printer

Abstract

A printer according to an aspect of the present invention is for performing printing on a printing medium having an RFID inlay, and comprises: a platen roller that conveys the printing medium; a printing head that has a heating unit formed of a plurality of heat generators arranged in a linear manner and that performs printing on the printing medium while holding the printing medium between the heating unit and the platen roller; a wireless antenna disposed, at a location on the downstream side of a conveyance path for the printing medium with respect to the heating unit of the printing head, on the printing surface side of the conveyed printing medium; and a reader / writer that communicates with the RFID inlay of the printing medium through the wireless antenna.

Description

printer

[0001] The present invention relates to a printer.

[0002] Conventionally, printers that print on labels incorporating an RFID (Radio Frequency Identification) inlay (hereinafter simply referred to as "inlay") having an IC chip and an antenna have been known. When printing on a label, such printers use a reader / writer built into the printer to read and write data from and to the inlay incorporated in the label. To read and write data from and to the inlay, the reader / writer is connected to an RFID antenna that transmits and receives radio waves.

[0003] In conventional printers, the RFID antenna is positioned upstream of the label transport path relative to the position where the heating element of the print head is formed (see FIG. 4 of JP 2020-157521 A).

[0004] When the RFID antenna is located upstream of the label transport path relative to the location where the print head's heating element is formed (heating element position), as in conventional printers, the first label may be wasted. This problem is explained below.

[0005] Typically, when printing multiple consecutively arranged labels, the printer waits with the print start position of the first label positioned at the heater element of the print head. When printing each label, the printer reads and writes data from the inlay of each label before printing. If the RFID antenna is located upstream of the heater element, the label must be reversed so that it is positioned appropriately for reading and writing data from the inlay of the first label. However, especially for labels with a small pitch (short length in the feed direction), reverse feeding the first label can cause the leading edge of the first label to fall off the heater element of the print head. Positioning the RFID antenna close to the heater element on the label feed path would prevent the leading edge of the first label from falling off the heater element of the print head, but the structure of the print head makes it difficult to position the RFID antenna close enough to the heater element. For this reason, the conventional practice is to discard the first label and start printing from the second label. This problem is particularly likely to occur in the case of small-pitch labels or when the RFID antenna is located far from the heating element.

[0006] Furthermore, for the second and subsequent labels, each label must be conveyed backward to read and write data from and to the inlay, but if the RFID antenna is located far from the heating element, the distance the label must be conveyed backward to read and write data becomes long, reducing throughput. However, as mentioned above, due to the structure of the print head, it is difficult to bring the RFID antenna close enough to the heating element, so there is a limit to how much throughput can be improved.

[0007] SUMMARY OF THE INVENTION Therefore, an object of the present invention is to prevent the first sheet of print media from going to waste when multiple sheets of print media each having an RFID inlay are issued in sequence.

[0008] One aspect of the present invention is a printer that prints on a print medium having an RFID inlay, comprising: a platen roller that transports the print medium; a print head that has a heating section consisting of a plurality of heating elements arranged in a line and prints on the print medium while holding the print medium between the heating section and the platen roller; a wireless antenna that is located downstream of the heating section of the print head in the transport path of the print medium and on the printing surface side of the transported print medium; and a reader / writer that communicates with the RFID inlay on the print medium via the wireless antenna.

[0009] According to one aspect of the present invention, when a plurality of sheets of print media each having an RFID inlay are issued in sequence, it is possible to prevent the first sheet of print media from going to waste.

[0010] 1 is a perspective view of a printer according to an embodiment; FIG. 2 is a side view of a printer according to an embodiment with the interior visible; FIG. 3 is a perspective view of a printing section of a printer according to an embodiment with the print head unit in an open state; FIG. 4 is a perspective view of a label support mechanism of a printer according to an embodiment; FIG. 5 is a partial cross-sectional view of the label support mechanism of a printer according to an embodiment; FIG. 6 is a perspective view of a portion of a head mechanism of a printer according to an embodiment, viewed from below; FIG. 7 includes an exploded perspective view of a head assembly incorporated into the head mechanism and a cross-sectional view of a thermal head; FIG. 8 is an exploded perspective view of a portion of the head mechanism of FIG. 6; FIG. 9 is a diagram illustrating a method of mounting an RFID antenna in a printer according to an embodiment; FIG. 10 is a perspective view of a printer according to an embodiment with the RFID antenna attached to a ribbon adjustment plate; FIG. 11 is a partial cross-sectional view of a printer according to an embodiment; FIG. 12 is a partial side view of a printer according to an embodiment with the interior visible, showing a wiring path between the RFID antenna and a reader / writer; FIG. 13 is a schematic block diagram of a printer according to an embodiment; FIG. 14 is a diagram illustrating an example of transport control of a printer according to an embodiment; FIG. 15 is a diagram illustrating an example of transport control of a printer according to an embodiment; FIG. 16 is a diagram illustrating an RFID antenna arranged in a head holding unit in a printer according to a modified example. 19A is a diagram showing an RFID antenna arranged at the tip of a thermal head in a printer according to a modified example; FIG. 21B is a diagram showing an RFID antenna arranged at the bottom of a thermal head in a printer according to a modified example; FIG. 21C is a diagram showing an RFID antenna arranged in an opening provided in a thermal head in a printer according to a modified example; FIG. 21D is a diagram showing an RFID antenna arranged in a head accessory member in a printer according to a modified example; FIG. 21E is a diagram showing a side view of the front part of the head accessory member when the head accessory member shown in FIG. 19A is mounted on a printer; FIG. 21F is a diagram showing an RFID antenna arranged in a position close to a label presence / absence detection sensor in a printer according to a modified example; FIG. 21G is a perspective view of a printer according to a modified example; FIG. 21H is a diagram showing an RFID antenna arranged near the cutter or downstream of the cutter in the printer shown in FIG.

[0011] The embodiments described below are not limited to the drawings described by the brief description of the drawings.

[0012] A first aspect of the present invention is a printer that prints on a print medium having an RFID inlay, comprising: a platen roller that transports the print medium; a print head that has a heat generating section consisting of a plurality of heat generating elements arranged in a line and that prints on the print medium while holding the print medium between the heat generating section and the platen roller; a wireless antenna that is located downstream of the heat generating section of the print head in the transport path of the print medium and on the printing surface side of the print medium being transported; and a reader / writer that communicates with the RFID inlay on the print medium via the wireless antenna.

[0013] According to a first aspect of the present invention, when a plurality of print media each having an RFID inlay are issued in sequence, it is possible to prevent the first print medium from going to waste.

[0014] A second aspect of the present invention is the printer according to the first aspect, wherein the print head has a head body and a heat dissipation unit attached to the head body, and the wireless antenna is attached to the heat dissipation unit.

[0015] According to a second aspect of the present invention, the wireless antenna can be integrated with the print head, and the wireless antenna can be accurately positioned downstream of the heat generating portion of the print head.

[0016] A third aspect of the present invention is the printer according to the first aspect, further comprising a head assembly including the print head, and the wireless antenna is attached to the head assembly.

[0017] According to a third aspect of the present invention, the wireless antenna can be integrated with the print head, and the wireless antenna can be accurately positioned downstream of the heat generating portion of the print head.

[0018] A fourth aspect of the present invention is the printer according to the first aspect, further comprising: a head assembly including the print head; and a head holder that detachably holds the head assembly, wherein the wireless antenna is attached to the head holder.

[0019] According to a fourth aspect of the present invention, the wireless antenna can be accurately positioned downstream of the heat generating portion of the print head.

[0020] A fifth aspect of the present invention is the printer according to the first aspect, wherein the print head prints on the print medium while sandwiching the print medium and ink ribbon between the heat generating portion and the platen roller, the printer includes a ribbon adjustment portion that adjusts the tension of the ink ribbon downstream of the ink ribbon transport path, and the wireless antenna is attached to the ribbon adjustment portion.

[0021] According to a fifth aspect of the present invention, since the wireless antenna is arranged separately from the print head, there is no need to remove the wireless antenna when replacing the print head.

[0022] A sixth aspect of the present invention is a printer described in any one of the first to fifth aspects, which is equipped with a control unit that controls the reader / writer to communicate with the RFID inlay of the printing medium when the printing medium is transported to a communication position where the distance from the reference position of the wireless antenna to the reference position of the RFID inlay of the printing medium is a predetermined value in the transport direction of the printing medium.

[0023] According to a sixth aspect of the present invention, the printing medium is transported toward a wireless antenna located downstream of the heat generating portion on the transport path of the printing medium before communication is performed, so that the first sheet of printing medium does not fall off the printing medium.

[0024] A seventh aspect of the present invention is the printer according to the first aspect, further comprising a cutting section that cuts the print medium downstream of the heat generating section of the print head in the transport path of the print medium, and the wireless antenna is positioned near the cutting section or downstream of the cutting section.

[0025] According to a seventh aspect of the present invention, since the wireless antenna is arranged separately from the print head, there is no need to remove the wireless antenna when replacing the print head.

[0026] An embodiment will be described in detail below with reference to the drawings. FIG. 1 shows the external appearance of a printer 1 according to one embodiment. For ease of explanation, XYZ coordinates will be defined below as shown in FIG. 1. That is, +X and -X respectively indicate the left-right direction of the printer 1, +Y and -Y respectively indicate the front-rear direction of the printer 1, and +Z and -Z respectively indicate the up-down direction of the printer 1. A front cover 2 on the front side of the printer 1 is provided with an issuing port 5 for issuing (discharging) printed labels. An open cover 6 is attached to one side of the printer 1 by two hinges 7 so that it can be opened and closed in the up-down direction.

[0027] Figure 2 is a side view of the main parts of the printer 1 with the interior visible. Figure 3 is a perspective view of the printing unit 11 when the print head unit 13 is in the open state. Inside the printer 1, there are a paper supply unit 10 located at the rear, a printing unit 11 located at the front, and an ink ribbon unit 12 located above.

[0028] The paper supply unit 10 is loaded with roll paper R. As shown in FIG. 2 , the roll paper R is a roll of continuous paper CP. The continuous paper CP includes a strip-shaped backing paper PM and multiple labels PL removably attached to the backing paper PM at intervals. The surface (front side) of the backing paper PM that contacts the adhesive surface of the labels PL is coated with a release agent such as silicone, allowing the labels PL to be easily removed. The labels PL incorporate an RFID inlay IL (hereinafter simply referred to as "inlay IL"). The surface (back side) of the backing paper PM that does not have the labels PL attached thereto may be formed with position detection marks IM at predetermined intervals along the length to indicate the position of the labels. The labels PL may be thermal paper or plain paper. In the case of thermal paper, a thermosensitive coloring layer is formed on the surface that turns a specific color (such as black or red) when it reaches a predetermined temperature range. Although not shown, the paper supply unit 10 can also be loaded with roll paper that is made up of linerless labels wound into a roll and having an adhesive surface with an adhesive applied to the back of the printing surface.

[0029] The paper supply unit 10 includes a support shaft 10a and a roll guide 10b, and holds the roll paper R and supplies the continuous paper CP fed from the roll paper R to the printing unit 11. The support shaft 10a supports the roll paper R in a freely rotatable state. The roll guide 10b is installed in a freely movable state 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.

[0030] The printing unit 11 includes a print head unit 13, a support base 14 disposed below the print head unit 13, and a damper 15. It prints on labels PL on the continuous paper CP. The print head unit 13 is installed inside the printer 1 in a state in which it can be freely opened and closed, as described below. When the print head unit 13 is closed, a paper passage route is formed between the print head unit 13 and the support base 14. The paper passage route is connected to the paper issuing port 5 (see FIG. 1). A head lock lever 16 is installed on the support base 14 to keep the print head unit 13 in a closed state. Operating the head lock lever 16 releases the print head unit 13 from its closed state, lifting the front portion of the print head unit 13 as shown in FIG. 3, and opening the print head unit 13 (moving away from the platen roller 23). The damper 15 is installed in a state in which it can be freely swung so that it can apply tension to the continuous paper CP.

[0031] 2 and 3, the continuous paper CP is transported from the damper 15 through the label support mechanism 70, and after printing, is discharged from the issuing port 5 (FIG. 1). The label support mechanism 70 is installed upstream of the thermal head 18 (an example of a print head) and the platen roller 23 in the transport path of the continuous paper CP.

[0032] The ink ribbon unit 12 includes a ribbon supply unit 12a and a ribbon take-up unit 12b, and supplies and takes up the ink ribbon RB coated with printing ink. The ribbon supply unit 12a supports the ink ribbon RB taken up in a roll so that it can rotate freely. The ribbon take-up unit 12b takes up and collects the ink ribbon RB after printing. When the ink ribbon RB is used, the ink ribbon RB pulled out from the ribbon supply unit 12a is passed under the print head unit 13 and taken up by the ribbon take-up unit 12b. The ribbon supply unit 12a and the ribbon take-up unit 12b are connected (attached) to the inner wall 102 of the housing of the printer 1.

[0033] As shown in Figure 3, a ribbon adjustment plate 66 (an example of a ribbon adjustment section) is installed in front of the thermal head 18 in the print head unit 13. The ribbon adjustment plate 66 is fixed to the internal frame (not shown) by a pair of screws 664 that pass through elongated holes (elongated holes 665 in Figure 10) formed on both ends. By loosening each of the screws 664, the ribbon adjustment plate 66 can be moved up and down or tilted left and right, thereby adjusting the tension of the ink ribbon RB.

[0034] In the printer 1, the continuous paper CP fed from the roll paper R in the paper supply unit 10 is transported via the damper 15 to the paper passage route between the print head unit 13 and the support table 14, and along the way, the labels PL of the continuous paper CP are printed. At this time, the thermal head 18 prints on each label PL of the continuous paper CP while holding the continuous paper CP and ink ribbon RB between the heat generating part 18L and the platen roller 23. After the printing process, the continuous paper CP is discharged from the printer 1 through the issue port 5.

[0035] As shown in Figure 2, a label presence detection sensor 64 is installed near the issuing port 5 of the printer 1. The label presence detection sensor 64 is located downstream of the thermal head 18 and is capable of detecting the label PL issued (discharged) from the issuing port 5. The label presence detection sensor 64 is a light reflective sensor, but can also be configured as a light transmissive sensor. The detection result (output signal) of the label presence detection sensor 64 is used to control the transport of the continuous paper CP.

[0036] Next, the configuration of the printing unit 11 will be described with reference to Fig. 3. As shown in Fig. 3, the print head unit 13 is supported on a main frame (not shown) of the printer 1 so that the print head unit 13 can freely swing (i.e., open and close) around the X axis around the swing shaft S1 provided at the rear.

[0037] A thermal head 18 is installed on the underside (the surface facing the paper feed route) of the print head unit 13, with its heat generating portion 18L facing the paper feed route. The heat generating portion 18L of the thermal head 18 is composed of a glaze layer that protrudes a predetermined amount (for example, several tens of μm) from the substrate of the thermal head 18, and includes multiple heat generating resistors (heat elements) that generate heat when energized, and prints on the labels PL of the continuous paper CP. These multiple heat generating resistors are aligned in the width direction of the continuous paper CP (the direction perpendicular to the transport direction of the continuous paper CP).

[0038] A pair of engagement claws 19 (see FIG. 3) are provided on the underside of the front side of the print head unit 13 so as to sandwich the thermal head 18. Behind the engagement claws 19 of the print head unit 13, pins 20 are provided that protrude outward from both side surfaces of the print head unit 13.

[0039] The print head unit 13 is biased in the open direction by a torsion spring (not shown) attached to the pivot shaft S1, but is maintained in a closed state by a pair of locking claws 22 on the support base 14 that engage with a pair of pins 20 on the bottom of the print head unit 13. When the print head unit 13 is closed, a pair of engagement claws 19 on the print head unit 13 fit into both ends of the rotation shaft of the platen roller 23. When the head lock lever 16 is operated rearward, the locking claws 22 move rearward in conjunction with this and disengage from the pin 20. When the locking claws 22 disengage from the pin 20, the print head unit 13 automatically opens due to the biasing force of the torsion spring, as shown in Figure 3.

[0040] The platen roller 23 transports the continuous paper CP fed from the paper supply unit 10 along the paper passage route to the issue port 5 (see FIG. 1). The platen roller 23 is installed on top of the support base 14 in a state where it can rotate in both forward and reverse directions, and during printing, it rotates together with the thermal head 18 while sandwiching the continuous paper CP. If the continuous paper CP is plain paper, the platen roller 23 rotates together with the thermal head 18 while sandwiching the continuous paper CP and the ink ribbon RB during printing. In this case, the ink ribbon RB is transported from the ribbon supply unit 12a via ribbon rollers 121, 122 (see FIG. 3) provided in the print head unit 13 and is taken up by the ribbon take-up unit 12b.

[0041] As shown in FIG. 3 , the label support mechanism 70 is disposed on the support base 14. FIG. 4 shows perspective views of the label support mechanism 70 in both the narrow label guide position and the wide label guide position. As shown in FIG. 4 , the label support mechanism 70 includes a label support unit 71, a sensor assembly 72, and a label guide unit 73. The label support unit 71 has a support surface 711 that supports the continuous paper CP from below as it approaches the platen roller 23. The sensor assembly 72 is attached to the label support unit 71 so as to be slidable in the width direction of the continuous paper CP and incorporates a light transmission sensor and a reflective sensor. The label guide unit 73 is attached to the sensor assembly 72 and serves to sandwich the continuous paper CP being transported toward the platen roller 23 between itself and the support surface 711 of the label support unit 71, guiding the continuous paper CP from above. The label support mechanism 70 incorporates a reader / writer 91, which will be described later. The reader / writer 91 is provided to write data to an inlay IL incorporated in a label PL or to read data from the inlay IL.

[0042] FIG. 5 shows a schematic cross section of the sensor assembly 72 and the label guide unit 73 when the label support mechanism 70 is cut along a plane perpendicular to the surface of the transported web paper CP and extending in the width direction (X direction) of the web paper CP. As shown in FIG. 5, the label guide unit 73 is attached to the sensor assembly 72. A small gap g1 is formed between the underside of the label guide unit 73 and the support surface 711 of the label support unit 71, and this gap g1 forms a transport path for the web paper CP. The label support unit 71 is provided with a guide protrusion 712 and a guide groove 713 in the longitudinal direction that engage with the sensor assembly 72. The sensor assembly 72 is slidable in the longitudinal direction (i.e., the width direction of the web paper CP) while engaging with the guide protrusion 712 and the guide groove 713 of the label support unit 71 according to the label width used. The sensor assembly 72 has a structure in which an upper swinging part 721 and a lower sliding part 722 are swingably connected by a swing shaft 723. The sliding part 722 is engageable with a guide protrusion 712 and a guide groove 713 of the label support part 71 and is slidable in the longitudinal direction. The swinging part 721 can swing about the swing shaft 723 from a position shown in FIG. 5 (the position when the printer 1 is operating) in which it is close to the sliding part 722, to a direction away from the sliding part 722 (i.e., counterclockwise in FIG. 5), thereby allowing a new continuous paper CP to be set in the printer 1.

[0043] As shown in FIG. 5 , the sensor assembly 72 has a built-in label position detection sensor 74. The label position detection sensor 74 includes a light-emitting element 621 and a light-receiving element 622. The light-emitting element 621 is disposed on the swinging portion 721, and the light-receiving element 622 is disposed on the sliding portion 722. The light-emitting element 621 and the light-receiving element 622 face each other. Because the transport path of the ink ribbon RB is located above the label guide portion 73, the light-emitting element 621, which is located above the light-receiving element 622, is disposed between the transport path of the ink ribbon RB and the transport path of the continuous paper CP. When the light-receiving element 622 receives light emitted from the light-emitting element 621, the optical transmission sensor 62 detects the edge of each label PL in the transport direction of the continuous paper CP based on the difference in received light intensity between light that has passed through the label PL and the liner PM and light that has passed only through the liner PM. The detection result (output signal) of the label position detection sensor 74 is used to control the transport of the continuous paper CP.

[0044] Next, the head mechanism 35 provided in the print head unit 13 will be described with reference to Figures 6 to 8. The head mechanism 35 is a mechanism associated with the thermal head 18 when the support plate 17, ribbon rollers 121 and 122, swing shaft S1, etc. have been removed from the print head unit 13. Figure 6 is a perspective view of the main parts of the head mechanism 35 as seen from below. As shown in Figure 6, the head mechanism 35 includes the thermal head 18, a head holder 36, a pin pressing unit 37 (not visible in Figure 6), a head cover 39, a swing shaft 40, a rotation shaft 41, etc.

[0045] Although not visible in FIG. 6 , a head attachment member 38 is fixed to the thermal head 18. FIG. 7 includes an exploded perspective view showing how the thermal head 18 and head attachment member 38 are attached, as well as a cross-sectional view of the thermal head 18 (a cross-sectional view cut at the center in the longitudinal direction). As shown in FIG. 7 , the head attachment member 38 is a plate-shaped member including a center plate 381 and a pair of end plates 382. A pin 38P is attached to the top surface of the center plate 381, protruding upward. The pin 38P has a columnar portion 38Pc extending upward from the surface of the center plate 381 and a tapered portion 38Pt tapering from the top of the columnar portion 38Pc. A recess 38Pr is formed in the columnar portion 38Pc, recessed toward the +X side. As will be described later, the pin 38P is necessary for holding the thermal head 18 in the head holder 36.

[0046] The thermal head 18 includes a heat sink 181, a substrate 183, and a connector 184. The substrate 183 may have two or more substrates connected thereto and is formed with the heat generating portion 18L described above. The heat sink 181 is provided to efficiently dissipate heat generated by the substrate 183. Two screw holes 181a are formed in the heat sink 181. As shown in the cross-sectional view of the thermal head 18 in FIG. 7 , the substrate 183 includes a first substrate portion 183a on which the heat generating portion 18L is disposed, a second substrate portion 183b connected to the connector 184, and a flexible substrate portion 183c connecting the first substrate portion 183a and the second substrate portion 183b. The heat sink 181 is designed to be thickest at the first substrate portion 183a of the substrate 183 so as to efficiently dissipate heat from the first substrate portion 183a, which generates the most heat. A protrusion 1811 that protrudes downward so as to cover the tip of the first substrate portion 183a is formed at the tip of the heat sink 181. This prevents jams from occurring when the continuous paper CP (especially thick paper) is backfed (conveyed in the reverse direction).

[0047] As shown in Figure 7, two holes 381a are formed in the center plate 381 of the head accessory 38, and screws 383 are fastened through these holes 381a into the screw holes 181a of the thermal head 18, thereby fixing the head accessory 38 to the thermal head 18. In the following description, the thermal head 18 and the head accessory 38 integrated together will be referred to as the "head assembly 18A" where appropriate. The head assembly 18A is detachable from the head cover 39. Two holes 381a are formed in the center plate 381 of the head accessory 38, and screws 383 are fastened through these holes 381a into the screw holes 181a of the thermal head 18, thereby fixing the head accessory 38 to the thermal head 18.

[0048] A pair of notches 382a are formed at the front ends of the end plates 382 on both sides of the head accessory 38. The notches 382a have a U-shape that opens upward. As will be described later, the notches 382a are provided for adjusting the front-to-rear position of the thermal head 18. A notch 382b is formed at the rear end of the end plates 382 on both sides of the head accessory 38. The notches 382b have a U-shape that sandwiches the guide protrusions 393 of the head cover 39.

[0049] Next, the configuration of the main parts of the head mechanism 35 will be described with reference to FIG. 8 . FIG. 8 is an exploded perspective view of the head mechanism 35 shown in FIG. 6 . A circuit board connected to the connector 184 of the thermal head 18 is fixed to the head cover 39, but this is not shown in FIG. 8 for clarity of the head cover 39. As shown in FIG. 8 , the head mechanism 35 is configured by, from top to bottom, assembling a head holding part 36, a head assembly 18A, and a head cover 39. The head holding part 36 and the head cover 39 are supported by a swing shaft 40. The swing shaft 40 is supported by the support plate 17 (see FIG. 3 ) and is fixed to an internal frame (not shown) located inside the support plate 17 and integrally formed with the support plate 17.

[0050] The head holding portion 36 holds the head assembly 18A to prevent it from falling under its own weight, and releases its hold on the head assembly 18A in response to operation of the head holding release portion 30 in the +X direction. Operating the head holding release portion 30 allows the head assembly 18A to be easily removed from the head holding portion 36. The head holding portion 36 includes a plate-like member including a support plate 361 and side walls 362 provided on both left and right ends of the support plate 361, as well as a pin pressing portion 37, and removably holds the head assembly 18A. A pair of engagement claws 19 that engage with both ends of the rotation shaft of the platen roller 23 are formed at the front ends of the side walls 362 on both sides of the head holding portion 36. Insertion holes 362a, 362b through which the swing shaft 40 is inserted are formed at the rear ends of the side walls 362 on both sides of the head holding portion 36.

[0051] The operating unit 42 is a rotation operating device for adjusting the position of the thermal head 18 in the forward and backward directions by moving the head assembly 18A forward and backward. Here, the forward and backward direction refers to the direction in which the printed label PL advances with the thermal head 18. The forward and backward adjustment of the position of the thermal head 18 is performed to obtain optimal print quality depending on the type of label (e.g., thickness, hardness, etc.). A rotating shaft 41 that rotates in response to rotation of the operating unit 42 is supported on side walls 362 on both sides of the support plate 361 of the head holding unit 36. U-shaped notches 382a on both ends of the head assembly 18A fit into both ends of the rotating shaft 41 from below, thereby engaging the head assembly 18A with the rotating shaft 41.

[0052] The pin pressing unit 37 includes a pressure plate 37a and a coil spring 37b. When the head assembly 18A is held by the head holding unit 36, the pin pressing unit 37 presses the pin 38P of the head assembly 18A. The pressure plate 37a is mounted on the support plate 361 by pins 37f and 37g, allowing it to move slightly along its longitudinal direction (the width direction of the web paper CP). The pins 37f and 37g are secured to the pressure plate 37a with retaining rings or the like to prevent it from slipping out. The head release unit 30 is formed as a portion bent downward from the pressure plate 37a. In other words, the pressure plate 37a and the head release unit 30 are integrally molded. The head release unit 30 penetrates a hole 36f formed in the support plate 361 and a hole 381b (see FIG. 7) formed in the head accessory member 38, protruding from the head mechanism unit 35 for operation. A hole 36g is formed in the support plate 361 of the head holding portion 36, and a hole 37d is formed in the presser plate 37a of the pin pressing portion 37. The pin 38P of the head assembly 18A passes through the holes 36g and 37d and protrudes upward from the hole 37d. A protrusion 37j that protrudes upward is formed on the presser plate 37a between the hole 37d and the pin 37g. A convex portion 37i that is convex toward the protrusion 37j is formed on the presser plate 37a at the edge of the hole 37d. The coil spring 37b of the pin pressing portion 37 is attached between the pin 37g and the protrusion 37j. The presser plate 37a is biased in the -X direction by the coil spring 37b. When the presser plate 37a is biased by the coil spring 37b, the protrusion 37i engages with the recess 38Pr of the pin 38P protruding upward from the hole 37d, as shown in the enlarged cross-sectional view of "the state in which the pin 38P is engaged" in Figure 8. This locks the pin 38P to the presser plate 37a, and the head assembly 18A is held by the head holding portion 36.

[0053] 8, the pin pressing portion 37 has a pin abutment piece 37h. The pin abutment piece 37h is positioned slightly on the -X side from the tapered portion 38Pt of the pin 38P that protrudes upward from the hole 37d. In other words, the pin abutment piece 37h is positioned so that it abuts against the tapered portion 38Pt of the pin 38P when the head hold release portion 30 is operated in the D1 direction (+X direction).

[0054] To release the head assembly 18A from the head holding portion 36, the head release portion 30 is operated in the +X direction as described above. That is, the head release portion 30 of the presser plate 37a is moved in the opposite direction (+X direction) against the biasing force of the coil spring 37b. As the presser plate 37a moves in the +X direction, the pin abutment piece 37h abuts against the tapered portion 38Pt of the pin 38P, pressing down the pin 38P, and the engagement between the recess 38Pr of the pin 38P and the protrusion 37i of the pin pressing portion 37 is released. As a result, the head assembly 18A falls under its own weight.

[0055] The head cover 39 is pivotable relative to the head holding portion 36 and is configured to cover at least a portion of the thermal head 18 from below. The head cover 39 has an insertion hole 395 through which the pivot shaft 40 passes, allowing it to pivot around the pivot shaft 40. A pair of guide protrusions 393 are formed on both sides of the head cover 39. These guide protrusions 393 engage with the cutout portions 382b of the head assembly 18A, thereby connecting the head assembly 18A and the head cover 39. The guide protrusions 393 allow the head assembly 18A to be smoothly inserted and removed from the printer 1.

[0056] The head cover 39 includes a front thermal head mounting portion 391 and a rear circuit board fixing portion 392. The head cover 39 of the head assembly 18A is mounted on the thermal head mounting portion 391. A threaded portion 392a is formed on the circuit board fixing portion 392, and a circuit board (not shown) connected to the connector 184 of the thermal head 18 is fixed by threading a screw into the threaded portion 392a via the circuit board.

[0057] Next, the arrangement of the RFID antenna 311 (an example of a wireless antenna) that transmits electromagnetic waves to the inlay IL incorporated in each label PL of the continuous paper CP transported within the printer 1 will be described with reference to FIGS. 9 and 10 . FIG. 9 is a diagram illustrating a method for mounting the RFID antenna 311 in the printer 1. Referring to FIG. 9 , the antenna assembly 31 includes the RFID antenna 311, wiring 312, and a pair of mounting members 313. The wiring 312 is connected to one end of the RFID antenna 311 and is used for electrical connection with the reader / writer 91, which will be described later. The pair of mounting members 313 are used to improve the ease of assembly of the antenna assembly 31 into the antenna case 32.

[0058] The antenna case 32 is a member for housing the antenna assembly 31. As will be described later, the antenna case 32 is attached to the ribbon adjustment plate 66. As shown in Fig. 9, the antenna case 32 has an elongated case main body 321 and three protrusions 322 that protrude upward from the case main body 321. Engagement claws 322c are formed on the upper ends of the protrusions 322.

[0059] The case body 321 has a generally U-shaped cross section so that the antenna assembly 31 can be received from one side. The case body 321 is formed with a pair of openings 3211 for receiving the pair of mounting members 313 of the antenna assembly 31, respectively. The interior of the case body 321 is formed with a mounting surface 3212 for mounting the RFID antenna 311, and is provided with stoppers 3213 for abutting against the RFID antenna 311 and the mounting members 313 to position the antenna assembly 31 in the X direction. The interior of the case body 321 is provided with a plurality of pressing portions 3214 for pressing the RFID antenna 311 from above, and a plurality of press-fit portions 3215 for press-fitting the wiring 312. When the antenna assembly 31 is assembled to the antenna case 32, the antenna assembly 31 is held by the antenna case 32 and does not move relative to the antenna case 32.

[0060] As shown in FIG. 10A , the antenna case 32 that holds the antenna assembly 31 is attached to the rear surface of the ribbon adjustment plate 66. The ribbon adjustment plate 66 has a flat portion 661 that extends laterally and a groove portion 662 that is formed by bending the flat portion 661 at its lower end. Three holes 663 are formed in the flat portion 661. The antenna case 32 is attached to the ribbon adjustment plate 66 by engaging the three engagement claws 322c of the antenna case 32 with the three holes 663, respectively, and by engaging a portion of the case body 321 of the antenna case 32 with the groove portion 662 (see FIG. 10B ).

[0061] FIG. 10B shows a cross section of the printer 1 near the RFID antenna 311 when the RFID antenna 311 is installed. As shown in FIG. 10B , the RFID antenna 311 is located downstream of the heat generating unit 18L of the thermal head 18 in the transport path of the continuous paper CP and on the label printing side of the transported continuous paper CP. The reason why the RFID antenna 311 is located on the label printing side of the continuous paper CP is as follows. When attaching the label PL to a conductive material such as metal, a metal sheet may be provided on the adhesive layer side of the inlay IL to prevent the electromagnetic waves from being canceled out. In this case, the label PL is configured such that the inlay IL and the thermal layer are laminated in this order on the upper surface of the substrate, and the metal sheet (e.g., an aluminum sheet) and the adhesive layer are laminated in this order on the lower surface of the substrate. Therefore, the RFID antenna 311 is located on the label printing side of the continuous paper CP so that communication with the inlay IL via electromagnetic waves radiated from the RFID antenna 311 is possible.

[0062] Next, referring to FIG. 11 , a preferred method for connecting the RFID antenna 311 and the reader / writer 91 will be described. Similar to FIG. 2 , FIG. 11 is a side view of a portion of the printer 1 with the interior visible. The RFID antenna 311 and the reader / writer 91 are not actually visible from the side, but are shown visible for illustrative purposes. FIG. 11 shows a wiring path when connecting the RFID antenna 311 and the reader / writer 91 via a relay board. As described above, the RFID antenna 311 is disposed adjacent to the ribbon adjustment plate 66, and the reader / writer 91 is built into the label support mechanism 70. Therefore, the RFID antenna 311 and the reader / writer 91 must be electrically connected via wiring. While the RFID antenna 311 and the reader / writer 91 may be directly connected via a single wire, connecting them via a relay board improves operability. As shown in FIG. 11 , the relay board 24 is fixed to the support plate 171 of the print head unit 13. One end of the wiring 312 is connected to the RFID antenna 311, and a connector 312c attached to the other end is connected to a connector (not shown) of the relay board 24. One end of the wiring 912 is connected to the reader / writer 91, and a connector 912c attached to the other end is connected to a connector (not shown) of the relay board 24. A wiring that electrically connects the wiring 312 and the wiring 912 is mounted on the relay board 24. In this configuration, when connecting the RFID antenna 311 and the reader / writer 91, the connector 312c and the connector 912c on the relay board 24 are inserted into each other, which improves workability compared to when the RFID antenna 311 and the reader / writer 91 are connected with a single wiring.

[0063] Next, the electrical configuration of the printer 1 will be described with reference to the block diagram of Fig. 12. As shown in Fig. 12, the control unit 8 of the printer 1 includes a CPU 81, a ROM 82, a RAM 83, an input interface (I / F) 84, a display control unit 85, a motor controller 86, a head controller 87, a sensor interface (I / F) 88, a reader / writer interface (I / F) 89, and a communication bus 90. Although not shown, a control unit that constitutes the control unit 8 of the printer 1 is built into the printer 1.

[0064] The CPU 81 loads firmware stored in the ROM 82 into the RAM 83 and executes it to realize various functions of the printer 1. The firmware controls the transport of the continuous paper CP based on output signals from the label position detection sensor 74 and the label presence / absence detection sensor 64. The firmware also records data read by the reader / writer 91 from the inlay IL and transmits data to be written by the reader / writer 91 to the reader / writer interface 89 via the reader / writer interface 89. The input interface 84 is an interface that accepts operation inputs made via the input buttons 3 and transmits the inputs to the CPU 81. The display control unit 85 displays images on the display panel 4 based on display data received from the CPU 81. The motor controller 86 includes a drive circuit that drives the motor 9 based on control signals sent from the firmware. The control signals include, for example, information regarding the transport amount of the continuous paper CP. The head controller 87 includes an image buffer and, based on control signals (e.g., strobe signals) sent from the firmware, controls the flow of current selectively to multiple heating elements included in the heating unit 18L of the thermal head 18 in accordance with print data. The sensor interface 88 receives output signals from the label position detection sensor 74 and the label presence / absence detection sensor 64, converts them into digital values, and sends them to the CPU 81. The reader / writer interface 89 is an interface between the control unit 8 and the reader / writer 91, and sends instruction signals for reading and writing from the firmware to the reader / writer 91. The reader / writer interface 89 receives read data from the reader / writer 91 and sends data to be written to the inlay IL to the reader / writer 91.

[0065] Next, an example of a label transport method when the printer 1 issues labels PL will be described with reference to FIGS. 13 to 15. Each of FIGS. 13 to 15 shows the relative positions of the heat generating portion 18L of the print head (heating element position), the detection position of the label position detection sensor 74, and the RFID antenna 311 in various states along the timeline of the continuous paper (including the first label PL#1, the second label PL#2, and so on). As mentioned above, the RFID antenna 311 is positioned downstream of the heat generating portion 18L of the thermal head 18 in the transport path of the continuous paper CP. Therefore, when multiple labels PL are issued sequentially, the label transport method shown in any of FIGS. 13 to 15 can prevent the first label PL from being wasted.

[0066] (I) First Example of Label Conveying Method (FIG. 13) Referring to FIG. 13, in the first example, when printing labels on a continuous sheet of paper, the printer 1 waits with the print start position of the first label PL#1 positioned at the heating element position (state ST11). When printing each label, the printer 1 writes data to the inlay of each label before printing. In this state, the printer 1 receives print data from a host computer (not shown) and starts printing the label. First, the printer 1 conveys the first label PL#1 in the forward direction F (downstream) to a communication position where communication with the inlay IL of the first label PL#1 is performed via the RFID antenna 311 (state ST12). Because the distance between the heating element position and the reference position of the RFID antenna 311 (e.g., the center position of the RFID antenna 311 in the conveying direction) is known, the conveyance amount from state ST11 to state ST12 (referred to as the "optimal offset amount") is predetermined to optimize the reading and writing of data from and to the inlay IL. After writing data to the inlay IL of the first label PL#1 in state ST12, the continuous paper CP is transported in the reverse direction (upstream), and after the print start position of the first label PL#1 is positioned at the heating element position as in state ST11 (state ST13), printing is performed on the first label PL#1 (state ST14). The process for issuing each label from the second label PL#2 onwards is the same as for the first label. Note that when the print start position of each label is positioned at the heating element position, the label position detection sensor 74 detects the edge of each label, and the continuous paper CP is transported a predetermined amount according to the distance from the label position detection sensor 74 to the heating element position.

[0067] According to the first example of the label feeding method, when writing data to the inlay IL of the first label PL#1, the label is fed forward from the standby position (the position in state ST11), so it is possible to issue the first label PL#1 without it falling off from the heating element position. Therefore, the first label PL#1 is not wasted. In the first example of the label feeding method, printing is performed on the entire area of ​​the label PL from the print start position after communication with the inlay IL, so good print quality is obtained.

[0068] (II) Second Example of Label Conveying Method (FIG. 14) Referring to FIG. 14, in the second example, when printing labels on a continuous paper, the printer 1 causes the first label PL#1 to wait at the communication position (i.e., the position where the RFID antenna 311 and the inlay IL of the first label PL#1 communicate) (state ST21). When printing each label, the printer 1 writes data to the inlay of each label before printing. In state ST21, the printer 1 receives print data from a host computer (not shown) and starts printing labels. First, in state ST21, the printer 1 writes data to the inlay IL of the first label PL#1, then conveys the continuous paper CP in the reverse direction (upstream) until the print start position of the first label PL#1 is positioned at the heating element position (state ST22), and then prints the first label PL#1 while conveying it in the forward direction F (state ST23). The printer 1 then further transports the continuous paper CP in the forward direction F, causing the second label PL#2 to wait at the communication position. The issuance of each label from the second label PL#2 onwards is similar to the first label. When each label is positioned at the communication position, the label position detection sensor 74 detects the edge of each label, and the printer 1 transports the continuous paper CP a predetermined amount according to the distance from the position of the label position detection sensor 74 to the known communication position.

[0069] According to the second example of the label conveying method, there is no need to convey the first label PL#1 from the standby position when writing data to the inlay IL, and the continuous paper CP does not fall off from the heating element position even when conveyed in reverse for printing. Therefore, it is possible to issue the first label PL#1, and the first label PL#1 is not wasted. In the second example of the label conveying method, printing is performed on the entire area of ​​the label PL from the print start position after communication with the inlay IL, so good print quality is obtained.

[0070] (III) Third Example of Label Conveying Method (FIG. 15) Referring to FIG. 15, in the third example, when printing each label on a continuous paper, the printer 1 waits for the first label PL#1 with the print start position located at the heating element position, as in the first example (state ST31). In the third example, when printing each label, the printer 1 prints partway through, writes data to the inlay, and then prints the remaining part. That is, when printing the first label PL#1, the printer 1 prints partway through the first label PL#1 while transporting the continuous paper CP in the forward direction F (downstream) from state ST31. The printer 1 stops transport of the continuous paper CP when the first label PL#1 is in the communication position (state ST32) and writes data to the inlay IL of the first label PL#1. Next, the printer 1 prints the remaining part of the first label PL#1 while further transporting the continuous paper CP in the forward direction F (state ST33). The printing of the second label PL#2 and each subsequent label is similar to the first label. When the print start position for each label is positioned at the heating element position, the label position detection sensor 74 detects the edge of each label and feeds the continuous paper CP a predetermined amount according to the distance from the position of the label position detection sensor 74 to the heating element position. After printing of the first label PL#1 is completed, printing of the second label PL#2 may be started without stopping the feeding of the continuous paper CP.

[0071] According to the third example of the label conveying method, when writing data to the inlay IL of the first label PL#1, it is only necessary to convey the label PL forward from the standby position, so that the first label PL#1 can be issued without falling off from the heating element position. Therefore, the first label PL#1 is not wasted. In the third example of the label conveying method, there is no need to convey the label PL in the reverse direction after the reader / writer has communicated with the inlay IL, improving throughput. In the third example of the label conveying method, conveyance of the continuous paper CP may or may not be stopped in state ST32. Because the time required to write data to the inlay is short, data can be written to the inlay while conveying the continuous paper CP before and after the communication position. Stopping conveyance of the continuous paper CP in state ST32 has the advantage of allowing the reader / writer to stably communicate with the RFID inlay at the communication position.

[0072] As explained with reference to the first to third examples of the label conveying method, the control unit 8 controls the reader / writer 91 to communicate with the inlay IL of the label PL at the communication position where the label PL is conveyed by the above-mentioned optimum offset amount in the conveying direction from the print start position of the label PL. In each of the above examples of the label conveying method, the case where writing is performed on the inlay of the label is explained, but data may be read from the inlay of the label before or after the timing of writing.

[0073] As described above, in the printer 1 described above, the RFID antenna 311 is located downstream of the heating element 18L of the thermal head 18 in the transport path of the continuous paper CP. Therefore, when writing data to the inlay of the first label, the leading edge of the first label does not fall off from the heating element of the print head. In other words, because the RFID antenna 311 is located downstream of the heating element of the thermal head 18, there is no need to transport the continuous paper CP in the reverse direction when writing data to the inlay of the first label, and the first label is prevented from falling off from the heating element. Therefore, the first label can be printed without waste.

[0074] Although Fig. 10B shows an example in which the RFID antenna is disposed on the ribbon adjustment plate, the RFID antenna can be disposed in other locations. Below, modified examples of printer 1 in which the RFID antenna is disposed in a location different from the location shown in Fig. 10B will be described with reference to Figs. 16 to 21B.

[0075] (I) First Modification Figure 16 is a diagram showing an RFID antenna 311A ​​disposed in a head holding unit 36A in a printer according to a first modification. The head holding unit 36A differs from the head holding unit 36 ​​shown in Figure 6 in that a connecting member 365 is provided at the front end to connect the side walls 362 on both sides. In this modification, the RFID antenna 311A ​​is attached to the front surface of the connecting member 365. The RFID antenna may also be disposed on the rear surface of the connecting member 365.

[0076] 17 is a diagram showing an RFID antenna 311B disposed at the tip of the thermal head 18 in a printer according to a second modification. In this modification, the RFID antenna 311B is attached to the front surface of the heat sink 181 of the thermal head 18.

[0077] (III) Third Modification Figure 18A is a side view of a thermal head in a printer according to a third modification, showing an RFID antenna 311C disposed on the bottom surface of the thermal head. In this modification, the heat sink 181C of the thermal head extends forward compared to the heat sink 181 shown in Figure 7. That is, the front end surface 181Cf of the heat sink 181C is located forward of the front end surface 181f (shown in phantom lines) of the heat sink 181. The RFID antenna 311C is attached to the bottom surface of the heat sink 181C, forward of the heat-generating portion 18L.

[0078] (IV) Fourth Modification Figure 18B shows an RFID antenna 311D disposed in an opening 181h provided in a thermal head of a printer according to a fourth modification. The heat sink 181D of the thermal head of the printer according to this modification differs from the heat sink 181 shown in Figure 7 in that an opening 181h is formed in front of the heat generating portion 18L, and the RFID antenna 311D is disposed within the opening 181h.

[0079] (V) Fifth Modification FIG. 19A is a diagram showing an RFID antenna 311E disposed in a head attachment 38E in a printer according to a fifth modification. FIG. 19B is a side view of the front portion of the head attachment 38E when the head attachment 38E shown in FIG. 19A is mounted on a printer. In this modification, the head attachment 38E differs from the head attachment 38 shown in FIG. 7 in the position of the front end of the center plate. That is, the front end 381Ef of the center plate 381E of the head attachment 38E is located forward of the front end 381f (shown in phantom lines) of the center plate 381 of the head attachment 38E. The RFID antenna 311E is located near the front end 381Ef on the bottom surface of the center plate 381E. As shown in FIG. 19B, the RFID antenna 311E is located forward of the heat-generating portion 18L of the thermal head 18.

[0080] (VI) Sixth Modification Figure 20 shows an RFID antenna 311F placed near the label presence detection sensor 64 in a printer according to the sixth modification. The printer according to the sixth modification is provided with a member 64Ex that extends the housing for the label presence detection sensor 64 in the -X direction. An RFID antenna 311F is attached to the bottom surface of the member 64Ex (see the view along arrow B). The horizontal length of the member 64Ex is not important, as long as it is long enough to accommodate the RFID antenna 311F.

[0081] (VII) Seventh Modification FIG. 21A is a perspective view of a printer according to a seventh modification. FIG. 21B is a cross-sectional view of the printer of FIG. 21A near the paper outlet 5A, showing an RFID antenna located near the cutter 45 or downstream of the cutter 45. As shown in FIG. 21B, the printer according to the seventh modification differs from printer 1 in that the cutter 45 is located near the label outlet 5A. The cutter 45 has a fixed blade 451 fixed to the wall 25 of the printer housing and a movable blade 452 that can move up and down. At this time, the continuous paper CP passes through the transport opening 45S downstream of the thermal head 18 and is discharged from the paper outlet 5A. The paper outlet 5A is formed by an upper member 51 located above (on the printing surface side of) the continuous paper CP being transported and a lower member 52 located below the continuous paper CP being transported. In this modified printer, the RFID antenna 311G or the RFID antenna 311H may be disposed on the wall 25 adjacent to the fixed blade 451 (i.e., near the cutter 45). The RFID antenna 311G is disposed on the surface of the wall 25 facing the continuous paper CP. The RFID antenna 311H is disposed on the surface of the wall 25 facing the thermal head 18. In this modified printer, the RFID antenna 311J may be disposed on the upper member 51 downstream of the cutter 45.

[0082] In the printers according to any of the first to seventh modifications, the RFID antenna is located downstream of the transport path of the continuous paper CP relative to the heat generating portion 18L of the thermal head 18, and on the label printing side of the transported continuous paper CP. Therefore, in each modification, the effect of issuing the first label without waste is achieved, just as in the case where the RFID antenna is located on the ribbon adjustment plate.

[0083] The first modification has the advantage that the wireless antenna can be accurately positioned downstream of the heat generating portion of the print head. The second to fifth modifications have the advantage that the RFID antenna can be integrated with the thermal head 18, and the RFID antenna can be accurately positioned downstream of the heat generating portion 18L of the thermal head 18. The sixth and seventh modifications have the advantage that the RFID antenna is disposed separately from the thermal head 18, and therefore there is no need to remove the RFID antenna when replacing the thermal head 18.

[0084] Although the embodiment of the printer of the present invention has been described above, the present invention is not limited to the above embodiment. Furthermore, the above embodiment can be improved or modified in various ways without departing from the spirit of the present invention.

[0085] The present invention is related to patent application No. 2023-126132, filed with the Japan Patent Office on August 2, 2023, the entire contents of which are incorporated herein by reference.

Claims

1. A printer that prints on a print medium having an RFID inlay, comprising: a platen roller that transports the print medium; a print head that has a heating section consisting of multiple heating elements arranged in a line and prints on the print medium while pinching the print medium between the heating section and the platen roller; a wireless antenna that is downstream of the heating section of the print head on the transport path of the print medium and is located on the printing surface side of the print medium being transported; and a reader / writer that communicates with the RFID inlay on the print medium via the wireless antenna.

2. The printer according to claim 1, wherein the print head has a head body and a heat exhaust section attached to the head body, and the wireless antenna is attached to the heat exhaust section.

3. The printer according to claim 1, further comprising a head assembly including said print head, said wireless antenna being attached to said head assembly.

4. The printer according to claim 1, comprising: a head assembly including the print head; and a head holder that detachably holds the head assembly, the wireless antenna being attached to the head holder.

5. A printer as described in claim 1, wherein the print head prints on the print medium while sandwiching the print medium and ink ribbon between the heating section and the platen roller, the printer is provided with a ribbon adjustment section that adjusts the tension of the ink ribbon downstream of the transport path of the ink ribbon, and the wireless antenna is attached to the ribbon adjustment section.

6. A printer as claimed in any one of claims 1 to 5, further comprising a control unit that controls the reader / writer to communicate with an RFID inlay on the print medium at a communication position transported a predetermined distance in the transport direction from the print start position of the print medium.

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