Printer

Abstract

A printer according to one embodiment of the present invention is provided with: a transport roller that transports a continuous body and an ink ribbon; a printing head that nips the ink ribbon and the continuous body together with the conveyance roller at a printing position and prints information on each printing medium of the continuous body; and a first detection unit that is provided on the upstream side of the continuous body in the conveyance direction with respect to the printing position, and detects an end portion of each printing medium in the conveyance direction of the continuous body. The first detection unit has a light-emitting element and a light-receiving element that receives light from the light-emitting element via the ink ribbon and the continuous body.

Description

Technical Field

[0001] The present invention relates to printers. Background Art

[0002] Conventionally, there is a known printer that feeds continuous paper having printing media such as labels attached to a strip of backing paper at intervals and in a removable manner. A sensor is provided in the printer to detect the printing medium when information such as text, symbols, graphics, or barcodes is printed on the printing medium.

[0003] For example, Japanese Patent Publication No. 2019-73025 describes a printer having a sensor for detecting the position of continuous paper conveyed to the upper surface of a paper guide, and realizing printing timing based on the information detected by the sensor, thereby printing desired information on a label of the continuous paper.

[0004] However, in conventional printers, the sensor for detecting the print medium is located upstream of the thermal head that prints on the transport path of the print medium and is relatively far from the thermal head. Figure 10 ) described in the printer, the sensor unit, including the sensor, is located upstream of the platen roller, which holds the label together with the thermal head during printing, and at a relatively long distance from the platen roller. Consequently, the accuracy of the print start position relative to the print medium based on the sensor's detection results may be insufficient. The following reasons are cited as reasons for this.

[0005] The diameter of a printer's platen roller expands and contracts with temperature fluctuations and also shrinks due to wear. Furthermore, when transporting print media, the heavy transport load applied to large rolls of paper can cause the print media to slip. This is particularly true at the start of transport, where the print media is held between the thermal head and the platen roller. Therefore, even if the platen roller rotational distance for transporting continuous paper from the sensor detection position to the print start position is pre-set based on the physical distance, there is still a possibility of slight deviation from the print start position. Furthermore, when the transport path between the sensor detection position and the print start position is long, the set platen roller rotational distance increases. Consequently, fluctuations in the platen roller diameter and the cumulative effects of slippage can lead to unignorable deviations from the print start position. In particular, when the transport length of a single label (print media) is short and there are multiple labels between the sensor detection position and the thermal head, the platen roller may repeatedly rotate forward and backward, increasing the actual transport distance and making the deviation from the print start position more noticeable. Summary of the Invention

[0006] Therefore, an object of the present invention is to improve the accuracy of the printing start position for each print medium when printing information on each print medium in a continuous body including a strip-shaped backing paper and a plurality of print media attached to the backing paper in a removable manner with spaced intervals.

[0007] One embodiment of the present invention is a printer comprising:

[0008] a conveying roller that conveys a continuous body and an ink ribbon, wherein the continuous body includes a strip-shaped backing paper and a plurality of printing media attached to the backing paper at intervals and in a releasable manner;

[0009] a print head that, at a printing position, clamps the ink ribbon and the continuous body together with the transport roller and prints information on each printing medium of the continuous body; and

[0010] The first detection unit is arranged on the upstream side of the conveying direction of the above-mentioned continuum relative to the above-mentioned printing position, has a light-emitting element and a light-receiving element that receives light from the above-mentioned light-emitting element via the above-mentioned ink ribbon and the above-mentioned continuum, and detects the end of each printing medium in the conveying direction of the above-mentioned continuum.

[0011] According to one aspect of the present invention, when information is printed on each continuous print medium including a tape-shaped backing paper and a plurality of print media attached to the backing paper at intervals and in a removable manner, the accuracy of the printing start position for each print medium can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a perspective view of a printer according to one embodiment.

[0013] Figure 2 This is a perspective view of a printer according to one embodiment, showing the interior thereof visible, together with the structure of continuous paper.

[0014] Figure 3 This is a side view of a printer according to one embodiment, showing the interior of the printer.

[0015] Figure 4 This is a perspective view of a printing section of a printer according to one embodiment when the print head unit is in an open state.

[0016] Figure 5 This is a perspective view of a label support mechanism of a printer according to one embodiment.

[0017] Figure 6 This is a partial cross-sectional view of a label support mechanism of a printer according to one embodiment.

[0018] Figure 7This is a perspective view of a portion of a head mechanism unit of a printer according to one embodiment, as viewed from above.

[0019] Figure 8 This is a perspective view of a portion of a head mechanism unit of a printer according to one embodiment, as viewed from below.

[0020] Figure 9 Contains an exploded perspective view of the head assembly mounted on the head mechanism and a cross-sectional view of the thermal head.

[0021] Figure 10 yes Figure 7 A partial exploded perspective view of the head mechanism.

[0022] Figure 11 These are diagrams explaining a method for assembling a sensor assembly to a head cover in a printer according to one embodiment.

[0023] Figure 12 These are diagrams explaining a method for assembling a sensor assembly to a head cover in a printer according to one embodiment.

[0024] Figure 13 The diagram includes a partial top view of a head cover in a printer according to one embodiment and an enlarged partial cross-sectional view of the head cover after the sensor assembly is assembled therein.

[0025] Figure 14 It means from Figure 8 A diagram showing the head mechanism with the head cover removed.

[0026] Figure 15 This is a partial cross-sectional view of a printer according to one embodiment.

[0027] Figure 16 It will Figure 15 An enlarged view of the portion related to the light-transmitting sensor in FIG.

[0028] Figure 17 This is a diagram illustrating a head position adjustment function in a printer according to one embodiment.

[0029] Figure 18 This is a partial cross-sectional view showing the positional relationship of the periphery of the light transmission sensor before and after head position adjustment in a printer according to one embodiment. DETAILED DESCRIPTION

[0030] The aspects described below are not limited to the drawings explained through the simple description of the drawings.

[0031] In the following description, the so-called "conveying path" does not refer to a specific component in the printer, but refers to the passage through which the continuous paper or ink ribbon passes when being transported in the printer (in other words, the space through which the continuous paper or ink ribbon can pass in the printer).

[0032] A first aspect of certain aspects of the present invention is a printer comprising:

[0033] a conveying roller that conveys a continuous body and an ink ribbon, wherein the continuous body includes a strip-shaped backing paper and a plurality of printing media attached to the backing paper at intervals and in a releasable manner;

[0034] a print head that, at a printing position, clamps the ink ribbon and the continuous body together with the transport roller and prints information on each printing medium of the continuous body; and

[0035] The first detection unit is arranged on the upstream side of the conveying direction of the above-mentioned continuum relative to the above-mentioned printing position, has a light-emitting element and a light-receiving element that receives light from the above-mentioned light-emitting element via the above-mentioned ink ribbon and the above-mentioned continuum, and detects the end of each printing medium in the conveying direction of the above-mentioned continuum.

[0036] According to the first aspect of one embodiment of the present invention, the light emitting element and the light receiving element of the first detection unit can be arranged close to the printing position, thereby improving the accuracy of the printing start position for each print medium.

[0037] A second aspect of one aspect of the present invention is based on the printer described in the first aspect, wherein:

[0038] The printer includes a medium support portion having a support surface for supporting the continuous body toward the transport roller from a backing paper side.

[0039] The light emitting element is arranged on a side where the print head is provided with respect to a conveying path of the ink ribbon toward the conveying roller.

[0040] The light receiving element receives light at the supporting surface.

[0041] According to the second aspect of one embodiment of the present invention, the light emitting element and the light receiving element of the first detection unit can be arranged at positions close to the printing position.

[0042] A third aspect of one aspect of the present invention is based on the printer described in the first or second aspect, wherein:

[0043] The print head has a substrate provided with a heating portion.

[0044] The light emitting element is arranged directly below the substrate.

[0045] According to the third aspect of one embodiment of the present invention, the light emitting element can be arranged near the printing position.

[0046] A fourth aspect of one aspect of the present invention is a printer according to any one of the first to third aspects, wherein:

[0047] The print head has a heat dissipation portion.

[0048] The light emitting element is disposed between the heat dissipation portion and the ink ribbon.

[0049] According to the fourth aspect of one embodiment of the present invention, the light emitting element of the first detection unit can be arranged at a position close to the printing position.

[0050] A fifth aspect of one aspect of the present invention is a printer according to any one of the first to fourth aspects, wherein:

[0051] When the printer is viewed from the side, the direction from the position of the light emitting element toward the position of the light receiving element is directed toward the side where the printing position is set, based on a virtual perpendicular line drawn from the position of the light emitting element to the installation surface where the printer is set.

[0052] According to the fifth aspect of one embodiment of the present invention, the light emitting element of the first detection unit can be arranged at a position close to the printing position.

[0053] A sixth aspect of one aspect of the present invention is a printer according to any one of the first to fifth aspects, wherein:

[0054] When the printer is viewed from the side, the print head becomes thinner as it moves in a direction opposite to the conveying direction of the ink ribbon, thereby forming a space between the print head and the ink ribbon.

[0055] The light emitting element is disposed in the space.

[0056] According to the sixth aspect of one embodiment of the present invention, the light emitting element of the first detection unit can be arranged at a position close to the printing position.

[0057] A seventh aspect of one aspect of the present invention is a printer according to any one of the first to sixth aspects, wherein:

[0058] The printer is configured such that a conveyance path for the ink ribbon and a conveyance path for the continuous body are directed toward an installation surface on which the printer is installed as they move upstream from the printing position.

[0059] According to the seventh aspect of one embodiment of the present invention, the light emitting element can be provided in a position particularly close to the heating element of the print head in the space immediately below the substrate of the print head.

[0060] An eighth aspect of a certain aspect of the present invention is based on the printer described in the third aspect, wherein:

[0061] The printer includes a head cover disposed between the substrate and the ink ribbon conveyance path.

[0062] The light emitting element is housed in the head cover.

[0063] According to the eighth aspect of one embodiment of the present invention, there is an advantage in space efficiency when arranging the light emitting element near the print head.

[0064] A ninth aspect of a certain aspect of the present invention is based on the printer described in the eighth aspect, wherein:

[0065] The head cover is formed with a through hole for allowing the light emitted by the light emitting element to pass therethrough.

[0066] According to the ninth aspect of one embodiment of the present invention, the light emitting element can be housed in the head cover and emit light toward the light receiving element.

[0067] A tenth aspect of one aspect of the present invention is a printer according to any one of the first to ninth aspects, wherein:

[0068] A guide portion is provided on the upstream side of the light receiving element in the conveyance direction, the guide portion guiding the continuous body toward the conveyance roller from the printing medium side.

[0069] According to the tenth aspect of one embodiment of the present invention, since the guide portion supports the continuous body, the amount of movement of the continuous body in the direction perpendicular to the backing paper is restricted, thereby further improving the detection accuracy of the first detection portion.

[0070] An eleventh aspect of one aspect of the present invention is a printer according to any one of the first to tenth aspects, wherein:

[0071] The printer includes a second detection unit, which is provided upstream of the first detection unit in the conveyance direction of the continuous body and detects an end portion of each printing medium in the conveyance direction of the continuous body.

[0072] The second detection unit includes a light emitting element and a light receiving element, and the element located farther from the installation surface of the printer is arranged between the conveyance path of the ink ribbon and the conveyance path of the continuous body.

[0073] According to the eleventh aspect of one embodiment of the present invention, since two detection units are provided at different positions in the conveyance direction, any detection unit can be flexibly applied according to the accuracy requirement of the printing start position for each print medium.

[0074] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings.

[0075] Figure 1 1 shows the appearance of a printer 1 according to one embodiment. Figure 1 As shown in FIG, XYZ coordinates are defined. Specifically, +X and −X represent the left and right directions of the printer 1, +Y and −Y represent the front and back directions of the printer 1, and +Z and −Z represent the top and bottom directions of the printer 1.

[0076] The printer 1 has an issuing port 5 for issuing (discharging) printed labels on its front surface. An opening cover 6 is attached to one side of the printer 1 so as to be vertically openable and closable by two hinges 7 .

[0077] Figure 2 and Figure 3 These are a perspective view and a side view of the main part of the printer 1 with the interior visible.

[0078] Inside the printer 1 , there are provided a paper supply unit 10 disposed at the rear, a printing unit 11 disposed at the front, and an ink ribbon unit 12 disposed at the top.

[0079] The paper supply unit 10 is loaded with roll paper R. Figure 2 As shown, the paper roll R is made of continuous paper CP wound into a roll shape. The continuous paper CP includes a strip-shaped backing paper PM and a plurality of labels PL installed on the backing paper PM in a spaced and removable manner. The surface (surface) of the backing paper PM that contacts the adhesive surface of the label PL is coated with a release agent such as silicone, thereby making it easy to peel off the label PL. In addition, position detection marks IM indicating the position of the label can be formed at predetermined intervals along the long side direction on the surface (back side) of the backing paper PM to which the label PL is not adhered. For the label PL, there are cases where thermal paper is used and cases where ordinary paper is used. When thermal paper is used, a thermosensitive color-developing layer is formed on the surface of the thermal paper, which develops a specific color (black, red, etc.) when a predetermined temperature range is reached. Although not shown in the figure, a roll of paper in which a linerless label is wound into a roll can also be loaded into the paper supply unit 10, and the linerless label has an adhesive surface coated with an adhesive formed on the back side of the printing surface.

[0080] The paper supply unit 10 includes a support shaft 10a and a roll paper guide 10b. The support shaft 10a holds the roll paper R and supplies the continuous paper CP drawn from the roll paper R to the printing unit 11. The support shaft 10a rotatably supports the roll paper R. The roll paper guide 10b secures the roll paper R and is movable along the axial direction of the support shaft 10a so that its position can be changed according to the width of the roll paper R.

[0081] There are two types of continuous paper CP: front-end wound labels and back-end wound labels. The front-end wound labels are wound in a state where the label PL of the continuous paper CP is located on the outer peripheral surface of the roll paper R. Figure 3 As shown in FIG. 1 , the continuous paper CPs (dashed line) is drawn from the center of the paper supply unit 10 in the height direction toward the bottom of the printing unit 11. In contrast, the back-wound label is wound with the label PL of the continuous paper CP located on the inner circumference of the roll paper R, as shown in FIG. Figure 3 As shown, continuous paper CPb (solid line) is drawn from near the bottom of the printer 1 toward the bottom of the printing unit 11. The paper feed path of continuous paper CP (CPs, CPb) in the printing unit 11 is the same regardless of whether the paper is wound on the front or back. Whether the paper is wound on the front or back, the continuous paper CP is conveyed with the printed surface of the label PL facing upward.

[0082] The printing section 11 includes a print head unit 13 , a support base 14 and a damper 15 arranged below the print head unit 13 . The printing section 11 prints labels PL on continuous paper CP.

[0083] As will be described later, the print head unit 13 is provided in an openable and closable state inside the printer 1. When the print head unit 13 is closed, a paper feed path is formed between the print head unit 13 and the support platform 14. The paper feed path is connected to the issuing port 5 (see Figure 1 ) are connected.

[0084] A head lock lever 16 is provided on the support base 14 to maintain the closed state of the print head unit 13. When the head lock lever 16 is operated, the closed state of the print head unit 13 is released, the front portion of the print head unit 13 is lifted, and the print head unit 13 is opened (separated from the platen roller 23).

[0085] The damper 15 applies tension to the continuous paper CP. In this embodiment, the damper 15 includes an outer damper 15a and an inner damper 15b, and moves up and down (opens and closes) in conjunction with the opening and closing of the print head unit 13. However, when the print head unit 13 is closed, the outer damper 15a and the inner damper 15b are each arranged to swing to apply tension to the continuous paper CP.

[0086] The ink ribbon unit 12 includes a ribbon supply unit 12a and a ribbon take-up unit 12b, which supply and take up an ink ribbon RB coated with printing ink. The ribbon supply unit 12a supports the ink ribbon RB so that the rolled ink ribbon RB can rotate. The ribbon take-up unit 12b takes up and recovers the printed ink ribbon RB. When using the ink ribbon RB, the ink ribbon RB drawn from the ribbon supply unit 12a is passed under the print head unit 13 and taken up by the ribbon take-up unit 12b.

[0087] In this printer 1, continuous paper CP (CPs, CPb) is unwound from a paper roll R located in the paper supply unit 10 and conveyed via a damper 15 to a paper path between the print head unit 13 and the support platform 14. During this process, labels PL are printed on the continuous paper CP. After printing, the continuous paper CP is discharged from the printer 1 through the issuing port 5.

[0088] Next, refer to Figure 4 The structure of the above-mentioned printing unit 11 will be described.

[0089] Figure 4 This is a perspective view of the printing section 11 with the print head unit 13 in an open state.

[0090] like Figure 4 As shown, the print head unit 13 is supported by a swing shaft S1 provided at the rear thereof on a main frame (not shown) so that the print head unit 13 can swing (ie, open and close) around the X-axis.

[0091] On the lower surface of the print head unit 13 (the surface facing the paper path), a thermal head 18 (an example of a print head) is installed with its heating element 18L facing the paper path. The heating element 18L of the thermal head 18 is composed of a glaze layer that protrudes a predetermined amount (e.g., several tens of micrometers) from the substrate of the thermal head 18. It contains multiple heating resistors (heating elements) that generate heat when energized, thereby printing labels PL on continuous paper CP. These multiple heating resistors are arranged in a row along the width direction of the continuous paper CP (a direction perpendicular to the direction in which the continuous paper CP is transported).

[0092] A pair of engaging claws 19 are provided on the lower surface of the front side of the print head unit 13 so as to sandwich the axis of the thermal head 18 (see FIG. Figure 4 Behind the engaging claws 19 in the print head unit 13, pins 20 are provided that protrude outward from both sides of the print head unit 13.

[0093] Although the print head unit 13 is biased toward opening by a torsion spring (not shown) attached to the swing shaft S1, it remains closed by a pair of locking claws 22 on the support base 14, which are hooked onto a pair of pins 20 at the bottom of the print head unit 13. When the head lock lever 16 is operated rearward, the locking claws 22 move rearward in conjunction with this movement and disengage from the pins 20. When the locking claws 22 disengage from the pins 20, the print head unit 13 automatically opens due to the force of the torsion spring.

[0094] When the print head unit 13 is in the closed state, the pair of engagement claws 19 (see Figure 4 ) is fitted with both end portions of the rotating shaft of the platen roller 23 (an example of a conveying roller).

[0095] The platen roller 23 feeds the continuous paper CP fed from the paper supply unit 10 along the paper feed path to the paper outlet 5 (see FIG. Figure 1 ) transport. The platen roller 23 is mounted on top of the support platform 14 in a rotatable state in both forward and reverse directions. During printing, it rotates while sandwiching the continuous paper CP with the thermal head 18. A gear G1 is connected to one axial end of the rotation shaft of the platen roller 23. This gear G1 engages with the rotation shaft of a stepping motor (not shown).

[0096] When the continuous paper CP is plain paper, the platen roller 23 rotates while holding the continuous paper CP and the ink ribbon RB together with the thermal head 18 during printing. In this case, the ink ribbon RB is fed from the tape supply unit 12a via the tape rollers 121 and 122 (see FIG. 1 ) provided in the print head unit 13. Figure 4 ) for transport and winding on the belt winding portion 12b.

[0097] Next, refer to Figure 5 and Figure 6 The tag supporting mechanism 70 will be described.

[0098] like Figure 4 As shown, the label support mechanism 70 is arranged on the support platform 14 .

[0099] Figure 5 A perspective view of the label support mechanism 70 is shown in each of the guide position for narrow labels and the guide position for wide labels.

[0100] like Figure 5As shown, the label support mechanism 70 includes a label support portion 71, a sensor assembly 72, and a label guide portion 73 (an example of a guide portion). The label support portion 71 (an example of a medium support portion) includes a support surface 711 that supports the continuous paper CP toward the platen roller 23 from the bottom side. In one embodiment, the support surface 711 is formed with a plurality of protrusions in a manner that enables smooth conveyance of linerless labels as continuous paper. The so-called linerless label refers to a label having an adhesive surface coated with an adhesive formed on the side opposite to the printing surface. The plurality of protrusions on the support surface 711 play a role in assisting conveyance by reducing the contact area with the adhesive surface of the linerless label.

[0101] The sensor assembly 72 is mounted on the label support 71 so as to be slidable in the width direction of the continuous paper CP. It incorporates both a transmissive sensor and a reflective sensor. The label guide 73 is mounted on the sensor assembly 72. The continuous paper CP, which is fed toward the platen roller 23, is sandwiched between the label guide 73 and the support surface 711 of the label support 71. The label guide 73 guides the continuous paper CP from above.

[0102] Figure 6 A schematic cross section of the sensor assembly 72 and the tag guide 73 is shown when the tag support mechanism 70 is cut along a plane perpendicular to the surface of the conveyed continuous paper CP and extending in the width direction (X direction) of the continuous paper CP.

[0103] like Figure 6 As shown, the label guide 73 is attached to the sensor assembly 72. A small gap g1 is formed between the lower surface of the label guide 73 and the support surface 711 of the label support 71. This gap g1 serves as a conveyance path for the continuous paper CP.

[0104] The label support portion 71 is provided with a guide protrusion 712 and a guide groove 713 in the longitudinal direction thereof, which engage with the sensor assembly 72. The sensor assembly 72 can slide in the longitudinal direction (i.e., the width direction of the continuous paper CP) while engaging with the guide protrusion 712 and the guide groove 713 of the label support portion 71, depending on the width of the label being used.

[0105] The sensor assembly 72 is a structure in which a swinging portion 721 located at the top and a sliding portion 722 located at the bottom are connected to each other and can swing via a swinging shaft 723. The sliding portion 722 can engage with the guide protrusion 712 and the guide groove 713 of the tag support portion 71 and slide in the longitudinal direction. The swinging portion 721 can swing from the position close to the sliding portion 722 around the swinging shaft 723. Figure 6 The position shown (the position when the printer 1 is in operation) is moved in a direction away from the sliding portion 722 (i.e., Figure 6By swinging in the counterclockwise direction in the figure, new continuous paper CP can be arranged in the printer 1.

[0106] like Figure 6 As shown, in the sensor assembly 72, a light-emitting element 621 is disposed in the swinging portion 721, and a light-receiving element 622 is disposed in the sliding portion 722. The light-emitting element 621 and the light-receiving element 622 are positioned opposite each other, forming the light-transmitting sensor 62. Since the ink ribbon RB feed path is located above the label guide 73, the light-emitting element 621, located above the light-receiving element 622, is positioned between the ink ribbon RB feed path and the continuous paper CP feed path. When the light-receiving element 622 receives light emitted from the light-emitting element 621, the light-transmitting sensor 62 detects the end of each label PL in the continuous paper CP feed direction based on the difference in light intensity between light that has passed through both the label PL and the backing paper PM and light that has passed through only the backing paper PM.

[0107] In addition, Figure 6 In the embodiment, the light emitting element 621 is arranged above the light receiving element 622 (ie, at a distance from the installation surface MS (see FIG. 1 ) on which the printer 1 is installed). Figure 3 The positions of the light emitting element 621 and the light receiving element 622 may be reversed, and the light receiving element 622 may be arranged at a position above the light emitting element 621.

[0108] Furthermore, a reflective sensor 63 is provided on the sliding portion 722. The reflective sensor 63 includes a light emitting element and a light receiving element arranged in parallel. The reflective sensor 63 detects the mark IM at the presence position (see FIG. 1 ) based on the light intensity of the reflected light emitted from the light emitting element and reflected by the back surface of the backing paper PM. Figure 2 ) and the portion where the position detection mark IM is not present, the end portion of each label PL in the conveyance direction of the continuous paper CP is detected.

[0109] Next, refer to Figures 7 to 14 The head mechanism 35 provided in the print head unit 13 will be described. The head mechanism 35 is a mechanism related to the thermal head 18 in a state where the support plate 17, the belt rollers 121 and 122, the swing shaft S1, etc. are removed from the print head unit 13.

[0110] Figure 7 This is a perspective view of the main part of the head mechanism unit 35 as seen from above. Figure 8 This is a perspective view of the main part of the head mechanism unit 35 as seen from below.

[0111] like Figure 7 and Figure 8As shown, the head mechanism section 35 includes the thermal head 18 , a head holding section 36 , a pin pressing section 37 , a head cover 39 , a swing shaft 40 (an example of a shaft section), a rotation shaft 41 , and the like.

[0112] exist Figure 7 and Figure 8 Although not visible in the figure, a head attachment 38 is fixed to the thermal head 18 .

[0113] Figure 9 The present invention includes an exploded perspective view showing how to install the thermal head 18 and the head attachment 38, and a cross-sectional view of the thermal head 18 (a cross-sectional view cut at the center in the longitudinal direction). Figure 9 As shown, the head attachment 38 is a plate-shaped component having a central plate 381 and a pair of end plates 382 extending downward from both ends of the central plate 381. A pin 38P is attached to the upper surface of the central plate 381, projecting upward. The pin 38P has a columnar portion 38Pc extending upward from the surface of the central plate 381, and a tapered portion 38Pt tapering at the upper tip of the columnar portion 38Pc. A recess 38Pr is formed in the columnar portion 38Pc, which is recessed toward the +X side. Although described later, the pin 38P is provided to enable the head holder 36 to hold the thermal head 18.

[0114] The thermal head 18 includes a heat sink 181 (an example of a heat dissipation unit), a substrate 183, and a connector 184. The substrate 183 may be formed by connecting two or more substrates, forming the aforementioned heat generating unit 18L. The heat sink 181 is provided to efficiently dissipate the heat generated by the substrate 183. Two threaded holes 181a are formed in the heat sink 181.

[0115] As shown in the cross-sectional view of the thermal head 18, the substrate 183 includes a first substrate portion 183a on which the heat generating portion 18L is arranged, a second substrate portion 183b connected to the connector 184, and a flexible substrate portion 183c connecting the first and second substrate portions 183a and 183b. The heat sink 181 is designed to be thickest at the first substrate portion 183a of the substrate 183 to efficiently dissipate heat from the first substrate portion 183a, which generates the most heat.

[0116] A protrusion 1811 protruding downward is formed at the front end of the heat sink 181 to cover the front end of the first substrate 183a. This prevents paper jams when continuous paper CP (especially thick paper) is reversely fed.

[0117] like Figure 9As shown, two holes 381a are formed in the center plate 381 of the head attachment 38, and screws 383 are fastened through the holes 381a and threaded holes 181a of the thermal head 18, thereby securing the head attachment 38 to the thermal head 18. In the following description, the component in which the thermal head 18 and the head attachment 38 are integrated will be appropriately referred to as the "head assembly 18A."

[0118] A pair of cutouts 382a are formed at the front ends of the end plates 382 on either side of the head attachment 38. The cutouts 382a have a U-shaped configuration that opens upward. Cutouts 382b are formed at the rear ends of the end plates 382 on either side of the head attachment 38. As will be described later, the cutouts 382a are provided to adjust the front-to-back position of the thermal head 18.

[0119] Next, refer to Figure 10 The structure of the main portion of the head mechanism unit 35 will be described. Figure 10 yes Figure 7 The exploded perspective view of the head mechanism portion 35 is shown. Figure 7 The circuit board 50 shown is fixed to the head cover 39, but Figure 10 In the figure, the hood 39 is not shown for visibility.

[0120] like Figure 10 As shown, the head mechanism 35 is formed by assembling the head holding portion 36, the head assembly 18A and the head cover 39 in order from the top. The head holding portion 36 and the head cover 39 are supported by the swing shaft 40. The swing shaft 40 is provided in parallel with the axis of the platen roller 23. Figure 4 As shown, the swing shaft 40 is supported by the support plate 17 and fixed to an internal frame (not shown) located inside the support plate 17 and formed integrally with the support plate 17 .

[0121] The head holding portion 36 holds the head assembly 18A so that it does not fall due to its own weight, and releases the head assembly 18A from its holding position in response to a predetermined operation of the head holding release portion 30. The head assembly 18A can be easily removed from the head holding portion 36 by operating the head holding release portion 30. Although not shown, the head holding release portion 30 is exposed so that the user can operate it when the print head unit 13 is in the open position.

[0122] The head holding portion 36 includes a plate-shaped member and a pin pressing portion 37. The plate-shaped member includes a support plate 361 and side walls 362 provided on the left and right ends of the support plate 361. The head holding portion 36 removably holds the head assembly 18A. A pair of engaging claws 19 are formed at the front ends of the side walls 362 on either side of the head holding portion 36, which engage with the ends of the rotating shaft of the platen roller 23. Insertion holes 362a and 362b are formed at the rear ends of the side walls 362 on either side of the head holding portion 36, through which the swing shaft 40 is inserted.

[0123] The operating unit 42 is a rotary operating unit used to adjust the position of the thermal head 18 by moving the head assembly 18A forward and backward. The forward and backward direction refers to the forward direction when the labels PL printed by the thermal head 18 are traveling forward. Adjusting the position of the thermal head 18 in the forward and backward direction is performed to achieve optimal print quality based on the type of label (thickness, hardness, etc.).

[0124] The side walls 362 on either side of the support plate 361 of the head holding portion 36 pivotally support a rotating shaft 41 that rotates in response to a rotational operation of the operating portion 42. U-shaped cutouts 382a at either end of the head assembly 18A engage with the ends of the rotating shaft 41 from below, thereby engaging the head assembly 18A with the rotating shaft 41. The rotating shaft 41 and the cutouts 382a of the head assembly 18A that engage with the rotating shaft 41 constitute a position adjustment mechanism. Details of the head position adjustment will be described later.

[0125] The printer 1 may also employ a mechanism for adjusting the pressing force applied by the thermal head 18 to the platen roller 23. For an example of a pressing force adjustment mechanism, please refer to Japanese Patent Application Laid-Open No. 2015-123628 filed by the applicant of the present application.

[0126] The pin pressing portion 37 has a pressing plate 37a and a coil spring 37b. When the head assembly 18A is held by the head holding portion 36, the pin pressing portion 37 presses the pin 38P of the head assembly 18A. The pressing plate 37a is provided on the support plate 361 via pins 37f and 37g in a state in which it can be slightly moved along its long side direction (width direction of the continuous paper CP). The pins 37f and 37g are fixed by a retaining ring or the like in such a manner that they do not detach from the pressing plate 37a. As a portion bent downward from the pressing plate 37a, a head holding release portion 30 is formed. That is, the pressing plate 37a and the head holding release portion 30 are formed as one body. The head holding release portion 30 passes through the hole 36f formed in the support plate 361 and the hole 381b formed in the head attachment 38 (see Figure 9 ) so as to protrude from the head mechanism portion 35 in an operable manner.

[0127] The head holding release portion 30 is in the open position ( Figure 4 The user can pull the head assembly 18A out of the head mechanism portion 35 by operating the head holding release portion 30 in the +X direction.

[0128] A hole 36g is formed in the support plate 361 of the head holding portion 36, and a hole 37d is formed in the pressing plate 37a of the pin pressing portion 37. The pin 38P of the head assembly 18A passes through the hole 36g and the hole 37d and protrudes upward from the hole 37d.

[0129] The pressing plate 37a has a protrusion 37j that protrudes upward between the hole 37d and the pin 37g. A convex portion 37i that protrudes toward the protrusion 37j is formed on the edge of the hole 37d of the pressing plate 37a.

[0130] The coil spring 37b of the pin pressing portion 37 is installed between the pin 37g and the protrusion 37j. Figure 5 When the pressing plate 37a is pressed by the coil spring 37b, as in Figure 9 As shown in the enlarged cross-sectional view of FIG. 3 , the protrusion 37i engages with the recess 38Pr of the pin 38P projecting upward from the hole 37d. As a result, the pin 38P is locked by the pressing plate 37a, and the head assembly 18A is held by the head holding portion 36.

[0131] like Figure 7 and Figure 10 As shown, the pin pressing portion 37 includes a pin contact piece 37h. The pin contact piece 37h is located slightly closer to the -X side than the tapered portion 38Pt of the pin 38P that protrudes upward from the hole 37d. In other words, the pin contact piece 37h is located at a position where it contacts the tapered portion 38Pt of the pin 38P when the head holding release portion 30 is operated in the +X direction.

[0132] In order to release the head assembly 18A from being held by the head holding portion 36, the head holding release portion 30 is operated in the +X direction as described above. That is, the head holding release portion 30 of the pressing plate 37a is moved in the opposite direction (+X direction) to overcome the force of the coil spring 37b. As the pressing plate 37a moves in the +X direction, the pin contact piece 37h contacts the tapered portion 38Pt of the pin 38P, pressing the pin 38P downward, and the engagement between the concave portion 38Pr of the pin 38P and the convex portion 37i of the pin pressing portion 37 is released. As a result, the head assembly 18A falls due to its own weight.

[0133] The head cover 39 is configured to be swingable relative to the head holding portion 36 and covers at least a portion of the thermal head 18 from below. The head cover 39 has an insertion hole 395 through which the swing shaft 40 is inserted, and the head cover 39 is swingable about the swing shaft 40.

[0134] A pair of guide protrusions 393 are formed on both sides of the head cover 39. These guide protrusions 393 engage with the cutouts 382b of the head assembly 18A, thereby coupling the head assembly 18A to the head cover 39. As described above, the head cover 39 is supported by the swing shaft 40, and the thermal head 18 is coupled to the head cover 39. Therefore, the thermal head 18 is supported by the swing shaft 40.

[0135] The head cover 39 includes a front thermal head mounting portion 391 and a rear circuit board fixing portion 392. The head assembly 18A is mounted on the thermal head mounting portion 391. The circuit board fixing portion 392 is formed with a threaded portion 392a. The circuit board 50 is fixed by screwing a screw into the threaded portion 392a through the circuit board 50 (see FIG. Figure 7 ).

[0136] The head cover 39 houses a sensor assembly 53 including a light emitting element 611 of a light-transmitting sensor 61 (described later). Figure 10 and Figure 11 It can be seen that the sensor assembly 53 is housed in the head cover 39 so as to be arranged between the substrate 183 of the head assembly 18A and the head cover 39 .

[0137] exist Figure 11 and Figure 12 , a method of assembling the sensor assembly 53 to the head cover 39 is sequentially shown.

[0138] like Figure 11 As shown, the sensor assembly 53 includes a light emitting element 611, a wiring 613 connected to the light emitting element 611, a receiving member 55 (an example of a receiving portion) that receives the light emitting element 611, and a cover 54 that covers the receiving member 55. The wiring 613 extends outward from the receiving member 55 and is connected to the circuit board 50. The cover 54 of the sensor assembly 53 is provided with a shaft insertion portion 541 for inserting the swing shaft 40. The light emitting element 611 and the light receiving element 612 (see FIG. 1 ) described later are connected to each other. Figure 15 、 Figure 16 ) together constitute the light-transmitting sensor 61.

[0139] A sensor housing portion 397 is formed in the head cover 39, and the sensor assembly 53 is housed in the sensor housing portion 397. The head cover 39 is also provided with a through hole 39h, and light emitted from the light emitting element 611 passes through the head cover 39.

[0140] Although described later, the head cover 39 is movable forward and backward relative to the swing shaft 40. Meanwhile, the sensor assembly 53 is supported by the swing shaft 40 via the shaft insertion portion 541. Specifically, the light emitting element 611 is supported by the swing shaft 40. Therefore, the sensor assembly 53 is positioned within the sensor housing 397 of the head cover 39 so that the head cover 39 can move forward and backward relative to the sensor assembly 53. This improves space efficiency when arranging the light emitting element 611 near the heat generating portion 18L of the thermal head 18.

[0141] Reference Figure 12 As can be seen, the retaining member 56 is attached to the head cover 39 to prevent the sensor assembly 53 from detaching from the head cover 39. After the sensor assembly 53 is accommodated in the sensor accommodation portion 397, the screws 563 are fastened to the threaded holes 398 provided in the head cover 39 via two insertion holes 561 formed in the retaining member 56.

[0142] As described above, the light emitting element 611 is housed in the head cover 39 .

[0143] When the holding member 56 is attached to the head cover 39, the receiving member 55 guides the head cover 39 so that the head cover 39 can move in the front-back direction. Figure 13 The structure for realizing this guidance function will be described. Figure 13 The diagram includes a partial plan view of a portion where the sensor assembly 53 is disposed in the head cover 39 and a cross-sectional view taken along the line AA. The cross-sectional view shows the cross-sectional view taken along the line AA after the sensor assembly 53 and the holding member 56 are assembled to the head cover 39 .

[0144] like Figure 13 As shown in the top view of FIG, the portion of the head cover 39 where the sensor assembly 53 is located is formed with three protrusions 399 and a protrusion 390 that protrude upward from the bottom surface 39s of the head cover 39 and extend in the front-to-back direction. The protrusion 390 has bosses 390e formed at one end and the other end in the front-to-back direction. Each boss 390e is a cylindrical protrusion that is wider in the transverse direction than the portion connecting the two bosses 390e. Figure 13 As shown in the cross-sectional view of FIG, a groove 551 for accommodating the protrusion 390 is formed at the bottom of the accommodating member 55. The groove width of the groove 551 is equal to or slightly wider than the width of the boss 390e of the protrusion 390.

[0145] The holding member 56 is formed with three protrusions 562 that protrude downward from the upper surface 56 s and extend in the front-rear direction.

[0146] like Figure 13As shown in the cross-sectional view of FIG, when the sensor assembly 53 and the retaining member 56 are assembled to the head cover 39, the protrusion 399 of the head cover 39 abuts against the bottom surface of the receiving member 55, and the protrusion 562 of the retaining member 56 abuts against the upper surface of the cover 54. As a result, the movement of the sensor assembly 53 relative to the head cover 39 in the vertical direction is restricted.

[0147] Furthermore, the two bosses 390 e at the front and rear ends of the head cover 39 engage with the grooves 551 at the bottom of the receiving member 55 , thereby restricting the movement of the sensor assembly 53 in the lateral direction relative to the head cover 39 .

[0148] Meanwhile, the head cover 39 is capable of relative movement in the front-to-back direction relative to the sensor assembly 53. In this case, the protrusion 390 of the head cover 39 and the groove 551 of the receiving member 55 serve as guides for the head cover 39 as it moves in the front-to-back direction. Furthermore, to ensure the required relative movement of the head cover 39 in the front-to-back direction, the groove 551 is configured to have a length in the front-to-back direction that is sufficiently greater than the length of the protrusion 390 in the front-to-back direction.

[0149] Figure 14 Indicates from Figure 8 The head mechanism portion 35 is in a state where the head cover 39 is removed.

[0150] like Figure 14 As shown in FIG. 5 , the sensor assembly 53 is supported on the swing shaft 40 via the shaft insertion portion 541. Figure 8 As shown, in a state where the head cover 39 is mounted, a through hole 39 h for allowing light emitted from the light emitting element 611 in the sensor assembly 53 to pass therethrough is formed in the head cover 39 .

[0151] In addition, if Figure 5 As shown, a light receiving element 612 that receives light emitted from the light emitting element 611 is built into the label support portion 71 as will be described later. Since the light receiving element 612 is located downstream in the conveyance direction of the label guide portion 73, even if the sensor assembly 72 slides in the width direction of the continuous paper CP, light from the light emitting element 611 can reach the light receiving element 612 without being blocked.

[0152] As described above, the printer 1 includes the light-transmitting sensor 62 (see FIG. Figure 6), and two light-transmitting sensors: a light-emitting element 61 housed in the head cover 39 and a light-receiving element 612 built into the label support 71. Providing two light-transmitting sensors 61 and 62 at different positions in the conveyance direction allows for flexible application of any sensor depending on the accuracy required for the print start position for each label PL. The light-transmitting sensor 61 is an example of a first detection unit, and the light-transmitting sensor 62 is an example of a second detection unit.

[0153] Each light-transmitting sensor detects the edge of each label PL in the conveyance direction of the continuous paper CP. The output of the light-transmitting sensor is used for conveyance control to position the printing start position of each label PL at the position of the heating element 18L of the thermal head 18.

[0154] Next, refer to Figure 15 The positions of the two light transmission sensors 61 and 62 will be described. Figure 15 It is a cross-sectional view of the portion near the head cover 39 in the printer 1 .

[0155] exist Figure 15 In FIG. 1 , the sensor optical axis SL1 is a line connecting the light emitting element 611 and the light receiving element 612 of the light transmission type sensor 61. The sensor optical axis SL2 is a line connecting the light emitting element 621 and the light receiving element 622 (in FIG. 1 ) of the light transmission type sensor 62. Figure 15 That is, the light transmission sensor 62 (sensor optical axis SL2) is provided upstream in the conveyance direction of the continuous paper CP relative to the light transmission sensor 61 (sensor optical axis SL1).

[0156] like Figure 15 As shown, the light-emitting element 611 of the light-transmitting sensor 61 is positioned above the path along which the ink ribbon RB is conveyed from the tape supply unit 12a toward the platen roller 23. Meanwhile, the light-receiving element 612 of the light-transmitting sensor 61 is positioned within the label support unit 71, located below the path along which the continuous paper CP is conveyed toward the platen roller 23. Therefore, light emitted by the light-emitting element 611 is transmitted through the ink ribbon RB and the continuous paper CP and is received by the light-receiving element 612. This configuration allows the light-emitting element 611 and the light-receiving element 612 to be positioned close to the print position PP where the thermal head 18 and the platen roller 23 clamp the ink ribbon RB and the continuous paper CP, thereby improving the accuracy of the print start position for each label PL.

[0157] like Figure 15 As shown, the light emitting element 611 of the light transmission sensor 61 is arranged between the heat sink 181 of the thermal head 18 and the ink ribbon RB.

[0158] like Figure 15As shown, when the printer 1 is observed from the side, the direction from the position of the light emitting element 611 toward the position of the light receiving element 612 (i.e., the direction along the sensor optical axis SL1) is based on a virtual vertical line drawn from the position of the light emitting element 611 to the setting surface MS where the printer 1 is set, toward the side where the printing position PP is set.

[0159] like Figure 15 As shown, when the printer 1 is viewed from the side, the thermal head 18 becomes thinner as it moves in the direction opposite to the conveying direction of the ink ribbon RB (see also FIG. Figure 9 ), thereby forming a space between the thermal head 18 and the ink ribbon RB. Moreover, the light emitting element 611 is arranged in this space.

[0160] With this configuration, the light emitting element 611 is positioned particularly close to the print position PP, and accordingly, the light receiving element 612 is also positioned particularly close to the print position PP. This improves the accuracy of the print start position for each label.

[0161] The light receiving element 612 is arranged in the label support portion 71. That is, the light emitting element 611 is arranged on the upper side of the conveying path of the continuous paper CP toward the platen roller 23, and the light receiving element 612 is arranged on the lower side of the conveying path of the continuous paper CP. The reason for this is to stably receive the light emitted by the light emitting element 611. Since the label support portion 71 is arranged on the support platform 14 (refer to FIG. Figure 4 ) does not move, so the light receiving element 612 in the label support portion 71 can stably receive light. In contrast, the head cover 39 configured with the light emitting element 611 sometimes moves slightly due to the transmission of vibrations of the head assembly 18A accompanying the printing operation.

[0162] However, the arrangement of the light emitting element and the light receiving element in the light transmission sensor 61 is not limited thereto. The light emitting element 611 may be arranged below the conveyance path of the continuous paper CP, and the light receiving element 612 may be arranged above the conveyance path of the continuous paper CP.

[0163] like Figure 15 As shown, a transmissive sensor 62 (sensor optical axis SL2) is positioned upstream of the continuous paper CP conveyance path, and a transmissive sensor 61 (sensor optical axis SL1) is positioned downstream. However, the brightness of the light emitting elements in both sensors can be made different. The light emitted by the light emitting element 621 of the transmissive sensor 62 transmits only the continuous paper CP. In contrast, the light emitting element 611 of the transmissive sensor 61 transmits both the ink ribbon RB and the continuous paper CP. Furthermore, by varying the distance between the light emitting element and the light receiving element, the brightness of the light emitting element 611 can be made higher than that of the light emitting element 621, allowing for adjustment of the optimal brightness of each light emitting element.

[0164] Figure 16 It will Figure 15 FIG. 6 is an enlarged view of a portion related to the light-transmitting sensor 61 (light-emitting element 611 and light-receiving element 612 ).

[0165] like Figure 16 As shown, the light emitting element 611 is arranged on the substrate 611B, and the light receiving element 612 is arranged on the substrate 612B. The substrate 611B is fixed to the receiving member 55 (see Figure 11 The substrate 612B is disposed in the tag support portion 71.

[0166] A dustproof sheet 61L is attached to the support surface 711 of the label support 71. A thin passage 61P for light passage is formed from the sheet 61L along the sensor optical axis SL1. Light transmitted through the continuous paper CP along the sensor optical axis SL1 reaches the light receiving element 612 via the sheet 61L and the passage 61P. Alternatively, a lens may be used in place of the sheet 61L.

[0167] From the viewpoint of improving the detection accuracy of the light-transmitting sensor 61, it is preferred that the light-receiving element 612 is located on the same plane as the support surface 711, or is located near the support surface 711. That is, the length of the passage 61P is preferably extremely short. By arranging the light-emitting element 611 near the support surface 711, it is possible to give a large difference (contrast) in the light intensity of the light that passes through the label PL and the backing paper PM in the continuous paper CP transported on the support surface 711 and the light that passes through only the backing paper PM. In addition, as Figure 16 As shown, even when a relatively short passage 61P is provided from the support surface 711 to the light-receiving element 612, light once incident within the passage 61P does not further diverge, thereby posing no obstacle to achieving the aforementioned high contrast. Furthermore, since the light transmittance of the ink ribbon RB and / or continuous paper CP varies depending on their thickness and material, the brightness of the light emitted by the light-emitting element 611 can be appropriately adjusted to achieve optimal contrast.

[0168] That is, light is received by the light receiving element 612 of the light transmission sensor 61 at the support surface 711 of the label support 71 via the ink ribbon RB and the continuous paper CP from the light emitting element 611. Here, "light is received at the support surface 711" means that the light is received on the same plane as the support surface 711, or that the incident light from the support surface 711 is received via an optical path that does not significantly diffuse the light.

[0169] In one embodiment, Figure 16As shown, the conveyance path of the ink ribbon RB is located directly below the light emitting element 611. By positioning the light emitting element 611 as close to the ink ribbon RB as possible, the distance between the light emitting element 611 and the light receiving element 612 can be shortened, making it easier to adjust the brightness for obtaining the above-mentioned good contrast.

[0170] like Figure 15 As shown in FIG. 1 , the front portion of the head cover 39 is disposed between the substrate 183 of the thermal head 18 and the conveying path of the ink ribbon RB. The light emitting element 611 is housed in the sensor housing portion 397 ( Figure 11 ) and is arranged directly below the substrate 183 of the thermal head 18. In other words, the shape of the thermal head 18 is set so that the light emitting element 611 can be arranged directly below the substrate 183 of the thermal head 18, and the light emitting element 611, which is housed in the front portion of the head cover 39, is arranged in the space directly below the substrate 183. Therefore, the light emitting element 611 is arranged so as to be close to the printing position PP, thereby improving the accuracy of the printing start position for each label PL by the light transmission sensor 61.

[0171] like Figure 15 As shown, the transport path for the ink ribbon RB and the transport path for the continuous paper CP are configured to face downward as they move upstream from the printing position PP. Since the transport path for the ink ribbon RB and the transport path for the continuous paper CP face downward (i.e., toward the installation surface on which the printer 1 is installed) as they move upstream from the printing position PP, a space can be formed between the head cover 39 located behind the printing position PP and the transport paths, allowing the light emitting element 611 to be arranged near the heat generating portion 18L of the thermal head 18.

[0172] like Figure 15 As shown, the label guide 73 is configured to separate the conveying path of the continuous paper CP and the conveying path of the ink ribbon RB. Therefore, the ink ribbon RB from the belt roller 121 to the printing position PP and the ink ribbon RB from the damper 15 (see FIG. Figure 3 ,exist Figure 15 (Not shown) The continuous paper CP gradually approaches the printing position PP. Therefore, a predetermined distance can be maintained between the continuous paper CP and the ink ribbon RB at the position of the sensor optical axis SL1, thereby achieving the above-mentioned good contrast.

[0173] In one embodiment, the label guide 73 is positioned near the upstream side of the sensor optical axis SL1 in the conveyance direction. Because the label guide 73 guides the continuous paper CP from above (i.e., the label side), the amount of movement of the continuous paper CP in a direction perpendicular to the backing paper PM is limited (i.e., the wobbling of the continuous paper CP is suppressed). Consequently, the light receiving element 612 of the light transmission sensor 61, which is slightly downstream of the label guide 73, can receive light from the light emitting element 611 with minimal deviation, thereby improving the detection accuracy of the light transmission sensor 61.

[0174] Next, refer to Figure 17 The function of the head position adjustment mechanism is described below. As mentioned above, the head position adjustment refers to the operation of the operating unit 42 ( Figure 7 ) to adjust the position of the thermal head 18 back and forth.

[0175] Figure 17 The figure shows the head holding portion 36 and the head assembly 18A in the vicinity of the rotation shaft 41 as viewed from the side, and illustrates different positions P1 to P3 in the front-rear direction of the thermal head 18 .

[0176] In the rotating shaft 41, the fitting portion 41a that is inserted into the cutout portion 382a is eccentric relative to the central rotating shaft portion. Therefore, when the rotating shaft 41 is rotated by the operating portion 42, the fitting portion 41a describes a trajectory of displacement in the front-to-back direction, and according to this trajectory, the cutout portion 382a is displaced forward and backward (that is, the head assembly 18A is displaced forward and backward). Figure 17 , position P2 is a position where the fitting portion 41a is displaced rearward by L1 relative to position P1. Position P3 is a position where the fitting portion 41a is displaced rearward by L2 (> L1) relative to position P1.

[0177] When the head assembly 18A is displaced forward and backward by the head position adjustment mechanism, the head cover 39 connected to the head assembly 18A is also displaced forward and backward in conjunction with it, but the position of the light emitting element 611 does not change. Figure 18 Provide explanation.

[0178] Figure 18 : is a partial cross-sectional view showing the positional relationship of the periphery of the light transmission type sensor 61 before and after the head position adjustment. Figure 18 In FIG, the state before the head position is adjusted is indicated by a solid line, and the state after the head position is adjusted backward is indicated by a single-dot chain line. Figure 18 As shown in FIG, if the head position is adjusted backward, the head assembly 18A and the head cover 39 move backward in conjunction. Figure 10As shown, since the insertion hole 395 of the head cover 39 is formed as an elongated hole in the front-rear direction, the head cover 39 can move in the front-rear direction together with the head assembly 18A.

[0179] Even if the head assembly 18A and the head cover 39 move backward, the swing shaft 40 does not move because it is fixed to the internal frame (not shown). Figure 12 ) is guided in a manner capable of moving in the front-rear direction, but the receiving component 55 does not move because it is supported by the swing shaft 40 through the shaft insertion portion 541.

[0180] Therefore, even if the head assembly 18A is displaced forward and backward by the head position adjustment mechanism, the light emitting element 611 does not move forward and backward, so the light path emitted from the light emitting element 611 does not deviate, and the light receiving element 612 can stably receive light.

[0181] The position of the light emitting element 611 does not change with the movement of the head assembly 18A and the head cover 39, but the through hole 39h through which the light emitted by the light emitting element 611 passes moves forward and backward together with the head cover 39. Therefore, it is preferable that the through hole 39h is an elongated hole in the front-to-back direction so that even when the head cover 39 moves forward and backward, the light emitted by the light emitting element 611 can still reliably be directed toward the light receiving element 612. Figure 18 In the figure, OP1 represents the opening range of the through hole 39h in the longitudinal direction before the head position is adjusted, and OP2 represents the opening range of the through hole 39h in the longitudinal direction after the head position is adjusted backward. Because the through hole 39h is long in the front-to-back direction, the light emitted from the light emitting element 611 is not blocked when the through hole 39h is within either opening range OP1 or OP2 before or after the head position is adjusted.

[0182] As described above, in one embodiment, light from the light-emitting element is received by the light-receiving element of the light-transmitting sensor on the support surface of the label support unit via the ink ribbon and continuous paper. Because the ink ribbon and continuous paper are conveyed between the light-emitting element and the light-receiving element, the light-emitting element and the light-receiving element can be positioned immediately upstream of the printing position, thereby improving the accuracy of the printing start position for each label.

[0183] In one embodiment, the light receiving element is provided on a label support portion that supports the continuous paper from below the conveyance path. Since the label support portion does not move when printing on the continuous paper, it can stably receive light from the light emitting element.

[0184] In one embodiment, a light receiving element receives light from a light emitting element on a support surface supporting the continuous paper. This allows for a significant difference (contrast) in received light intensity between light transmitted through the ink ribbon and the continuous paper, light transmitted through the label and backing paper, and light transmitted through only the backing paper.

[0185] In one embodiment, the light-emitting element of the transmissive sensor is supported by a swing shaft inserted through the head cover. Therefore, even when the head assembly and head cover move forward and backward due to head position adjustment, the light-emitting element supported by the swing shaft does not move, ensuring stable light-emitting operation and preventing a decrease in tag detection accuracy.

[0186] While the embodiments of the printer of the present invention have been described above, the present invention is not limited to the above embodiments. Various improvements and modifications can be made to the above embodiments without departing from the spirit of the present invention.

[0187] The present invention relates to patent application No. 2023-54575 filed with the Japan Patent Office on March 30, 2023, and patent application No. 2024-46060 filed with the Japan Patent Office on March 22, 2024, the entire contents of which are incorporated herein by reference.

Claims

1. A printer, characterized in that: have: a conveying roller that conveys a continuous body and an ink ribbon, wherein the continuous body includes a strip-shaped backing paper and a plurality of printing media attached to the backing paper at intervals and in a releasable manner; a print head, which, at a printing position, clamps the ink ribbon and the continuum together with the conveying roller and prints information on each printing medium of the continuum; as well as The first detection unit is arranged on the upstream side of the conveying direction of the continuum relative to the printing position, has a light-emitting element and a light-receiving element that receives light from the light-emitting element via the ink ribbon and the continuum, and detects the end of each printing medium in the conveying direction of the continuum.

2. The printer according to claim 1, wherein: The printer includes a medium support portion having a support surface for supporting the continuous body toward the transport roller from a backing paper side. The light emitting element is arranged on a side where the print head is provided with respect to a conveying path of the ink ribbon toward the conveying roller. The light receiving element receives light at the supporting surface.

3. The printer according to claim 1, wherein: The print head has a substrate provided with a heating portion, The light emitting element is arranged directly below the substrate.

4. The printer according to claim 1, wherein The print head has a heat dissipation portion, The light emitting element is disposed between the heat dissipation portion and the ink ribbon.

5. The printer according to claim 1, wherein: When the printer is viewed from the side, the direction from the position of the light emitting element toward the position of the light receiving element is toward the side where the printing position is set, based on a virtual perpendicular line drawn from the position of the light emitting element to the installation surface where the printer is set.

6. The printer according to claim 1, wherein: When the printer is viewed from the side, the print head becomes thinner as it moves in a direction opposite to the conveying direction of the ink ribbon, thereby forming a space between the print head and the ink ribbon. The light emitting element is disposed in the space.

7. The printer according to claim 1, wherein: The printer is configured such that a conveyance path for the ink ribbon and a conveyance path for the continuous body are directed toward an installation surface on which the printer is installed as they move upstream from the printing position.

8. The printer according to claim 3, wherein: The printer includes a head cover disposed between the substrate and the conveyance path of the ink ribbon. The light emitting element is housed in the head cover.

9. The printer according to claim 8, characterized in that The head cover is formed with a through hole for allowing light emitted by the light emitting element to pass therethrough.

10. The printer according to any one of claims 1 to 9, characterized in that: A guide portion is provided on the upstream side of the light receiving element in the conveyance direction, the guide portion guiding the continuous body toward the conveyance roller from the printing medium side.

11. The printer according to any one of claims 1 to 9, characterized in that: The printer includes a second detection unit, which is provided upstream of the first detection unit in the conveyance direction of the continuous body and detects an end portion of each printing medium in the conveyance direction of the continuous body. The second detection unit includes a light emitting element and a light receiving element. The element located farther from the installation surface of the printer is arranged between the conveyance path of the ink ribbon and the conveyance path of the continuous body.

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