Wireless tag communication device and sheet handling device

Abstract

A wireless tag communication device and a sheet processing device are provided. The wireless tag communication device has a radiating element and a radiation control section. The radiating element is a conductor and has a first radiation region having a long axis with a first length in a direction perpendicular to a reference direction, the reference direction being at a predetermined angle to a conveying direction of a wireless tag; a second radiation region having a long axis with a second length in a direction perpendicular to the reference direction; a third radiation region having a long axis with a third length in a direction parallel to the reference direction; and a fourth radiation region having a long axis with a fourth length in a direction parallel to the reference direction. The radiation control section causes the radiating element to radiate polarized waves from at least one of the first radiation region to the fourth radiation region. The first radiation region and the second radiation region share a portion with the third radiation region or the fourth radiation region, and the third radiation region and the fourth radiation region share a portion with the first radiation region or the second radiation region.

Description

Technical Field

[0001] Embodiments of the present invention relate to a wireless tag communication device and a sheet processing device. Background Technology

[0002] An image forming apparatus is known to form an image on a sheet of material to which wireless tags such as RFID (radio frequency identifiers) are attached. This image forming apparatus has an antenna capable of transmitting and receiving radio waves, and there are instances where information is exchanged between the wireless tags on the sheet and the radio waves. Therefore, the antenna in this image forming apparatus radiates radio waves that the wireless tags can receive. Specifically, the radio waves that the wireless tags can receive are those whose polarization plane is the same as that of the wireless tags and whose frequency corresponds to the frequency band that the wireless tags can receive.

[0003] However, there are various types of wireless tags on the sheet. For example, the frequency bands that wireless tags can receive vary from country to country. In such cases, in an image forming apparatus that can only radiate radio waves in the frequency band corresponding to a specific country, there may be situations where the type of wireless tag cannot be matched. This difference in the types of wireless tags that can be used depends not only on the country, but also on the environment in which the image forming apparatus is used, such as the region. Furthermore, this technical problem is not limited to image forming apparatuses, but is a common technical problem for apparatuses that process sheet materials. Summary of the Invention

[0004] The technical problem that the invention aims to solve

[0005] The technical problem to be solved by the present invention is to provide a wireless tag communication device and a sheet processing device that can reduce the situation where information cannot be exchanged with wireless tags due to different types of wireless tags.

[0006] Solutions for solving technical problems

[0007] The wireless tag communication device of the embodiment includes a radiating element and a radiation control unit. The radiating element is a conductor and has: a first radiating region having a major axis in a direction perpendicular to a reference direction and a minor axis in a direction parallel to the reference direction, the length of the major axis being a first length, the reference direction being at a predetermined angle to the transport direction of the wireless tag; a second radiating region having a major axis in a direction perpendicular to the reference direction and a minor axis in a direction parallel to the reference direction, the length of the major axis being a second length; a third radiating region having a major axis in a direction parallel to the reference direction and a minor axis in a direction perpendicular to the reference direction, the length of the major axis being a third length; and a fourth radiating region having a major axis in a direction parallel to the reference direction and a minor axis in a direction perpendicular to the reference direction, the length of the major axis being a fourth length. The radiation control unit causes the radiating element to radiate polarized waves from at least one of the first, second, third, and fourth radiating regions. The first radiation region and the second radiation region share a portion with the third radiation region or the fourth radiation region. The wireless tag is capable of receiving polarized waves radiated from the first radiation region, the second radiation region, the third radiation region, and the fourth radiation region.

[0008] The sheet processing apparatus of this embodiment includes a conveying component for conveying a sheet and a wireless tag communication device. The wireless tag communication device includes a radiating element and a radiation control unit. The radiating element is a conductor and has: a first radiating region having a major axis in a direction perpendicular to a reference direction and a minor axis in a direction parallel to the reference direction, the length of the major axis being a first length; the reference direction forming a predetermined angle with the conveying direction of the wireless tag; a second radiating region having a major axis in a direction perpendicular to the reference direction and a minor axis in a direction parallel to the reference direction, the length of the major axis being a second length; a third radiating region having a major axis in a direction parallel to the reference direction and a minor axis in a direction perpendicular to the reference direction, the length of the major axis being a third length; and a fourth radiating region. The radiation control unit causes the radiation element to radiate polarized waves from at least one of the first radiation region, the second radiation region, the third radiation region, and the fourth radiation region. The first radiation region and the second radiation region share a portion with the third radiation region or the fourth radiation region. The wireless tag is capable of receiving polarized waves radiated from the first radiation region, the second radiation region, the third radiation region, and the fourth radiation region. Attached Figure Description

[0009] Figure 1 This is a diagram illustrating an example of the image forming apparatus 10 according to an embodiment.

[0010] Figure 2 This is a functional block diagram of the image forming apparatus according to the embodiment.

[0011] Figure 3 This is a diagram illustrating an example of the location where a sheet may be present in the image forming apparatus of an embodiment.

[0012] Figure 4 This is a diagram illustrating an example of the relationship between the configuration of wireless tags on the sheet and the conveying direction of the sheet in an embodiment.

[0013] Figure 5 This is a diagram illustrating an example of the configuration of the wireless tag communication device 201 in the embodiment.

[0014] Figure 6 This is a side view of an example of the configuration of the antenna 600 according to an embodiment.

[0015] Figure 7This is an explanatory diagram illustrating an example of the shape of the radiating element in the embodiment.

[0016] Figure 8 This is a top view showing an example of the radiating element 630 of the embodiment.

[0017] Figure 9 The first figure shows an example of experimental results for measuring the frequency response characteristics of the wireless tag communication device 201 in relation to the radio waves transmitted and received by the wireless tag communication device 201 in the embodiment.

[0018] Figure 10 The second figure shows an example of experimental results for measuring the frequency response characteristics of the wireless tag communication device 201 in relation to the radio waves transmitted and received by the wireless tag communication device 201 in the embodiment.

[0019] Figure 11 This is a diagram illustrating an example of the experimental results of a comparative experiment.

[0020] Explanation of reference numerals in the attached figures

[0021] 10…Image forming apparatus; 100…Control unit; 201…Wireless tag communication device; 501…Wireless tag communication control unit; 502…Transceiver circuit unit; 503…Interface unit; 504…Modulation unit; 505…Transmitting amplifier; 506…Receiving amplifier; 507…Demodulation unit; 508…Circulator; 509…Switch; 600…Antenna; 610…Ground conductor plate; 620…Dielectric substrate; 630…Radiating element; 640, 641, 642…Power supply line. Detailed Implementation

[0022] Hereinafter, the wireless tag communication device and the sheet processing device according to embodiments will be described with reference to the accompanying drawings.

[0023] Furthermore, in the following description, components with the same or similar functions are marked with the same reference numerals. Additionally, there are cases where descriptions of repeated components are omitted.

[0024] Figure 1 This is a diagram illustrating an example of an image forming apparatus 10 according to an embodiment. The image forming apparatus 10 is an example of a sheet processing apparatus.

[0025] exist Figure 1 In this device, the image forming apparatus 10 includes a control panel 13, a wireless tag communication device 201, and a printing unit 18. The printing unit 18 includes a control unit 100, paper feed trays 161 and 162, etc. The control unit 100 controls the control panel 13, the wireless tag communication device 201, and the printing unit 18. The control unit 100 also controls the feeding of the sheet material in the printing unit 18. Controlling the feeding of the sheet material refers to controlling the feeding timing, the stopping position, and the feeding speed of the sheet material.

[0026] The control panel 13 includes input keys and a display unit. For example, the input keys accept user input. For example, the display unit is a touch panel. The display unit accepts user input and displays information to the user. For example, the control panel 13 displays items related to the operation of the image forming apparatus 10 in a configurable manner on the display unit. The control panel 13 notifies the control unit 100 of items set by the user.

[0027] Paper trays 161 and 162 accommodate sheets with wireless tags attached. Furthermore, paper trays 161 and 162 can obviously also accommodate sheets without wireless tags. In the following description, unless otherwise specified, the sheet is referred to as a sheet with a wireless tag. The sheet is made of raw materials such as paper or plastic film.

[0028] The printing unit 18 performs an image forming operation. For example, the printing unit 18 forms an image represented by image data on a sheet. In the following description, forming an image on a sheet also refers to printing. The printing unit 18 includes an intermediate transfer belt 21. The printing unit 18 supports the intermediate transfer belt 21 with a driven roller 41 and a support roller 40, etc. The printing unit 18 rotates the intermediate transfer belt 21 in the direction of arrow m.

[0029] The printing unit 18 has four image forming stations 221, 222, 223, and 224. Each image forming station 221, 222, 223, and 224 is configured for forming images of Y (yellow), M (magenta), C (cyan), and K (black), respectively. The image forming stations 221, 222, 223, and 224 are arranged below the intermediate transfer belt 21 along the rotation direction of the intermediate transfer belt 21.

[0030] The following description uses image forming station 221 (yellow) from image forming stations 221, 222, 223, and 224 as an example. Furthermore, image forming stations 222, 223, and 224 have the same configuration as image forming station 221, so detailed descriptions are omitted.

[0031] Image forming station 221 includes a charged charger 26, an exposure scanning head 27, a developing unit 28, and a photosensitive eraser 29. The charged charger 26, the exposure scanning head 27, the developing unit 28, and the photosensitive eraser 29 are arranged around the photosensitive drum 24, which rotates in the direction of arrow n.

[0032] Image forming station 221 includes a primary transfer roller 30. The primary transfer roller 30 is opposite to the photosensitive drum 24 across the intermediate transfer belt 21.

[0033] After the image forming station 221 charges the photosensitive drum 24 using the charged charger 26, it exposes it through the exposure scanning head 27. The image forming station 221 forms an electrostatic latent image on the photosensitive drum 24. The developing apparatus 28 develops the electrostatic latent image on the photosensitive drum 24 using a two-component developer formed from toner and carrier.

[0034] The primary transfer roller 30 transfers the toner image formed on the photosensitive drum 24 to the intermediate transfer belt 21 in one pass. Image forming stations 221, 222, 223, and 224 form color toner images on the intermediate transfer belt 21 via the primary transfer roller 30. For the color toner images, the toner images of Y (yellow), M (magenta), C (cyan), and K (black) are sequentially overlapped. The photoreceptor remover 29 removes any remaining toner from the photosensitive drum 24 after the primary transfer.

[0035] The printing unit 18 includes a secondary transfer roller 32. The secondary transfer roller 32 faces the support roller 40 across the intermediate transfer belt 21. The secondary transfer roller 32 performs a secondary transfer on the sheet, simultaneously transferring the color toner image from the intermediate transfer belt 21 onto the sheet. Furthermore, in the following description, "toner image" can refer to either a color toner image or a monochrome toner image. The toner image can also be a toner image using an achromatic toner.

[0036] Conveyor path 331 is the conveyor path from the confluence section 441 to the branch section 442. Conveyor path 332 is the conveyor path through the double-sided printing device 38, and is the conveyor path from the branch section 442 to the confluence section 441. Conveyor path 333 is the conveyor path from the branch section 442 to the paper discharge tray 20.

[0037] The leading edge of the sheet taken from the paper tray 161, paper tray 162, or manual tray 163 abuts against the portion of the two stopped alignment rollers 31. The sheet abutting against the alignment rollers 31 corrects the tilt of the sheet. The control unit 100 starts rotating the alignment rollers 31 in accordance with the position of the toner image on the rotating intermediate transfer belt 21, moving the sheet to the position of the secondary transfer roller 32. The control unit 100 transfers the toner image formed on the intermediate transfer belt 21 onto the sheet a second time via the secondary transfer roller 32. The control unit 100 conveys the sheet to the transport path 331 and forms an image by fixing the toner image onto the sheet using the fixing device 34. The control unit 100 discharges the sheet by conveying the sheet with the formed image to the transport path 333.

[0038] In the case of double-sided printing, the control unit 100 transports the sheet with the image formed on its surface to the transport path 333. After the sheet has passed the branch section 442, the control unit 100 turns it and transports the sheet to the transport path 332. Then, the control unit 100 transports the sheet to the confluence section 441 via the transport path within the double-sided printing apparatus 38, and then to the transport path 331 via the registration roller 331. Furthermore, the control unit 100 forms an image on the back side of the sheet using the fixing toner image fixed by the fixing device 34. The control unit 100 discharges the sheet by transporting the sheet with the image formed on the back side to the transport path 333.

[0039] The wireless tag communication device 201 can communicate with the control unit 100. The wireless tag communication device 201 reads information from and writes information to the wireless tag on the sheet by communicating with it. The wireless tag communication device 201 transmits signals in the direction of arrow k. Specifically, the signal is a modulated radio wave. Information is written to the wireless tag on the sheet through the signals transmitted by the wireless tag communication device 201.

[0040] Before the image formed in the printing unit 18 is transferred a second time in the secondary transfer roller 32, an electrostatic latent image is formed on the photosensitive drum 24 by the exposure scanning head 27. The electrostatic latent image formed on the photosensitive drum 24 is transferred as a toner image to the intermediate transfer belt 21. Moreover, the toner image transferred to the intermediate transfer belt 21 is transferred a second time to the wireless tag sheet that is being transported to the position of the registration roller 31.

[0041] Next, use Figure 2 A functional block diagram illustrating the image forming apparatus of the embodiments.

[0042] exist Figure 2 In this device, the image forming apparatus 10 includes a control unit 100, a control panel 13, a printing unit 18, and a wireless tag communication device 201.

[0043] The control unit 100 includes a computing device 51 and a storage device 52. The computing device 51 controls the control panel 13, the printing unit 18, and the wireless tag communication device 201 according to the image processing program stored in the storage device 52. The control unit 100 outputs information such as indicating the start of sheet feeding (hereinafter referred to as "feeding start information").

[0044] The arithmetic unit 51 is, for example, a CPU (Central Processing Unit) or an ASIC (Application Specific Integrated Circuit). The storage device 52 is, for example, ROM (Read-Only Memory), RAM (Random Access Memory), HDD (Hard Disk Drive), or SSD (Solid State Drive). The data receiving unit 53 receives printing data (e.g., data described by a page description language) representing a printed image from a host computer such as a PC (Personal Computer) and stores the received printing data in the storage device 52. The image data unfolding unit 54 determines printing conditions, etc., based on the printing data stored in the storage device 52 by the data receiving unit 53, thereby unfolding the data into data (e.g., raster data) that the printing unit 18 can print and storing it in the storage device 52.

[0045] The printing unit 18 includes a fixing device 34, a secondary transfer roller 32, and a developing device 28. The printing unit 18 forms an image on the sheet based on data stored in the storage device 52 via the image data unfolding unit 54.

[0046] Figure 3 This diagram illustrates an example of the possible locations where a sheet may be present in the image forming apparatus 10 according to an embodiment. Figure 3 In this context, sheet Sb represents the sheet placed in the paper feed cassette 161. Sheet Sc represents the sheet placed in the paper discharge tray 20. Sheet Sd represents the sheet placed in the manual tray 163. The aforementioned paper feed cassettes 161 and 162, paper discharge tray 20, and manual tray 163 are examples of the mounting section.

[0047] Sheet Sa represents the sheet being transported along conveyor path 331. Each sheet is equipped with a wireless tag.

[0048] exist Figure 3 In this context, the sheet that becomes the object to which information is written to the wireless tag (hereinafter also referred to as the "object sheet") is the sheet being transported in transport path 331. Therefore, sheet Sa is an example of an object sheet.

[0049] exist Figure 3 In the state shown, the wireless tag communication device 201 transmits a signal in the direction of arrow k. That is, direction k is the transmission direction of the signal transmitted by the wireless tag communication device 201. Therefore, direction k can also be the transmission direction of the radio waves radiated by the wireless tag communication device 201.

[0050] Each wireless tag that receives a signal performs an action corresponding to the content of the received signal. The wireless tag stores, for example, the information represented by the received signal. The wireless tag responds, for example, to the wireless tag communication device 201. Specifically, a response refers to transmitting a signal. The wireless tag communication device 201 receives signals transmitted from the wireless tags disposed on each sheet. Figure 3 In this case, one of the wireless tags receiving the signal is a wireless tag installed on the sheet Sa. Figure 3 In the process, sheet Sa is conveyed.

[0051] In a wireless tag, the shape within the plane perpendicular to the k-direction has both a major axis and a minor axis. When the wavelength of the radio waves is the same, polarized waves with their polarization plane parallel to the major axis interact more strongly than those with their polarization plane perpendicular to the major axis. Stronger interaction means that the probability of the radio wave passing through the wireless tag is lower, and the probability of the radio wave reaching the wireless tag being absorbed or reflected by the tag is higher. Therefore, using radio waves with their polarization plane parallel to the major axis of the wireless tag for information exchange with the wireless tag is preferable from the viewpoint of reducing power consumption and the frequency of communication errors. Furthermore, a communication error means that information exchange between the wireless tag communication device 201 and the wireless tag cannot occur.

[0052] Figure 4 This is a diagram illustrating an example of the relationship between the arrangement of wireless tags on the sheet and the conveying direction of the sheet in an embodiment. Figure 4 Tag Ta, Tag Tb, Tag Tc, and Tag Td are examples of wireless tags set on sheet Sa during transport along conveyor path 331. Tag Ta is an example of a wireless tag set on sheet Sa with its major axis perpendicular to the transport direction and perpendicular to the major axis of the paper surface. Tag Tb is an example of a wireless tag set on sheet Sa with its major axis parallel to the transport direction and parallel to the major axis of sheet Sa. Tag Tc is an example of a wireless tag set on sheet Sa with its major axis perpendicular to the transport direction and parallel to the major axis of sheet Sa. Tag Td is an example of a wireless tag set on sheet Sa with its major axis parallel to the transport direction and perpendicular to the major axis of sheet Sa. Furthermore, in... Figure 4 The image shows an example of a single wireless tag configured on a sheet, but it is not necessary to configure only one wireless tag on a sheet; multiple wireless tags can also be configured on a single sheet.

[0053] In addition, the conveying direction of the sheet is, for example, in Figure 3 The direction perpendicular to the k direction and in Figure 3 The paper is transported from bottom to top. Furthermore, the wireless tags are mounted on the sheet, therefore the sheet's transport direction is also the wireless tag's transport direction.

[0054] Figure 5 This is a diagram illustrating an example of the configuration of the wireless tag communication device 201 in the embodiment.

[0055] The wireless tag communication device 201 includes an antenna 600, a wireless tag communication control unit 501, a transceiver circuit unit 502, and an interface unit 503.

[0056] Antenna 600 transmits signals. Antenna 600 receives signals. The carrier of the signals transmitted by antenna 600 is radio waves. The carrier of the signals received by antenna 600 is radio waves.

[0057] The wireless tag communication control unit 501 is configured to use a processor 901 such as a CPU and a memory 902. The wireless tag communication control unit 501 reads the program stored in the memory 902 from the processor 901 and operates by executing the read program. The wireless tag communication control unit 501 controls the operation of each functional unit of the wireless tag communication device 201. A write threshold is pre-stored in the memory 902.

[0058] The wireless tag communication control unit 501, for example, receives sheet transport start information. The wireless tag communication control unit 501, for example, transmits signals to the wireless tag communication device 201 by controlling the operation of each functional unit included in the wireless tag communication device 201. The wireless tag communication control unit 501, for example, demodulates the signals received by the antenna 600 by controlling the operation of each functional unit included in the wireless tag communication device 201. The wireless tag communication control unit 501, for example, measures the time elapsed after receiving the transport start information.

[0059] The transceiver circuit section 502 includes a modulation section 504, a transmitting amplifier 505, a receiving amplifier 506, a demodulation section 507, a circulator 508, and a switching switch 509.

[0060] The modulation unit 504 modulates the radio waves radiated by the wireless tag communication device 201. More specifically, a voltage modulated by the wireless tag communication control unit 501 is applied to the modulation unit 504, and due to the application of the voltage, the modulation unit 504 generates a modulated current. After the current generated by the modulation unit 504 flows to the transmitting amplifier 505, it generates radio waves through the antenna 600. The radio waves generated by the antenna 600 are the radio waves radiated by the wireless tag communication device 201. Therefore, the radio waves modulated by the modulation unit 504 are radio waves radiated by the antenna 600, and thus the radio waves modulated by the modulation unit 504 are the signals transmitted by the wireless tag communication device 201.

[0061] Transmitter amplifier 505 controls the strength of the signal transmitted by wireless tag communication device 201. Circulator 508 separates the signal transmitted by antenna 600 from the signal received by antenna 600.

[0062] The switching switch 509 switches the target of voltage application (i.e., the object through which the current modulated by the modulation unit 504 and amplified by the transmitting amplifier 505 flows). Specifically, the switching switch 509 switches the connection target of the transmitting amplifier 505 to one of the power supply lines 641 or 642, described later. The switching switch 509 is, for example, an RF (radio frequency) switch such as a single-pole double-throw switch. The operation of the switching switch 509 is controlled by the wireless tag communication control unit 501. By controlling the switching switch 509 to operate under the control of the wireless tag communication control unit 501, the target of voltage application is switched.

[0063] The receiving amplifier 506 controls the strength of the signal received by the antenna 600 to a predetermined strength. The demodulation unit 507 demodulates the signal received by the antenna 600.

[0064] Interface 503 is an interface that electrically connects wireless tag communication control unit 501 and control unit 100.

[0065] Figure 6 This is a side view illustrating an example of the configuration of the antenna 600 according to an embodiment. The antenna 600 is a microstrip antenna comprising a ground conductor plate 610, a dielectric substrate 620, and a radiating element 630. The ground conductor plate 610 is a grounded conductor. The dielectric substrate 620 is a dielectric material in contact with the ground conductor plate 610.

[0066] The radiating element 630 is a conductor located on the opposite side of the ground conductor plate 610, separated from the dielectric substrate 620, and is in contact with the dielectric substrate 620. The radiating element 630 is connected to power supply lines 641 and 642 that pass through the dielectric substrate 620 and the ground conductor plate 610. Power supply lines 641 and 642 are wires. When a voltage is applied to the radiating element 630 via either power supply line 641 or 642, it radiates an electromagnetic wave generated by the current produced by the applied voltage. The radiated electromagnetic wave is a signal. The wave vector of the electromagnetic wave radiated by the radiating element 630 is a vector pointing towards the k-direction. Hereinafter, without distinguishing between power supply line 641 and power supply line 642, it will be referred to as power supply line 640. The end of power supply line 640 that is not in contact with the radiating element 630 is connected to the switching switch 509.

[0067] For simplicity, the plane perpendicular to the k-direction will be referred to as the XY plane. From this, the vector perpendicular to the conveying direction of the sheet conveyed along conveying path 331 among the two mutually orthogonal vectors of the unfolded XY plane will be called the X vector, and the vector perpendicular to the X vector will be called the Y vector.

[0068] The shape of the surface of the radiating element 630 perpendicular to the k-direction is approximately the same regardless of the position of the k-direction. The length of the radiating element 630 in the k-direction is preferably shorter than the wavelength of the electromagnetic wave radiated by the radiating element 630, and is particularly preferably less than 1 / 4 of the wavelength.

[0069] Figure 7 This is an explanatory diagram illustrating an example of the shape (hereinafter referred to as "radiation element shape") in the XY plane of the radiating element 630 in the embodiment. Figure 7 The direction perpendicular to the paper is parallel to the k direction.

[0070] The surface surrounding the shape of the radiating element (hereinafter referred to as the "radiating element surface") has a first radiating region, a second radiating region, a third radiating region, and a fourth radiating region. That is, the first, second, third, and fourth radiating regions are located within the same surface. The first and second radiating regions are regions whose shape satisfies the condition that the length in the direction of the X vector is longer than the length in the direction of the Y vector. The third and fourth radiating regions are regions whose shape satisfies the condition that the length in the direction of the Y vector is longer than the length in the direction of the X vector.

[0071] exist Figure 7 In the diagram, the first radiation region is region 701, the second radiation region is region 702, the third radiation region is region 703, and the fourth radiation region is region 704.

[0072] The first and second radiation regions refer to areas where the lengths of the X-vector directions differ and they do not touch or overlap. The first radiation region shares a portion with either the third or fourth radiation region. The second radiation region shares a portion with either the third or fourth radiation region.

[0073] The third and fourth radiation regions refer to areas where the lengths of the Y-vector directions differ and they do not touch or overlap. The third radiation region shares a portion with either the first or second radiation region. The fourth radiation region shares a portion with either the first or second radiation region.

[0074] Figure 8 This is a top view showing an example of the radiating element 630 of the embodiment. Figure 8 The direction perpendicular to the paper is parallel to the k-direction.

[0075] Figure 8 Region 711 is an example of the first radiation region. Figure 8 Region 712 is an example of the second radiation region. Figure 8 Region 721 is an example of the third radiation region. Figure 8 Region 722 is an example of the fourth radiation region.

[0076] Figure 8In this design, the radiating element surface only needs to include a first radiating region, a second radiating region, a third radiating region, and a fourth radiating region. Alternatively, it can include either a first type of additional region or a second type of additional region in addition to the first, second, third, and fourth radiating regions. That is, the first, second, third, and fourth radiating regions, the first type of additional region, and the second type of additional region are located on the same surface.

[0077] The first type of additional region is a region with a shape that satisfies the condition that the length of the X-vector direction is longer than the length of the Y-vector direction, and is different from the first and second radiation regions. The first type of additional region is a region that does not contact or overlap with any other first type of additional region. The first type of additional region shares a portion with the third, fourth, or second type of additional region.

[0078] The second type of additional region is a region with a shape that satisfies the condition that the length of the Y-vector direction is longer than the length of the X-vector direction, and is different from the third and fourth radiation regions. The second type of additional region is a region that does not contact or overlap with any other second type of additional region. The second type of additional region shares a portion with the first, second, or first type of additional region.

[0079] Figure 8 Region 713 is an example of the first type of additional region. Figure 8 Region 723 is an example of the second type of additional region. The number of the first type of additional regions within the radiating element plane is not necessarily one; it can be two or more. Similarly, the number of the second type of additional regions within the radiating element plane is not necessarily one; it can be two or more.

[0080] Figure 8 Power supply points 731 and 732 are both power supply points. More specifically, power supply point 731 is the position where power supply line 641 and radiating element 630 come into contact (power supply point), and power supply point 732 is the position where power supply line 642 and radiating element 630 come into contact (power supply point).

[0081] Figure 9 as well as Figure 10 This is a figure illustrating an example of experimental results showing the frequency response characteristics of the wireless tag communication device 201 measured from the radio waves transmitted and received by the wireless tag communication device 201 according to an embodiment. More specifically, Figure 9 as well as Figure 10 It shows that for those with Figure 8The figure shows an example of experimental results for measuring the frequency response characteristics of a wireless tag communication device 201 by measuring the radio waves transmitted and received by the radiating element 630. In particular... Figure 10 The experimental results are presented using a Smith chart. The values ​​of the S-parameters were determined as part of the frequency response characteristics.

[0082] In the experiment, the raw material for the radiating element 630 was copper. Therefore, its conductivity was 5.8 × 10⁻⁶. 7 (S / m). In the experiment, the lengths of the X-vector directions of regions 711, 712, and 713 are 77mm, 72mm, and 67mm, respectively, and the lengths of the Y-vector directions of regions 711, 712, and 713 are 10mm, 21mm, and 20mm, respectively. In the experiment, the lengths of the X-vector directions of regions 721, 722, and 723 are 10mm, 21mm, and 20mm, respectively, and the lengths of the Y-vector directions of regions 721, 722, and 723 are 67mm, 72mm, and 77mm, respectively.

[0083] In the experiment, the dielectric substrate 620 was made of FR4 (Flame Retardant Type 4) with a dielectric constant of 4.6. Its length in the k-direction was 1.53 mm. Furthermore, the combined length in the k-direction of the ground conductor plate 610 and the radiating element 630 was 0.07 mm. In the experiment, the length of the X-vector direction of the surface of the dielectric substrate 620 in contact with the radiating element 630 was 130 mm, and the length of the Y-vector direction was also 130 mm.

[0084] In the experiment, the raw material for the conductor plate 610 was copper. Therefore, its conductivity was 5.8 × 10⁻⁶. 7 (S / m). In the experiment, the length of the ground conductor plate 610 in the k direction is 0.035 mm. In the experiment, the length of the X vector direction of the surface of the ground conductor plate 610 in contact with the dielectric substrate 620 is 130 mm, and the length of the Y vector direction is 130 mm.

[0085] Figure 9 as well as Figure 10 The S-parameter S11 is shown to be below (-10dB), which is a range of approximately 42MHz centered at 920MHz.

[0086] Next, use Figure 11 Explanation for use with Figure 9 as well as Figure 10 The results of the comparative experiment (hereinafter referred to as the "comparative experiment") were compared with those of the previous experiment. In the comparative experiment, a square patch antenna was used instead of antenna 600. The square patch antenna used in the comparative experiment was only different in that its shape in the XY plane of the conductor radiating the radio wave was square. Figure 8 The shapes shown are different in this respect. The square patch antenna used in the comparative experiment has a side length of 75 mm in the XY plane.

[0087] Figure 11 This is a diagram illustrating an example of the experimental results of a comparative experiment. Figure 11 The S-parameter S11 is shown to be below (-10dB), which is a range of approximately 10MHz centered at 920MHz.

[0088] Figure 9 , Figure 10 as well as Figure 11 This shows that antenna 600 is a wider bandwidth antenna compared to a square patch antenna.

[0089] Here, we will explain why antenna 600 has a wider bandwidth compared to a square patch antenna. For simplicity, the term "radiating region" will be used hereafter without distinguishing between the first, second, third, fourth, first, and second additional radiating regions. The portion of the radiating element 630 whose surface is part of the radiating region (hereinafter referred to as "radiating portion") has a shape where the length of one predetermined axis is longer than the length of the other orthogonal axes, as described above. That is, the radiating portion has a major axis and a minor axis. This shape is the same as that of the antenna element. Therefore, each radiating portion radiates a polarized wave whose polarization plane is parallel to the major axis of the radiating region and whose resonant frequency is determined by the length of the major axis. Furthermore, the resonant frequency is specifically the frequency of the radio wave whose wavelength is half the length of the major axis.

[0090] For example Figure 8 The first radiating region has a shape where the major axis is parallel to the X-axis and the minor axis is parallel to the Y-axis. Therefore, the surface within the radiating element is... Figure 8 The radiation region of the first radiation area radiates a radio wave whose polarization plane is parallel to the X-axis and whose wavelength is twice the length of the major axis of the first radiation region. Additionally, for example... Figure 8 The third radiating region has a shape where the major axis is parallel to the Y-axis and the minor axis is parallel to the X-axis. Therefore, the surface within the radiating element is... Figure 8 The radiation polarization plane of the third radiation region is parallel to the Y-axis and the wavelength is twice the length of the major axis of the third radiation region.

[0091] Therefore, the radiating element 630, which has multiple radiating parts, can radiate various radio waves with different combinations of polarization planes and wavelengths. That is, the antenna 600 is an antenna with a bandwidth wider than that of a square patch antenna, which only has a single type of radiating part, and unlike an antenna with only a single type of radiating part, it can radiate multiple radio waves with different polarization planes.

[0092] Furthermore, in the radiating element 630, adjacent radiating portions with parallel major axes are connected through a portion of a radiating portion with a perpendicular major axis. For example... Figure 8 The first and second radiating portions are connected through a portion of the third, a portion of the fourth, and a portion of the second additional radiating portion. Furthermore, the first radiating portion is a radiating portion whose surface within the radiating element plane is a first radiating region. The second radiating portion is a radiating portion whose surface within the radiating element plane is a second radiating region. The third radiating portion is a radiating portion whose surface within the radiating element plane is a third radiating region. The fourth radiating portion is a radiating portion whose surface within the radiating element plane is a fourth radiating region. The second additional radiating portion is a radiating portion whose surface within the radiating element plane is a second additional radiating region. Additionally, hereinafter, a location in the space between adjacent radiating portions parallel to their major axes that connects to each other will be referred to as a connecting portion. For example, a portion of the third radiating portion that connects the first and second radiating portions is an example of a connecting portion.

[0093] Therefore, the first and second radiating portions can radiate not only radio waves with wavelengths corresponding to the length of the major axis of each portion, but also radio waves with wavelengths corresponding to the length of the major axis of the portion formed by adding the conducting portion to each portion. Therefore, compared to antennas with multiple radiating portions that are merely spatially separated, antenna 600 can radiate radio waves with a wider bandwidth.

[0094] Furthermore, the antenna 600 has a structure that shares a portion of multiple radiating parts with different long-axis directions, and is capable of radiating radio waves with mutually orthogonal polarization planes. That is, the antenna 600 is not constructed with multiple radiating elements with different long-axis directions in a spatially separated state for radiating radio waves with different polarization planes. Therefore, the antenna 600 can reduce the area occupied by the radiating elements 630 used to radiate radio waves with different polarization planes.

[0095] Therefore, the constructed wireless tag communication device 201 includes an antenna 600 capable of radiating multiple polarization waves with multiple polarization planes or different frequencies. Thus, the probability that the polarization wave radiated by the wireless tag communication device 201 is a polarization wave that the wireless tag can receive is higher than the probability that the polarization wave radiated by a device radiating only one polarization wave is a polarization wave that the wireless tag can receive. Therefore, the wireless tag communication device 201 can reduce situations where information cannot be exchanged with wireless tags due to different types of wireless tags.

[0096] Furthermore, the image forming apparatus 10 thus configured can reduce situations where information cannot be exchanged with wireless tags due to different types of wireless tags. This is not limited to the image forming apparatus 10, but also applies to other sheet processing apparatuses equipped with the wireless tag communication device 201.

[0097] Other sheet processing devices include barcode printers and item reading devices installed in small shops such as clothing stores, where the barcode printer is used for managing the receipt and dispatch of goods. In such cases, sheet material with wireless tags refers to sheet material that is attached to the item.

[0098] (Modified Example)

[0099] Furthermore, one end of the first radiation region parallel to its major axis and one end of the second radiation region parallel to its major axis are not necessarily located at... Figure 8 As shown, on one axis (i.e., end-aligned). That is, one end of the first radiating region in the direction parallel to the major axis and one end of the second radiating region in the direction parallel to the major axis can also be... Figure 7 The positional relationship is as shown. This applies not only to the first and second radiation regions but also to the first additional region. That is, the ends of the first radiation region parallel to the long axis and the first additional region parallel to the long axis are not necessarily on the same axis, and the ends of the second radiation region parallel to the long axis and the first additional region parallel to the long axis are not necessarily on the same axis. Furthermore, in the case of multiple first additional regions, the ends of one first additional region parallel to the long axis and the ends of other first additional regions parallel to the long axis are not necessarily on the same axis. However, end alignment can achieve a higher gain. When the ends are not aligned, the number of edges of the radiation region increases, resulting in power dispersion. Therefore, when the ends are not aligned, the power flowing in the long axis direction is reduced compared to when the ends are aligned. As described above, the radiation part radiates radio waves at a resonant frequency determined by the length of the long axis in the long axis direction, so the more power flowing in the long axis direction, the higher the gain can be obtained. Therefore, end alignment is more preferable than end misalignment.

[0100] Furthermore, the distance between radiating regions parallel to the major axis is preferably within a few millimeters. By setting it to within a few millimeters, the same amount of current flows through each radiating element, allowing the resonant frequency corresponding to each radiating region to be obtained simultaneously. This enables the handling of a wider bandwidth.

[0101] Furthermore, the ends of the third radiation region parallel to the long axis and the fourth radiation region parallel to the long axis are not necessarily located at... Figure 8As shown, on one axis (i.e., end-aligned). That is, one end of the third radiation region parallel to the major axis and one end of the fourth radiation region parallel to the major axis can also be... Figure 7 The positional relationship is as shown. This applies not only to the third and fourth radiation regions but also to the second type of additional region. That is, the end of the third radiation region parallel to its long axis and the end of the second type of additional region parallel to its long axis are not necessarily on the same axis, and the end of the fourth radiation region parallel to its long axis and the end of the second type of additional region parallel to its long axis are not necessarily on the same axis. Furthermore, when there are multiple second type of additional regions, the end of one second type of additional region parallel to its long axis and the ends of other second type of additional regions parallel to their long axes are not necessarily on the same axis. However, end alignment can achieve a higher gain. When the ends are not aligned, the number of edges of the radiation region increases, and the power is dispersed. Therefore, when the ends are not aligned, the power flowing in the long axis direction is reduced compared to when the ends are aligned. As described above, the radiation part radiates radio waves at a resonant frequency determined by the length of the long axis in the long axis direction, so the more power flowing in the long axis direction, the higher the gain can be obtained. Therefore, end alignment is more preferable than end misalignment.

[0102] Furthermore, the third length may be approximately the same as or different from either the first or second length. Furthermore, the fourth length may be approximately the same as or different from either the first or second length, and not necessarily the one approximately the same as the third length. Furthermore, the first length refers to the length of the major axis of the first radiating region. The second length refers to the length of the major axis of the second radiating region. The third length refers to the length of the major axis of the third radiating region. The fourth length refers to the length of the major axis of the fourth radiating region.

[0103] Furthermore, the direction of the long axis of the radiating region is not necessarily perpendicular or parallel to the sheet conveying direction. The direction of the long axis of the radiating region can also be perpendicular or parallel to a direction at a predetermined angle to the sheet conveying direction (hereinafter referred to as the "reference direction"). For example, Figure 7 as well as Figure 8 The X-axis direction is perpendicular to the reference direction. Figure 7 as well as Figure 8 The Y-axis direction can also be parallel to the reference direction.

[0104] Furthermore, when using the wireless tag communication device 201, the user can predetermine which of the power supply lines 641 or 642 the wireless tag uses for information exchange, or the wireless tag communication device 201 can determine this by performing a predetermined process. In the case of user predetermination, for example, the user determines that the power supply line 640, which radiates a polarized wave oriented towards a parallel polarization plane to the wireless tag on the sheet being processed, will be used for information exchange.

[0105] When the wireless tag communication device 201 is determined, the predetermined process is, for example, the following determination process. In this determination process, firstly, under the control of the wireless tag communication control unit 501, the power supply line 640, to which voltage is applied, is switched at predetermined intervals before exchanging information with the wireless tag. Furthermore, for each switch, the intensity of the radiated radio wave and the intensity of the reflected wave from the wireless tag based on that radio wave are measured. The wireless tag communication control unit 501 determines the timing of the switch. The reflected wave is the radio wave radiated by the wireless tag. The wireless tag communication control unit 501 measures the reflected wave. The wireless tag communication control unit 501 ends the switch process at a timing when a reflected wave with an intensity above a predetermined value is observed. At the moment the switch ends, the wireless tag communication control unit 501 determines the power supply line 640, to which voltage is applied, as the power supply line 640 for exchanging information with the wireless tag.

[0106] Furthermore, the first type of additional area is an example of the fifth radiation area. The second type of additional area is an example of the sixth radiation area. The length of the major axis of the first type of additional area is an example of the fifth length. The length of the major axis of the second type of additional area is an example of the sixth length. The transceiver circuit section 502 is an example of a radiation control section. The alignment roller 31 is an example of a conveying component.

[0107] The functions of the image forming apparatus 10 or the wireless tag communication control unit 501 described in the above embodiments can also be implemented by a computer. In this case, it can also be implemented by recording the program for implementing the function on a computer-readable recording medium, reading the program recorded on the recording medium into the computer system, and executing it. Furthermore, "computer system" here refers to a system including hardware such as an OS and peripheral devices. Additionally, "computer-readable recording medium" refers to removable media such as floppy disks, optical disks, ROMs, and CD-ROMs, and storage devices such as hard disks built into the computer system. Moreover, "computer-readable recording medium" can also include media that dynamically maintains the program for a short period of time, such as communication lines that transmit programs via networks such as the Internet or telephone lines, or media that maintains the program for a certain period of time, such as volatile memory inside a computer system serving as a server or client in this case. Furthermore, the program described above can be a program used to implement the above functions, or it can be a program that can implement the above functions in combination with programs already recorded in the computer system.

[0108] According to at least one embodiment described above, by having a wireless tag communication device 201, it is possible to reduce situations where information cannot be exchanged with wireless tags due to different types of wireless tags.

[0109] While several embodiments have been described, these embodiments are merely illustrative and not intended to limit the scope of the invention. These embodiments can be implemented in various other ways, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included within the scope and spirit of the invention, and likewise within the scope of the invention as described in the claims and its equivalents.

Claims

1. A wireless tag communication device comprising an antenna and a radiation control unit, wherein the antenna is a microstrip antenna with radiating elements. The radiating element is a conductor and has the following characteristics: The first radiation region has a major axis in a direction perpendicular to the reference direction and a minor axis in a direction parallel to the reference direction, the length of the major axis being a first length, and the reference direction being at a predetermined angle to the transmission direction of the wireless tag. The second radiation region has a major axis in a direction perpendicular to the reference direction and a minor axis in a direction parallel to the reference direction, the length of which is a second length. The third radiation region has a major axis in a direction parallel to the reference direction and a minor axis in a direction perpendicular to the reference direction, the length of which is the third length. as well as The fourth radiation region has a major axis in a direction parallel to the reference direction and a minor axis in a direction perpendicular to the reference direction, the length of which is the fourth length. The radiation control unit causes the radiation element to radiate polarized waves from at least one of the first radiation region, the second radiation region, the third radiation region, and the fourth radiation region. The first radiation region and the second radiation region are regions of different lengths in a direction perpendicular to the reference direction, and they do not contact or overlap with each other. The third and fourth radiation regions are regions of different lengths in a direction parallel to the reference direction, and they do not contact or overlap with each other. The first and second radiation regions share a portion with the third or fourth radiation region. The wireless tag is capable of receiving polarized waves radiated from the first radiation region, the second radiation region, the third radiation region, and the fourth radiation region.

2. The wireless tag communication device according to claim 1, wherein, The reference direction is the transport direction of the sheet on which the wireless tag is attached.

3. The wireless tag communication device according to claim 1 or 2, wherein, The radiating element also has a fifth radiating region, which has a major axis in a direction perpendicular to the reference direction and a minor axis in a direction parallel to the reference direction, the length of which is the fifth length.

4. The wireless tag communication device according to claim 1 or 2, wherein, The radiating element also has a sixth radiating region, which has a major axis in a direction parallel to the reference direction and a minor axis in a direction perpendicular to the reference direction, the length of which is the sixth length.

5. The wireless tag communication device according to claim 3, wherein, The radiating element also has a sixth radiating region, which has a major axis in a direction parallel to the reference direction and a minor axis in a direction perpendicular to the reference direction, the length of which is the sixth length.

6. A sheet processing apparatus, comprising a conveying component for conveying sheets and a wireless tag communication device, The wireless tag communication device includes an antenna and a radiation control unit. The antenna is a microstrip antenna with radiating elements. The radiating element is a conductor and has the following characteristics: The first radiation region has a major axis in a direction perpendicular to the reference direction and a minor axis in a direction parallel to the reference direction, the length of the major axis being a first length, and the reference direction being at a predetermined angle to the transmission direction of the wireless tag. The second radiation region has a major axis in a direction perpendicular to the reference direction and a minor axis in a direction parallel to the reference direction, the length of which is a second length. The third radiation region has a major axis in a direction parallel to the reference direction and a minor axis in a direction perpendicular to the reference direction, the length of which is the third length. as well as The fourth radiation region has a major axis in a direction parallel to the reference direction and a minor axis in a direction perpendicular to the reference direction, the length of which is the fourth length. The radiation control unit causes the radiation element to radiate polarized waves from at least one of the first radiation region, the second radiation region, the third radiation region, and the fourth radiation region. The first radiation region and the second radiation region are regions of different lengths in a direction perpendicular to the reference direction, and they do not contact or overlap with each other. The third and fourth radiation regions are regions of different lengths in a direction parallel to the reference direction, and they do not contact or overlap with each other. The first and second radiation regions share a portion with the third or fourth radiation region. The wireless tag is capable of receiving polarized waves radiated from the first radiation region, the second radiation region, the third radiation region, and the fourth radiation region.

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