900 nm or more; a light-receiving unit that faces the transport path and receives the sensor light emitted by the light-emitting unit, and includes an optical sensor that detects the medium on the transport path; a support unit that supports the optical sensor; and a holder that includes a filter plate that is positioned on the optical path of the sensor light from the light-emitting unit and extends so as to intersect with the optical path, and is characterized in that, in the optical path direction along the optical path, the transmittance of light with a wavelength of less than 900 nm through the filter plate is lower than the transmittance of light with a wavelength of 900 nm or more through the filter plate.

[0007] According to the first aspect, the filter plate blocks a portion of the light with wavelengths less than 900 nm that is directed to the light receiving section, thereby reducing the amount of disturbance light, such as sunlight, received by the light receiving section, thereby enabling the printer to reduce erroneous detection of the medium.

[0008] In the first aspect, the area of ​​the filter plate on both sides in the optical path direction through which the sensor light passes may be flat. In this case, scattering of the sensor light passing through the filter plate is suppressed. Thus, the printer can further suppress erroneous detection of the medium.

[0009] In a first aspect, the regulating member includes an extension plate extending in a direction intersecting the optical path direction and having an opening, and a protrusion protruding from the extension plate toward the transport path in the optical path direction and supporting the medium on the transport path, and the holder is fixed to the regulating member with the filter plate disposed in the opening, and the surface of the filter plate facing the transport path may be located in the optical path direction from the tip of the protrusion toward the extension plate, rather than the tip of the protrusion. In this case, the medium is prevented from coming into contact with the filter plate. Therefore, the printer can prevent the filter plate from becoming dirty or damaged.

[0010] The optical sensor of the first aspect may be a reflective sensor including the light emitting portion and the light receiving portion. In this case, the printer supports the light emitting portion and the light receiving portion with a single holder. Therefore, the printer can be made compact.

[0011] In the first aspect, the holder may be integrally formed by the support portion and the filter plate. In this case, the printer can suppress variation in the distance between the filter plate and the optical sensor in the light path direction.

[0012] According to a second aspect of the present invention, there is provided a printer having a housing that houses a printing unit that prints on a medium, the mounting unit being mounted on a surface of the housing that has an outlet through which the medium printed by the printing unit is discharged, the mounting unit being provided with a defining member that defines a transport path for the medium discharged from the outlet, a light-emitting unit facing the transport path and emitting sensor light having a wavelength of 900 nm or more, a light-receiving unit facing the transport path and receiving the sensor light emitted by the light-emitting unit, an optical sensor that detects the medium on the transport path, a support unit that supports the optical sensor, and a holder that is disposed on the optical path of the sensor light emitted by the light-emitting unit and extends so as to intersect with the optical path, the transmittance of light of wavelengths less than 900 nm in the filter plate is lower than the transmittance of light of wavelengths equal to or greater than 900 nm in the filter plate in the optical path direction along the optical path. Thus, the second aspect has the same effect as the first aspect. [Brief description of the drawings]

[0013] [Figure 1] FIG. 2 is a perspective view of the printer 1 with the cover 12 closed. [Diagram 2] FIG. 2 is a perspective view of the printer 1 with the cover 12 open. [Diagram 3] FIG. 2 is a perspective view of the printer 1 with the peeler unit 30 attached. [Figure 4] 4 is a cross-sectional view of the peeler unit 30 taken along line II in FIG. 3 . [Diagram 5]FIG. 2 is a perspective view of the sensor unit 40. [Figure 6] 6 is a cross-sectional view of the sensor unit 40 taken along line II-II in FIG. 5. FIG. [Figure 7] 2 is a perspective view of a sensor board 42 on which an optical sensor 41 is mounted and a holder 45. FIG. [Figure 8] 1 is a graph showing the relationship between wavelength and light energy in sunlight. [Figure 9] 1 is a graph showing the relationship between wavelength and relative output in detected light. [Figure 10] 1 is a graph showing the relationship between the wavelength of light and the transmittance in an acrylic resin. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] An embodiment of the present invention will be described with reference to the drawings. The drawings are used to explain technical features that may be adopted by the present invention. In other words, the configurations and the like shown in the drawings are not intended to be limiting, but are merely illustrative examples. In the description of this embodiment, the upper left, lower right, lower left, upper right, upper, and lower in FIG. 1 correspond to the left, right, front, rear, upper, and lower of the printer 1. Also, the orientation of the peeler unit 30, which will be described later, follows the orientation of the printer 1 when it is attached to the printer 1 (see FIG. 3).

[0015] The printer 1 is a portable printing device configured to be capable of printing on a print medium. The print medium is, for example, a die-cut thermal label 8. As shown in Figs. 1 and 2, the printer 1 has a housing 10. The housing 10 is substantially rectangular and has a main body 11, a cover 12, and a discharge section 15. The main body 11 and the cover 12 are formed of, for example, a resin material. The discharge section 15 is a section that discharges the print medium printed inside the printer 1 to the outside of the printer 1, and is formed between the front surface of the main body 11 and the front surface of the cover 12, and extends in the left-right direction.

[0016] The main body 11 is in the shape of a substantially rectangular box. The main body 11 constitutes the lower part of the printer 1. The main body 11 includes a handle 16, a storage section 21, a platen roller 22, and a roll support section 23. The handle 16 is a grip for carrying the printer 1, and is rotatably supported at a position near the front of the upper part of both the left and right walls of the main body 11. The storage section 21 is an internal space of the printer 1, and can store a label roll (not shown) with its core extending in the left-right direction. The label roll is formed, for example, by winding a long label sheet 7 (see FIG. 4) with a plurality of thermal labels 8 attached to a mount 9 around a cylindrical core. The platen roller 22 is a cylindrical roller for transporting the print medium, and is provided at the front of the main body 11 along the longitudinal direction (left-right direction) of the discharge section 15. The platen roller 22 rotates when a drive motor (not shown) is driven. The storage unit 21 is located behind the discharge unit 15 inside the housing 10. The roll support unit 23 can removably support the label roll. The roll support unit 23 has a left support unit 24 and a right support unit 25. The left support unit 24 and the right support unit 25 are arranged side by side in the left-right direction inside the storage unit 21, and move left-right in conjunction with each other by a rack-and-pinion mechanism. The left support unit 24 and the right support unit 25 hold the core of the label roll from the left and right sides, respectively, and support the label roll rotatably inside the storage unit 21.

[0017] The cover 12 is an opening / closing member that is pivotally supported around an opening / closing shaft (not shown) that extends in the left-right direction at the upper rear part of the main body part 11. When the cover 12 is closed, the printer 1 has a display part 13 and an operation part 14 on the upper surface of the cover 12. The display part 13 has a liquid crystal display 13A and displays various information. The operation part 14 is used to input various instructions to the printer 1. The cover 12 houses a thermal head 29. The thermal head 29 is provided at the lower front part of the cover 12 and extends in the left-right direction. When the cover 12 is closed, the thermal head 29 faces the platen roller 22. The thermal head 29 has a plurality of heating elements arranged in the left-right direction. The thermal head 29 prints images such as characters and figures on the thermal label 8, which is the printing medium, by selectively heating the heating elements.

[0018] The printer 1 has a mounting section 11A on the front of the main body 11. The mounting section 11A is a section where an optional unit can be mounted to the printer 1. The mounting section 11A is recessed backward, and the platen roller 22 is exposed at the top of the recess. A plurality of guide ribs 11B are formed on the wall surface on the rear side of the recess, protruding obliquely upward and forward, extending from the upper rear to the lower front, and aligned in the left-right direction. The guide ribs 11B extend obliquely downward and forward from the lower part of the platen roller 22. The guide ribs 11B define a transport path T1 (see FIG. 4) of the mount 9 after the thermal label 8 is peeled off after printing, and guide the mount 9 toward a guide rib 31D of the peeler unit 30 described later.

[0019] The optional unit is, for example, a cutter unit that cuts the printed label, a peeler unit 30 that peels the printed label from the mount 9, etc. As shown in Figs. 3 and 4, the printer 1 of this embodiment has the peeler unit 30 attached to the attachment section 11A. The peeler unit 30 is a substantially rectangular box-like shape, and has a frame section 31 and a main body section 32. The frame section 31 is a section that is assembled to the attachment section 11A to fix the peeler unit 30 to the front surface of the main body section 11. The frame section 31 has a pair of vertical frame sections 31A, a horizontal frame section 31B, and a bridging plate 31C. The pair of vertical frame sections 31A are support sections that extend in the up-down direction at both ends in the left-right direction. The vertical frame section 31A has a support section (not shown) at the front lower section that rotatably supports the main body section 32.

[0020] The horizontal frame portion 31B is a bridging portion that extends in the left-right direction and has both ends connected to the rear lower portion of the pair of vertical frame portions 31A. A plurality of guide ribs 31D are formed on the front surface of the horizontal frame portion 31B, which protrude obliquely upward and forward, extend from the upper rear portion to the lower front portion, and are aligned in the left-right direction. The guide ribs 31D are connected to the guide ribs 11B of the mounting portion 11A and extend obliquely downward and forward. The guide ribs 31D define a transport path T2 for the mount 9 between the guide ribs 35 of the main body portion 32, and guide the mount 9 to the lower portion of the peeler unit 30 and discharge it to the outside. The transport path T1 is connected to the transport path T2. The bridging plate 31C is a plate-like member that extends in the left-right direction, and both ends are connected to the upper ends of the pair of vertical frame portions 31A with the thickness direction facing up and down. The lower surface of the bridging plate 31C defines a transport path T3 for the thermal label 8 peeled off from the mount 9 after printing.

[0021] The main body 32 is disposed inside the frame 31 and includes an opening / closing lever 33, a peeling roller 34, guide ribs 35, 36, and a sensor unit 40. The lower end of the main body 32 is rotatably supported by the support of the vertical frame 31A. The main body 32 can be moved between an open state in which the upper portion is tilted forward to expose the platen roller 22, and a closed state in which the upper portion is moved rearward to bring the peeling roller 34 into contact with the platen roller 22. The opening / closing lever 33 is provided on the front wall 32A of the main body 32 and releases a lock mechanism (not shown) that maintains the closed state, allowing the main body 32 to be moved to the open state. The peeling roller 34 is a cylindrical roller for peeling the thermal label 8 from the backing paper 9, and is disposed on the upper end of the rear wall 32B of the main body 32 and extends in the left-right direction. The peeling roller 34 is biased diagonally upward and rearward, and when the main body 32 is in the closed state, it abuts against the platen roller 22 from the lower diagonal front.

[0022] The guide rib 35 is formed on the rear wall 32B of the main body 32, protrudes diagonally downward and rearward, and is a rib-like shape extending from the upper rear part of the rear wall 32B to the lower front part. A plurality of guide ribs 35 are provided and aligned in the left-right direction. The guide rib 35 defines a conveying path T2 for the mount 9 between the guide rib 31D of the frame 31 and the guide rib 31D. The guide rib 36 is formed on the upper wall 32C of the main body 32, protrudes upward, and is a rib-like shape extending from the rear part of the upper wall 32C to the front part. A plurality of guide ribs 36 are provided and aligned in the left-right direction. The upper surface of the upper wall 32C has a plurality of planes aligned in the front-rear direction, and the planes on the front side are inclined downward. The guide rib 36 defines a conveying path T4 along which the thermal label 8 peeled off from the mount 9 is discharged to the outside of the peeler unit 30. The conveying path T3 is connected to the conveying path T4. The guide rib 36 is inclined downward toward the front side in accordance with the shape of the upper wall 32C. The rear part of the guide rib 36 defines a transport path T3 for the heat-sensitive label 8 between the guide rib 36 and the bridging plate 31C of the frame 31, and the front to middle part of the guide rib 36 defines a transport path T4 and also functions as a portion for temporarily placing the discharged heat-sensitive label 8 before the user takes it out. The guide rib 36 forms a gap between the heat-sensitive label 8 and the upper wall 32C so that the adhesive applied to the adhesive surface of the heat-sensitive label 8 does not adhere to the upper wall 32C.

[0023] An opening 37 is provided in the center of the upper wall 32C in the left-right direction. The opening 37 is formed between two guide ribs 36 arranged side by side in the center. A detection portion 47 of the sensor unit 40 is disposed in the opening 37.

[0024] As shown in Figs. 5 to 7, the sensor unit 40 is a sensor for detecting whether or not the thermal label 8 is placed on the guide rib 36. The sensor unit 40 includes an optical sensor 41, a sensor board 42, a metal holder 43, and a holder 45. The optical sensor 41 is a reflective sensor including a light-emitting section 41A and a light-receiving section 41B. The thermal label 8 is printed and peeled off from the backing paper 9, and then placed on the guide rib 36 formed on the upper wall 32C of the main body 32. The optical sensor 41 detects the presence or absence of the thermal label 8 by receiving the reflected light Y reflected by the thermal label 8 by the light-receiving section 41B after the detection light X is emitted from the light-emitting section 41A along the optical path L. The light-emitting section 41A and the light-receiving section 41B are arranged side by side in the left-right direction. As will be described later, the wavelength of the detection light X emitted from the light-emitting section 41A is in the range of 900 nm to 1000 nm. The optical path direction along the optical path L of the detection light X emitted from the light emitting unit 41A is a direction diagonally upward and slightly to the right, and is a direction approximately perpendicular to the horizontal direction of the surface of the transparent portion 47C of the holder 45 that is arranged directly above the optical sensor 41.

[0025] As shown in Fig. 7(A), the sensor board 42 is a wiring board on which the optical sensor 41 is mounted, and is a plate-like board that is long in the left-right direction. The optical sensor 41 is disposed at a position to the left of the center of the upper surface of the sensor board 42. A land for soldering signal lines connected to the light-emitting unit 41A and the light-receiving unit 41B is formed at a position to the right of the center of the upper surface of the sensor board 42. The holding metal fitting 43 is a corrugated, plate-like fitting that is fixed to the upper surface of the sensor board 42 and holds the optical sensor 41 in the central opening. The holding metal fitting 43 protects the optical sensor 41 from impacts caused by, for example, the peeler unit 30 being dropped.

[0026] As shown in FIG. 7B, the holder 45 is a frame that supports the sensor board 42 and extends in the left-right direction. The holder 45 is a part that is molded integrally with a mold using, for example, acrylic resin, and has characteristics for wavelengths that can transmit light, as described later. The holder 45 has a support section 46 and a detection section 47. The support section 46 is a plate-like member that extends in the left-right direction and has a thickness direction that is the up-down direction, and has a recess 48 that opens on the upper surface side and is recessed downward. The recess 48 is formed over almost the entire upper surface of the support section 46, and the sensor board 42 on which the optical sensor 41 is mounted is placed in the recess 48. The bottom wall of the recess 48 opens in the up-down direction, leaving the left and right ends.

[0027] The recess 48 has four support protrusions 51-54, three pressing protrusions 55-57, and two positioning protrusions 58, 59. The support protrusions 51-54 are provided on the bottom wall remaining at the left and right ends of the recess 48, and support the four corners of the lower surface of the sensor board 42 from below. The height position of the support protrusions 51, 53 is higher than the height position of the support protrusions 52, 54. This allows the upper surface of the sensor board 42 to face obliquely upward and forward within the recess 48, and the optical path direction of the detection light X of the optical sensor 41 to be directed obliquely upward and forward.

[0028] The pressing protrusions 55, 56 are provided on the upper ends of the front and rear side walls to the right of the center in the left-right direction of the recess 48, and each protrudes into the recess 48. The pressing protrusion 57 is provided on the upper end of the front side wall to the left of the center in the left-right direction of the recess 48, and protrudes into the recess 48. The pressing protrusions 55-57 press the sensor board 42 from above at two locations on the front edge and one location on the rear edge, and together with the support protrusions 51-54, position the sensor board 42 in the up-down direction. The positioning protrusions 58, 59 are formed on the right side wall of the recess 48, separated from each other in the front-to-rear direction, and each protrudes to the left. The positioning protrusions 58, 59 abut against the right end of the sensor board 42, and position the sensor board 42 in the left-to-right direction within the recess 48.

[0029] A dowel 49A is provided at the left end of the support 46 for attaching the sensor unit 40 to the upper part of the main body 32. A groove 49B is provided at the right end of the support 46 for arranging a signal line drawn from the sensor board 42.

[0030] As shown in FIG. 6 and FIG. 7, the detection unit 47 bridges the upper end of the front side wall of the recess 48 and the upper end of the rear side wall in an arch shape that bulges upward at a position to the left of the approximate center of the left and right of the support unit 46. The position of the detection unit 47 in the left and right direction is a position that covers the entire optical sensor 41 in the up and down direction when the sensor board 42 is placed in the recess 48 of the support unit 46. The detection unit 47 has an upper wall portion 47A and a rear wall portion 47B. When the sensor unit 40 is assembled to the main body portion 32 and the detection unit 47 is placed in the opening 37 of the upper wall 32C, the upper wall portion 47A is placed at a height position approximately the same as the upper surface of the upper wall 32C. The upper surface of the upper wall portion 47A has a shape in which multiple planes are arranged in the front-rear direction and the planes on the front side are inclined downward, similar to the upper surface of the upper wall 32C. The front end of the upper wall portion 47A is connected to the upper end of the front side wall of the support unit 46. A transmissive portion 47C formed in a flat plate shape extending in the left-right direction is provided at the approximate center in the front-rear direction of the upper wall portion 47A. The transmissive portion 47C is located directly above the optical sensor 41 on the sensor substrate 42 supported by the support portion 46. As described above, the holder 45 is an integral part made of acrylic resin, and transmits the detection light X. The sensor substrate 42 is supported in the recess 48 of the support portion 46 so that the optical path direction of the detection light X from the light emitting portion 41A of the optical sensor 41 is perpendicular to both the lower surface 47D, which is a flat surface facing the optical sensor 41 side of the transmissive portion 47C, and the upper surface 47E, which is a flat surface facing the opposite side to the optical sensor 41. As a result, the detection light X enters the transmissive portion 47C along the optical path direction perpendicular to the lower surface 47D of the transmissive portion 47C, exits the transmissive portion 47C along the optical path direction perpendicular to the upper surface 47E, and reaches the thermal label 8, thereby suppressing scattering of the detection light X. The reflected light Y reflected by the thermal label 8 also enters the transmitting portion 47C along an optical path direction perpendicular to the upper surface 47E of the transmitting portion 47C, exits the transmitting portion 47C along an optical path direction parallel to the lower surface 47D, and is received by the light receiving portion 41B, thereby suppressing scattering of the reflected light Y.

[0031] The rear wall portion 47B extends obliquely upward and forward from the upper end of the rear side wall of the support portion 46, and is connected to the rear end of the upper wall portion 47A. By bridging the upper wall portion 47A and the rear wall portion 47B in an arch shape, when the sensor board 42 is placed in the recessed portion 48 of the support portion 46, a gap is formed between the upper surface of the sensor board 42 and the sensor board 42, and the optical sensor 41 can be placed directly below the transmission portion 47C.

[0032] As shown in FIGS. 5 to 7, when assembling the sensor unit 40, the worker inserts the right end of the sensor board 42 into the recess 48 from the left end side of the recess 48, and places both left and right edges of the sensor board 42 on the support protrusions 53, 54. With both left and right edges supported by the support protrusions 53, 54, the worker slides the sensor board 42 and moves the right end below the opening of the bottom wall. When the left end slides near the support protrusions 53, 54, the worker rotates the right end upward with the support protrusions 53, 54 as a fulcrum to return the sensor board 42 into the recess 48, and places both right corners on the support protrusions 51, 52. The worker slides the sensor board 42 to the right while placing the lower surface on the support protrusions 51 to 54. The right end of the sensor board 42 abuts against the positioning protrusions 58, 59, so that the sensor board 42 is positioned in the recess 48 and supported by the holder 45. The optical sensor 41 is disposed in the detection section 47, and is located directly below the transmission section 47C.

[0033] As shown in FIG. 3, when the peeler unit 30 is attached to the attachment section 11A of the printer 1 as an optional unit, the detection section 47 of the sensor unit 40 is exposed to the outside of the printer 1. The light receiving section 41B of the optical sensor 41 detects the reflected light Y based on the intensity regardless of the wavelength of the light, so it is affected by disturbance light. As shown in FIG. 8, the visible light in sunlight is light with a wavelength range of approximately 400 nm to 700 nm, although there are individual differences. The energy of visible light on the earth's surface tends to be high, exceeding the median of the maximum energy of sunlight observed outside the atmosphere. Therefore, if the optical sensor 41 can mainly reduce the influence of visible light, it will be effective as a countermeasure against disturbance light.

[0034] As described above, the holder 45 of the sensor unit 40 is made of acrylic resin and has characteristics for wavelengths through which light can be transmitted. Therefore, by producing the holder 45 using acrylic resin that transmits the detection light X emitted from the light emitting portion 41A of the optical sensor 41 and reduces the transmission of disturbance light, the detection light X can be transmitted in the transmission portion 47C and the transmission of disturbance light can be suppressed. As shown in FIG. 9, the detection light X is light with a relatively high output in the wavelength range of about 900 nm to 1000 nm. Therefore, the holder 45 of this embodiment is produced using acrylic resin that has a filter function that suppresses the transmission of light with a wavelength of less than 900 nm that enters the transmission portion 47C along the optical path direction and transmits light with a wavelength of 900 nm or more. As shown in FIG. 10, the acrylic resin that is the material of the holder 45 of this embodiment has a characteristic that it can transmit about 90% of light with a wavelength of 900 nm or more, and the transmittance of light with a wavelength of less than 900 nm and 700 nm or more decreases as the wavelength becomes smaller, and it is almost not transmitted at less than 700 nm. The transmitting portion 47C of the holder 45 molded from such an acrylic resin has a lower transmittance for light with a wavelength of less than 900 nm in the optical path direction than for light with a wavelength of 900 nm or more.

[0035] In this way, by producing the sensor unit 40 using the holder 45 molded from an acrylic resin having a filtering function, the sensor board 42 on which the optical sensor 41 is mounted can be directly assembled to the holder 45 which is integral with the transmitting portion 47C. Therefore, since no other parts are interposed between the optical sensor 41 and the transmitting portion 47C, it is possible to suppress variation in the distance between the optical sensor 41 and the transmitting portion 47C.

[0036] The operation of the printer 1 during printing will be described. The user opens the cover 12 of the printer 1 and supports the label roll on the roll support section 23 of the storage section 21. The user pulls out the label sheet 7 and places the end above the platen roller 22. The user opens the main body section 32 of the peeler unit 30, peels off a part of the thermal label 8 closest to the end from the backing paper 9, and closes the main body section 32. At this time, the user places the end of the peeled thermal label 8 on the guide rib 36 of the upper wall 32C of the main body section 32, and sandwiches the backing paper 9 between the peeling roller 34 and the platen roller 22. The user closes the cover 12 of the printer 1 and operates the operation section 14 to instruct printing on the thermal label 8.

[0037] The control unit (not shown) of the printer 1 drives the platen roller 22 to transport the backing paper 9 sandwiched between the platen roller 22 and the peeling roller 34 toward the lower part of the peeler unit 30. By transporting the backing paper 9, the label sheet 7 is pulled out from the label roll. The control unit drives the thermal head 29 to print on the thermal label 8. The backing paper 9 passes between the thermal head 29 at the upper part of the platen roller 22, and is transported along an S-shaped transport path that passes between the platen roller 22 and the peeling roller 34 at the lower part and faces downward. The backing paper 9 is pulled as it is transported, so that the downstream end of the thermal label 8 is peeled off from the backing paper 9 at a position between the thermal head 29 and the peeling roller 34 and rides on the upper wall 32C of the main body 32. As the backing paper 9 is transported, the thermal label 8 is guided forward by the guide rib 36 of the upper wall 32C while being peeled off from the backing paper 9.

[0038] When printing is completed, the thermal label 8 is placed on the guide rib 36 and positioned above the detection unit 47. The control unit detects the presence or absence of the thermal label 8 by the optical sensor 41. The optical sensor 41 can suppress the influence of ambient light by the filter function of the holder 45, so that erroneous detection of the presence or absence of the thermal label 8 can be suppressed. The control unit waits while the optical sensor 41 detects the thermal label 8. When the user picks up the printed thermal label 8 and the optical sensor 41 no longer detects the thermal label 8, the control unit conveys the label sheet 7 and prints on the next thermal label 8. The newly printed thermal label 8 is peeled off from the backing 9 and placed on the guide rib 36. The control unit waits without performing the next printing while the optical sensor 41 detects the thermal label 8.

[0039] As described above, a part of the light with a wavelength of less than 900 nm directed toward the light receiving section 41B of the optical sensor 41 is blocked by the transmitting section 47C of the holder 45, so that the amount of disturbance light, such as sunlight, received by the light receiving section 41B is reduced. Therefore, the printer 1 can prevent erroneous detection of the thermal label 8.

[0040] The lower surface 47D and the upper surface 47E of the transmitting portion 47C through which the detection light X passes along the optical path L are flat. In this case, scattering of the sensor light when passing through the transmitting portion 47C is suppressed. Therefore, the printer 1 can further suppress erroneous detection of the thermal label 8.

[0041] A guide rib 36 is formed on the upper wall 32C of the main body 32 of the peeler unit 30. In this case, the guide rib 36 keeps the thermal label 8 away from the upper surface of the upper wall 32C and the upper surface 47E of the transparent portion 47C, preventing the thermal label 8 from contacting the transparent portion 47C. Therefore, the printer 1 can prevent the transparent portion 47C from becoming dirty or damaged.

[0042] The optical sensor 41 is a reflective sensor that integrally includes a light emitting portion 41A and a light receiving portion 41B. In this case, the printer 1 supports the light emitting portion 41A and the light receiving portion 41B with a single holder 45. This allows the printer 1 to be made compact.

[0043] The holder 45 is integrally formed with the support portion 46 and the detection portion 47 having the transmission portion 47C. In this case, the printer 1 can suppress variation in the distance between the transmission portion 47C and the optical sensor 41 in the light path direction.

[0044] In the above embodiment, the thermal label 8 is an example of the "medium" of the present invention. The transport path T4 is an example of the "transport path" of the present invention. The upper wall 32C is an example of the "regulating member" of the present invention. The detection light X is an example of the "sensor light" of the present invention. The transmission portion 47C is an example of the "filter plate" of the present invention. The lower surface 47D and the upper surface 47E are examples of the "area" of the present invention. The opening 37 is an example of the "opening" of the present invention. The upper surface of the upper wall 32C is an example of the "extension plate" of the present invention. The guide rib 36 is an example of the "protrusion" of the present invention. The thermal head 29 is an example of the "printing unit" of the present invention. The peeler unit 30 is an example of the "attachment unit" of the present invention.

[0045] The present invention can be modified from the above embodiment. The optical sensor 41 is not limited to a reflective type but may be a transmissive type, and the light emitting section 41A may be provided at a position facing the light receiving section 41B across the transport path T4. The holder 45 is not limited to one in which the support section 46 and the detection section 47 are integrally molded, but may be molded separately. In this case, the detection section 47 including the transmission section 47C needs to be molded using acrylic resin, but the support section 46 may be made of other materials. The holder 45 is not limited to acrylic resin, and may be molded using glass material or the like as long as it has a filter function.

[0046] The characteristic of the filter function of the acrylic resin shown in FIG. 10 is merely an example, and it is sufficient to obtain a characteristic that can have a sufficient difference in transmittance with respect to the wavelength of light of 900 nm as a reference. For example, in the characteristic of the filter function of the acrylic resin shown in FIG. 10, the transmittance changes from 0% to 87% in the range of the wavelength of light of 700 nm to 800 nm, and the transmittance reaches 90% after exceeding 820 nm. In contrast, the holder 45 may be molded using an acrylic resin having a characteristic in which the wavelength range in which the transmittance changes significantly is shifted to the longer side by 100 nm. In this case, even if the transmittance at 900 nm is 87%, the transmittance of light with a wavelength of less than 900 nm is clearly lower than the transmittance of light with a wavelength of 900 nm or more, so that the holder 45 can have a filter function that sufficiently suppresses the influence of disturbance light. [Explanation of symbols]

[0047] 1. Printer 8 Thermal Labels 10. Chassis 29 Thermal Head 30 Pila Unit 32C upper wall 36 Guide rib 37 Opening 41 Optical Sensor 41A Light emitting part 41B Light receiving section 45 Holder 46 Support part 47C Transparent part 47D Bottom 47E Top L optical path T4 Transport Path X-detection light

Claims

1. A printer that prints on a medium, A defining member that defines a transport path of the medium; a light emitting unit facing the transport path and emitting sensor light having a wavelength of 900 nm or more; an optical sensor facing the transport path and including a light receiving unit receiving the sensor light emitted by the light emitting unit, the optical sensor detecting the medium on the transport path; a holder including a support portion for supporting the optical sensor and a filter plate disposed on an optical path of the sensor light emitted by the light emitting portion and extending so as to intersect with the optical path; Equipped with In the optical path direction along the optical path, the transmittance of the filter plate for light having a wavelength of less than 900 nm is lower than the transmittance of the filter plate for light having a wavelength of 900 nm or more. A printer characterized by:

2. The area of ​​the filter plate on both sides in the optical path direction through which the sensor light passes is a flat surface.

2. The printer according to claim 1,

3. The defining member is an extension plate extending in a direction intersecting the optical path direction and having an opening; a protrusion that protrudes from the extension plate toward the transport path in the optical path direction and supports the medium on the transport path; having the holder is fixed to the defining member with the filter plate disposed in the opening, a surface of the filter plate facing the transport path is located in a direction from the tip of the protrusion to the extension plate in the optical path direction, the surface being closer to the tip of the protrusion than the tip of the protrusion; 2. The printer according to claim 1,

4. The optical sensor is a reflective sensor including the light emitting portion and the light receiving portion.

2. The printer according to claim 1,

5. The holder is integrally formed by the support portion and the filter plate.

2. The printer according to claim 1,

6. In a printer having a housing that houses a printing unit that prints on a medium, a mounting unit is mounted on a surface of the housing that has an outlet through which the medium printed by the printing unit is discharged, a defining member that defines a transport path of the medium discharged from the discharge port; a light emitting unit facing the transport path and emitting sensor light having a wavelength of 900 nm or more; an optical sensor facing the transport path and including a light receiving unit receiving the sensor light emitted by the light emitting unit, the optical sensor detecting the medium on the transport path; a holder including a support portion for supporting the optical sensor and a filter plate disposed on an optical path of the sensor light emitted by the light emitting portion and extending so as to intersect with the optical path; Equipped with In the optical path direction along the optical path, the transmittance of the filter plate for light having a wavelength of less than 900 nm is lower than the transmittance of the filter plate for light having a wavelength of 900 nm or more. A mounting unit characterized by:

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