Patent Publication Number: US-8537183-B2

Title: Printing device and data writing method thereof

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2010-192681, filed on Aug. 30, 2010, the entire contents of which are incorporated herein by reference. 
     FIELD 
     Embodiments described herein relate generally to a printing device and a data writing method thereof for a recording medium such as a wireless tag, the printing device performing printing on the recording medium and performing data writing on the wireless tag. 
     BACKGROUND 
     Recently, printing devices have complicated and various functions and purposes and are required to perform various types of printing functions or operations. For example, printing devices perform printing on a recording medium having a label attached on a backing sheet and also write data (transmitted from an antenna) on a wireless tag provided on the label. 
     In such a printing device, when the printing on the recording medium is performed concurrently with the data writing on the wireless tag provided on the recording medium, accurate data writing on the wireless tag may not be accomplished. This is due to an antenna for use in data writing on the wireless tag being placed at a fixed location, while the recording medium (including the wireless tag) is being conveyed during the printing process. This may make it difficult to maintain an appropriate distance between the wireless tag and the antenna. To accomplish accurate data writing on the wireless tag, a conveying mechanism may need to be halted during the process of data writing on the wireless tag. However, as a result, the entire processing time of the printing device may be prolonged. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exterior view showing an example of the exterior of a printing device according to one embodiment. 
         FIG. 2  is an interior view showing an example of the interior of the printing device. 
         FIG. 3  is a side view showing an example of the mechanical structure of the interior of the printing device. 
         FIG. 4  illustrates an example of the mechanical configuration of the printing device. 
         FIG. 5  is a block diagram showing an example of a functional configuration of the printing device. 
         FIG. 6  illustrates an example of a backing sheet with a wireless tag used in the printing device. 
         FIG. 7  is a flow chart showing an example of a process of writing data to the wireless tag in the printing device. 
     
    
    
     DETAILED DESCRIPTION 
     According to one embodiment, a printing device includes a printing unit configured to print on a recording medium including a wireless tag and a conveying unit configured to convey the recording medium to the printing unit along a conveying path. The printing device further includes an antenna unit configured to write data on the wireless tag by radiating an electromagnetic wave, a moving unit configured to move the antenna unit along the conveying path, and a control unit configured to control the moving unit to move the antenna unit so that the antenna unit is capable of writing data on the wireless tag, while the conveying unit is conveying the recording medium to the printing unit. 
     Some embodiments will now be described in detail with reference to the drawings. A printing device  1  according to an embodiment will be described referring to  FIGS. 1 to 5 . The printing device  1  according to the present embodiment includes a control unit  11  configured to control the entire operation, an operation unit  4  provided on the front side of the printing device  1  and configured to provide an operation signal to the control unit  11  in response to operation by a user, and a display unit  3 , e.g., employing an LCD (Liquid Crystal Display) or the like, configured to display operation information, an operation menu, etc. The display unit  3  may be provided, e.g., on the front side of the printing device  1 . The printing device  1  further includes a ROM (Read Only Memory)  12  and a RAM (Random Access Memory)  13  configured to store the operation information, setting information, and operating program, etc., a thermal head  14  configured to print on a recording medium such as a label under the control of the control unit  11 . Further, the printing device  1  includes a communication unit  15  configured to communicate with an external host computer H to which a user inputs an instruction for printing, information about the recording medium (e.g., values a, b and c, which will be described later in detail) and the like, and a label sensor  16  configured to detect a label  41  (which will be described later referring to  FIG. 6 ) by detecting a light transmittance of a backing sheet D using a light emitting unit  16 - 1  and a light receiving unit  16 - 2 , as shown in  FIG. 4 .  FIG. 4  is an enlarged view of a conveying path  31  for a wireless tag M, a linear antenna motor  35  (“linear motor”) provided to be parallel with the conveying path  31 , and a linear sensor  36  configured to detect the current position of a wireless tag antenna  34  (“antenna unit”). The label sensor  16  may be implemented with a sensor configured to detect the light transmittance of the backing sheet D. Alternatively, the label sensor  16  may be implemented using, for example, a reflection sensor configured to emit a light on a backing sheet D having a top surface with a label attached thereon and a bottom surface with black marks printed thereon, so that a position of the label  41  (see  FIG. 6 ) can be detected based on a light reflectivity difference between parts on which the black marks are printed and the parts on which the black marks are not printed. 
     The printing device  1  further includes an electromagnetic wave generating unit  30  (see  FIG. 5 ) configured to generate an electromagnetic wave used for writing data to the wireless tag M. Further, the printing device  1  includes the conveying path  31  along which a backing sheet D with a recording medium (e.g., a label) attached thereon is conveyed, and backing sheet conveying motors  32  and  33  configured to drive conveyance of the backing sheet D. The wireless tag antenna  34  is configured to receive the electromagnetic wave from the electromagnetic wave generating unit  30  and radiate the received electromagnetic wave for writing data onto the wireless tag M. The linear antenna motor  35  is configured to linearly move the wireless tag antenna  34 , and the linear sensor  36  is configured to detect the current position of the wireless tag antenna  34 . As shown in  FIGS. 2 and 3 , the printing device  1  further includes an ink ribbon supply shaft  55 , a ribbon take-up shaft  56 , a paper holding shaft  57 , and a pair of side fences  58   a  and  58   b.    
     With the above configuration, in response to a user&#39;s operation on the operation unit  4  or an instruction from the host computer H and under the control of the control unit  11 , the printing device  1  is operated to print, for example, price information, on a label attached on a backing sheet D with the thermal head  14  and to convey the backing sheet D by the backing sheet conveying motors  32  and  33 , so that a printed recording medium (i.e., the label) is provided to the outside of the printing device  1 . 
     Further, as an example of a printing paper for use in the printing device  1 , a plurality of the labels  41  may be attached on the backing sheet D, each label  41  having the wireless tag M attached thereon, as shown in  FIG. 6 . In this embodiment, information on the backing sheet D, for example, values a, b and c, respectively indicating a size of the label  41 , an attachment position of the wireless tag M, and a space between the labels, may be inputted, e.g., by means of the operation unit  4 , and stored in the control unit  11 , as will be described later. 
     In the present embodiment, the printing device  1  is operated to write data on the wireless tag M by the wireless tag antenna  34  (in addition to printing on the label  41 ). Alternatively, the printing device  1  may print only on the label  41  without the wireless tag M attached thereon and also may print on a simple recording medium such as a printing paper without the label  41  attached thereon. 
     In the following, a data writing process on a wireless tag M by the printing device  1  according to one embodiment will be described in detail referring to the flow chart in  FIG. 7 . The data writing process may be performed on the wireless tag M concurrently with the printing process on the label  41  with the wireless tag M attached thereon. In this case, the two processes are performed in parallel with each other or partially in parallel with each other, thereby reducing the entire processing time. In this embodiment, the data writing process on the wireless tag M on the label  41  is performed while moving the wireless tag antenna  34  along with the movement of the wireless tag M, so that the wireless tag antenna  34  and the wireless tag M are placed within a distance in which the wireless tag antenna  34  can write data on the wireless tag M. This data writing process is performed concurrently with the movement of the backing sheet D toward the thermal head  14  by the backing sheet conveying motors  32  and  33  in the printing process. 
     As described above, in the case of using a wireless tag antenna  34  fixed at a certain location, the backing sheet conveying motors  32  and  33  may be required to be paused in order to prevent the deterioration of data writing accuracy. However, according to the embodiment, the linear antenna motor  35  mounting the wireless tag antenna  34  thereon is configured to move substantially at the same speed as the conveying speed of the backing sheet conveying motors  32  and  33 . This configuration eliminates the need for decelerating the conveying speed of the backing sheet conveying motors  32  and  33  during the data writing process. 
     Specifically, as shown in the flow chart in  FIG. 7 , the control unit  11  detects whether the printing device  1  is powered on and initialized for a printing operation (Act A 11 ). When the initialization of the printing device  1  is detected (i.e., “YES” of Act A 11 ), the control unit  11  receives information on the backing sheet D, for example, the values a, b and c respectively indicating the size of the label  41 , the attachment position of the wireless tag M with respect to the label  41  and the space between the labels  41 , via the communication unit  15  from the external host computer H, and stores the received values a, b and c in a memory area such as the RAM  13  (Act A 12 ). Alternatively, the values a, b and c may be inputted from an operation panel of the operation unit  4 . 
     If the backing sheet conveying motors  32  and  33  are operated to drive conveyance of the backing sheet D (Act A 13 ), the control unit  11  determines a current position of a target wireless tag M, based on the pre-inputted values a, b and c, and a previous position and current conveying speed of the movement of the target wireless tag M. Further, the control unit  11  designates the current position of the current target wireless tag M as an optimum position of the wireless tag antenna  34 , which is to be moved by the linear antenna motor  35  along the conveying path  31  of the target wireless tag M (Act A 14 ). Based on the current position of the wireless tag antenna  34  detected by the linear sensor  36 , the control unit  11  controls the linear antenna motor  35  to move the wireless tag antenna  34  to reach the determined current position of the current target wireless tag M, so that the wireless tag antenna  34  can follow the current target wireless tag M moving along the conveying path  31  thereof substantially at the same speed (Act A 15 ). While the wireless tag antenna  34  is moving together with the target wireless tag M at the same speed, the wireless tag antenna  34  does not move substantially in relation with the target wireless tag M (i.e., there is no relative movement therebetween). The data writing process is done simultaneously as the printing on the label  41  provided on the backing sheet D is being performed (Act A 16 ). 
     In the above operations, the position of the wireless tag antenna  34  does not necessarily need to completely correspond to the determined current position of the wireless tag M. In other words, the wireless tag antenna  34  may be slightly apart from the wireless tag M as long as they are close to each other enough to reliably write data to the wireless tag M (e.g., within a communication range of the antenna). 
     In this embodiment, while the wireless tag antenna  34  is moving to follow the target wireless tag M, the backing sheet conveying motors  32  and  33  can continue conveying the wireless tag M to the thermal head  14  without slowing down the moving speed of the wireless tag M. However, if the time required for writing on the wireless tag M is longer than the time required for moving the label  41  with the wireless tag M attached thereon to the thermal head  14  by the backing sheet conveying motors  32  and  33 , the moving speed of the backing sheet conveying motors  32  and  33  may need to be decreased together with the moving speed of the linear antenna motor  35  during the data writing process, to thereby secure enough time for completion of data writing. Further, once the data writing on the wireless tag M is completed, the moving speed of the wireless tag M may be accelerated. 
     Proper moving speeds of the wireless tag M and the wireless tag antenna  34  may be determined through experiments of performing the data writing while moving the wireless tag M and the wireless tag antenna  34  at various speeds. For example, the speed of printing on the backing sheet D may be set within the range from 10 IPS (Inch Per Second) to 14 IPS. In one experiment, it was shown that while the backing sheet D and the wireless tag M are moving at the above speed, it is possible to write data on the wireless tag M by moving the wireless tag antenna  34  along the wireless tag M at the same speed. 
     As described above, in this embodiment, since the backing sheet conveying mechanism continues to operate without any interruption during the data writing process on the wireless tag M, the overall processing speed may not be deteriorated due to the data writing process. As such, the present embodiment provides a printing device and the data writing method thereof, enabling expeditious printing and data writing. 
     After completion of the data writing process as described above, the backing sheet D arrives at the thermal head  14  and the printing process is performed on the label  41  by the thermal head  14 . Then, the label  41  is cut by a cutter (not illustrated) together with the backing sheet D and provided to the outside of the printing device  1 . 
     Alternatively, the data writing process on the wireless tag M may be performed concurrently with the printing process on the label  41  by the thermal head  14 , after the backing sheet D arrives at the thermal head  14 . 
     As used in this application, entities for executing the operations can refer to a computer-related entity, either hardware, a combination of hardware and software, software, or software in execution. For example, an entity for executing an operation can be, but is not limited to being, a process running on a processor, a processor, an object, an executable, a thread of execution, a program, and a computer. By way of illustration, both an application running on an apparatus and the apparatus can be an entity. One or more entities can reside within a process and/or thread of execution and an entity can be localized on one apparatus and/or distributed between two or more apparatuses. 
     The program for realizing the functions can be recorded in the apparatus, can be downloaded through a network to the apparatus or can be installed in the apparatus from a computer readable storage medium storing the program therein. A form of the computer readable storage medium can be any form as long as the computer readable storage medium can store programs and is readable by the apparatus such as a disk type ROM and a solid-state computer storage media. The functions obtained by installation or download in advance in this way can be realized in cooperation with an OS (Operating System) in the apparatus. 
     While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.