Printing apparatus

Abstract

To provide a printing device configured to prevent electromagnetic waves generated when a motor operates from having influence on a connector.SOLUTION: The printing device is provided with: a motor; a conveying mechanism that conveys a medium by power of the motor; a printing mechanism that performs printing on the medium being conveyed by the conveying mechanism; a printing processor that controls the motor, the conveying mechanism and the printing mechanism; a connector which a cable for communicating with the outside is connected to; a substrate mounted with the printing processor and the connector, which transmits a signal inputted from the connector to the printing processor; a first metal plate partitioning a space between the substrate and the motor; a second metal plate positioned above the substrate and having a through-hole formed therein; a third metal plate; a fourth metal plate; a fifth metal plate; and a sixth metal plate. The first plate to the sixth plate surround the substrate, and the cable is connected to the connector through the through-hole, where the through-hole is covered with a metal cover.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to a printing apparatus.

Background Art

[0002] In recent years, printing apparatuses have been utilized in various environments such as homes and offices, and their development has been actively carried out. For example, Patent Document 1 discloses an exchangeable electrical equipment substrate that has a machine body for holding a main body substrate and a movable body that is detachable from the machine body, and a plurality of exchange substrates are held and movable in the attachment / detachment direction, and an electrical connection / disconnection between the main body substrate and the exchange substrate is made along with this movement.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Generally, a printing apparatus has a radiation source that generates electromagnetic waves. As the radiation source, for example, there is a motor as the power for conveying a medium. In a printing apparatus, various connectors are often provided for communication with the outside. Noise easily enters the connectors, and electromagnetic waves generated from a radiation source such as a motor may enter through the connectors and become noise.

Means for Solving the Problems

[0005] One aspect of the printing apparatus according to the present invention is a motor, a conveyance mechanism that conveys a medium by the power of the motor, a printing mechanism that performs printing on the medium conveyed by the conveyance mechanism, A printing processor that controls the motor, the transport mechanism and the printing mechanism, A connector to which a cable for communicating with the outside is connected, A circuit board on which the aforementioned printing processor and the aforementioned connector are mounted, and which propagates signals input from the connector to the aforementioned printing processor, A first metal plate separates the substrate and the motor, A second metal plate is located above the aforementioned substrate and has through holes, A third metal plate, A fourth metal plate, A fifth metal plate, The sixth metal plate, A printing apparatus equipped with, The first to sixth plates surround the substrate, The cable is connected to the connector via the through-hole. The aforementioned through hole is covered with a metal cover. [Brief explanation of the drawing]

[0006] [Figure 1] A diagram illustrating the functional configuration of a printing device. [Figure 2] A diagram showing the external structure of a printing device. [Figure 3] A diagram showing an example of the internal structure of the enclosure. [Figure 4] This figure shows an example of a transport route for media transported by a printing mechanism. [Figure 5] A schematic perspective view showing the area around the main circuit board of a printing device. [Modes for carrying out the invention]

[0007] Embodiments of the present invention are described below. The embodiments described below illustrate examples of the present invention. The present invention is not limited in any way to the embodiments described below and includes various modifications that are implemented without changing the gist of the present invention. Not all of the configurations described below are necessarily essential to the present invention.

[0008] The printing apparatus according to this embodiment comprises a motor, a transport mechanism for transporting a medium using the power of the motor, a printing mechanism for printing on the medium transported by the transport mechanism, a printing processor for controlling the motor, the transport mechanism and the printing mechanism, a connector to which a cable for communicating with the outside is connected, a substrate on which the printing processor and the connector are mounted and which transmits signals input from the connector to the printing processor, a first metal plate separating the substrate from the motor, a second metal plate located above the substrate and having through holes, a third metal plate, a fourth metal plate, a fifth metal plate and a sixth metal plate. The first to sixth plates surround the substrate, the cable is connected to the connector via the through holes, and the through holes are covered with metal covers. The following description will be given with reference to the drawings.

[0009] In the following description, an inkjet printer, which prints images by ejecting liquid onto a medium, will be used as an example of a printing apparatus according to the present invention. However, the printing apparatus is not limited to an inkjet printer; it may also be a dot matrix printer, thermal transfer printer, laser printer, etc.

[0010] 1. Functional configuration of the printing device Figure 1 is a diagram illustrating the functional configuration of a printing apparatus 1, which is an example of a printing apparatus according to this embodiment. As shown in Figure 1, the printing apparatus 1 includes a printing unit 10. Based on printing information input from a host computer (not shown), the printing apparatus 1 prints a desired image on the medium by having the printing unit 10 deposit ink at predetermined positions on the medium.

[0011] In this embodiment, the medium printed by the printing apparatus 1 is described as a sheet of paper, but the medium used in the printing apparatus is not limited to sheet paper and may be roll paper. Furthermore, the medium is not limited to paper and may be a fibrous material such as a dishcloth or a sheet of plastic.

[0012] The printing unit 10 includes a main circuit board 101, a head circuit board 120, a plurality of ejection heads 130, a media conveyance control unit 140, and a motor 150.

[0013] The main circuit board 101 has a main control circuit 111 that outputs control signals for controlling each part of the printing apparatus 1. The main control circuit 111 is electrically connected to a connector 115 provided on the main circuit board 101. This main control circuit 111 is configured to include a SoC (System On a Chip) including a CPU (Central Processing Unit).

[0014] The main control circuit 111 receives printing information from the host computer via the connector 115 and sends out information for printing. The main control circuit 111 of the main circuit board 101 generates a signal for operating the printing mechanism 160. In other words, a processor provided in the main control circuit 111 of the main circuit board 101 generates a signal for operating the printing mechanism 160 according to an instruction sent via the cable 192.

[0015] Also, the main control circuit 111 conveys the medium on which the printing operation is to be performed based on a signal input from the host computer via the connector 115. Specifically, the main control circuit 111 generates a conveyance control signal PT for conveying the medium on which the printing operation is to be performed and outputs it to the media conveyance control unit 140 via the cable 194. The media conveyance control unit 140 generates a drive control signal for controlling the drive of the motor 150 based on the input conveyance control signal PT and outputs it to the motor 150. Thereby, the motor 150 is driven, and along with the drive of the motor 150, the medium is conveyed along a predetermined conveyance direction.

[0016] Also, the main control circuit 111 generates a printing control signal PC for performing printing on the medium based on a signal input from the host computer via the connector 115 and outputs it to the head circuit board 120 via the cable 192.

[0017] The printing control signal PC is input to the head control circuit 121 included in the head circuit board 120. Based on the input printing control signal PC, the head control circuit 121 generates a print data signal DATA corresponding to each of a plurality of ejection heads 130 having a plurality of nozzles that eject ink onto a medium, and supplies the print data signal DATA to the corresponding ejection head 130. Further, based on the printing control signal PC input from the main control circuit 111, the head control circuit 121 generates a base drive signal dA that serves as a basis for the drive signal COM, and outputs the base drive signal dA to the drive circuit 122. Then, the drive circuit 122 generates a drive signal COM having a waveform defined by the base drive signal dA supplied from the head control circuit 121, and outputs the drive signal COM to the plurality of ejection heads 130.

[0018] Each of the plurality of ejection heads 130 includes a plurality of nozzles that eject ink onto a medium, and a plurality of drive elements that correspond to each of the plurality of nozzles and drive the nozzles so that ink is ejected from the corresponding nozzles when the drive signal COM is supplied. Each of the plurality of ejection heads 130 is electrically connected to the head circuit board 120 via a cable 193. Each of the ejection heads 130 switches whether to supply the drive signal COM supplied from the drive circuit 122 to each of the plurality of drive elements based on the print data signal DATA supplied from the head control circuit 121. Thus, the drive signal COM is supplied to the drive elements corresponding to the nozzles that eject ink onto the medium among the plurality of nozzles, and the drive signal COM is not supplied to the drive elements corresponding to the nozzles that do not eject ink onto the medium among the plurality of nozzles. Thereby, ink is ejected only from the nozzles corresponding to the drive elements to which the drive signal COM is supplied, and no ink is ejected from the nozzles corresponding to the drive elements to which the drive signal COM is not supplied. That is, the plurality of ejection heads 130 switch whether to supply the drive signal COM to each of the plurality of drive elements based on the print data signal DATA output by the head control circuit 121, and eject ink at the timing defined by the print data signal DATA and from the nozzles specified by the print data signal DATA.

[0019] As described above, in this embodiment, the printing apparatus 1 controls the transport of the medium via the medium transport control unit 140 and the operation of the head control circuit 121 on the head circuit board 120, based on information input from the host computer. This selects nozzles that eject ink onto the medium and nozzles that do not eject ink. In other words, the main control circuit 111 controls both the transport of the medium and the timing of ink ejection. As a result, the ejection head 130 can land ink at a desired position on the medium. That is, a dot is formed at a desired position on the medium. As a result, the printing apparatus 1 prints a desired image on the medium.

[0020] In the following description, the configuration including the head circuit board 120 that performs printing operations on the medium under the control of the main circuit board 101, a plurality of ejection heads 130, a medium transport control unit 140, and a motor 150 will be collectively referred to as the printing mechanism 160. That is, the printing unit 10 includes a main circuit board 101 which has a main control circuit 111 that controls the operation of the printing mechanism 160 according to input information. The main control circuit 111 of the main circuit board 101 is an example of a printing processor.

[0021] Furthermore, the connector 115 of the printing device 1 may be a USB port or LAN port for connecting the printing device 1 to an external device using a LAN (Local Area Network) cable or a USB cable. In addition, the printing device 1 may be capable of reading image information stored on a storage medium such as a hard disk or flash memory connected to the USB port or LAN port, and performing printing operations based on the read information. Furthermore, the printing device 1 may be equipped with a scanner unit that acquires image information formed on the medium. In other words, the printing device 1 may be a so-called multifunction device that can both form an image on the medium and acquire the image formed on the medium.

[0022] 2. Structure of the printing device Next, the structure of the printing device 1 will be described. Here, in describing the structure of the printing device 1, the front-to-back direction of the printing device 1 will be referred to as the X direction, the left-to-right direction of the printing device 1 as the Y direction, and the up-and-down direction of the printing device 1, which is the vertical direction, as the Z direction. Furthermore, when specifying the orientation along the X, Y, and Z directions, the tip of the arrow indicating the X direction shown in the diagram may be referred to as the +X side and the starting point as the -X side; the tip of the arrow indicating the Y direction may be referred to as the +Y side and the starting point as the -Y side; and the tip of the arrow indicating the Z direction may be referred to as the +Z side and the starting point as the -Z side.

[0023] Figure 2 is a schematic diagram showing the external structure of the printing device 1. As shown in Figure 2, the printing device 1 comprises a printing unit 10 and a scanner unit 200.

[0024] The printing unit 10 includes a media storage section 141, a media output tray 149, and a housing 170. The media storage section 141 forms a storage space in which media are stored before the printing operation is performed. Specifically, the media storage section 141 is located on the +Z side of the housing 170, and at least a portion of the storage space is installed in a way that it can be pulled out into the housing 170. The media output tray 149 is located on the -Z side of the housing 170 and is used to discharge media after the printing process has been performed.

[0025] The scanner unit 200 is a flatbed type and includes an image sensor or other imaging element (not shown), a scanner circuit board 201 including a scanner control circuit, and a motor 250 for driving the scanner (see Figure 3). The scanner circuit board 201 is equipped with a scanner processor that controls the scanner unit 200. The scanner unit 200 can read images recorded on a medium such as paper as image data via the image sensor. Therefore, the scanner unit 200 functions as an image reading device.

[0026] In the printing apparatus 1 configured as described above, when a printing operation is performed, the media stored in the media storage unit 141 is transported inside the housing 170, and the printing operation is performed on the media during the period in which the media is transported inside the housing 170. After the printing operation is performed, the media is discharged into the media discharge tray 149.

[0027] Figure 3 shows an example of a transport path for a medium transported by a printing mechanism 160 located inside a housing 170. As shown in Figure 3, transport rollers 142, 143, and 144 are provided inside the housing 170. Each of these transport rollers 142 to 144 is a pair of rollers, including a drive roller and a driven roller. The transport rollers 142 to 144 grip the medium between the drive roller and the driven roller, and the drive roller rotates due to the drive of the motor 150 mentioned above, thereby transporting the medium along a predetermined transport direction.

[0028] Specifically, media stored in the media storage section 141 are discharged one by one by the transport roller 142. Because the transport roller 142 discharges media one by one from the media storage section 141, it may be configured to apply pressure to the media, for example, from the -Z side to the + side along the Z direction. The media discharged from the media storage section 141 is held by the transport roller 143 and transported along the transport path to the printing area PA facing the discharge head 130. When the media reaches the printing area PA, the discharge head 130 discharges ink onto the media at a timing based on the print data signal DATA. After that, the ink-covered media is held by the transport roller 144 and transported along the transport path towards the media discharge tray 149, and discharged from inside the housing 170 into the media discharge tray 149.

[0029] Next, the internal structure of the housing 170 of the printing unit 10 will be described. Figure 4 is a diagram showing an example of the internal structure of the printing device 1. Figure 5 is a schematic perspective view showing the area around the main circuit board 101 of the printing device 1. In Figure 5, components such as the communication cable 300, resin cover 400, and housing 170 are omitted in order to allow the components surrounding the main circuit board 101 to be seen.

[0030] As shown in Figure 4, the printing device 1 has a main circuit board 101 and a printing mechanism 160 built into the housing 170. The main circuit board 101 is fixed to the housing 170.

[0031] As already mentioned, the printing mechanism 160 has a motor 150. The printing device 1 includes a first metal plate 181 that separates the main circuit board 101 and the motor 150 within the housing 170, a second metal plate 182 located above the main circuit board 101 (in the -Z direction) and having a through hole 182a, a third metal plate 183, a fourth metal plate 184, a fifth metal plate 185, and a sixth metal plate 186. Note that the fifth metal plate 185 and the sixth metal plate 186 are omitted in Figure 4.

[0032] The first metal plate 181 is provided between the main circuit board 101 and the motor 150 (see Figure 4), and faces the third metal plate 183 with the main circuit board 101 in between. The second metal plate 182 faces the third metal plate 183, which is positioned below the main circuit board 101 (+Z direction), with the main circuit board 101 in between. Furthermore, the fifth metal plate 185 is positioned to the side of the main circuit board 101 (+Y direction), and faces the sixth metal plate 186 with the main circuit board 101 in between.

[0033] Thus, the first plate 181, the second plate 182, the third plate 183, the fourth plate 184, the fifth plate 185, and the sixth plate 186 (the first to sixth plates 181 to 186) surround the main circuit board 101 from the front, back, top, bottom, left, and right. The through hole 182a provided in the metal second plate 182 is covered by a metal cover 188. Here, the metal cover 188 covering the through hole 182a means that it is arranged so that the main circuit board 101 cannot be directly viewed from outside the printing device 1 through the through hole 182a. In other words, the metal cover 188 covering the through hole 182a means that the main circuit board 101 cannot be seen from outside the printing device 1 because it is blocked by the metal cover 188.

[0034] In the example shown in Figure 4, the metal cover 188 serves as both a structural component and a functional support for the scanner unit 200. That is, the printing device 1 further includes a scanner unit 200 for reading documents above the connector 115, and the metal cover 188 is part of the scanner unit 200. On the other hand, although not shown, the metal cover may also be a dedicated cover that covers the through hole 182a.

[0035] Furthermore, the metal cover 188 is located on the underside of the scanner circuit board 201, which houses the scanner processor that controls the scanner unit 200.

[0036] Then, as shown in Figure 4, the communication cable 300 is connected to the connector 115 provided on the main circuit board 101 via the through-hole 182a.

[0037] The metals constituting the first to sixth plates 181 to 186 are not particularly limited and can be any metal or alloy as long as they do not allow electromagnetic waves to pass through. By surrounding the main circuit board 101 with the first to sixth plates 181 to 186, it is possible to suppress the generation of noise on the main circuit board due to external electromagnetic waves.

[0038] As shown in Figure 4, a communication cable 300 for communicating with the outside is connected to a connector 115 provided on the main circuit board 101 via a through-hole 182a formed in the second metal plate 182. Although the through-hole 182a cannot be expected to have an electromagnetic shielding effect, the presence of a metal cover 188 suppresses the intrusion of electromagnetic waves into the connector 115 and the main circuit board 101, thereby reducing the generation of noise.

[0039] As shown in Figure 4, the printing device 1 is provided with a resin cover 400. The resin cover 400 has a notch formed therein that allows the communication cable 300 to pass through. The resin cover 400 has a shape that is flush with the back surface (+X side) of the printing device 1. The resin cover 400 has functions such as preventing dust from entering the connector 155 from the outside and improving the appearance of the back surface of the printing device 1.

[0040] In the example shown in Figure 4, the relative positions of the components are such that, in the direction in which gravity acts, the components are arranged from bottom to top in the following order: print processor (main circuit board 101), connector 115, resin cover 400, metal cover 188, and scanner processor (scanner circuit board 201). In other words, when a virtual horizontal plane (a virtual plane parallel to the XY plane) is moved from bottom to top (from the +Z side to the -Z side), the order in which the components are cut by the virtual horizontal plane is the print processor (main circuit board 101), connector 115, resin cover 400, metal cover 188, and scanner processor (scanner circuit board 201).

[0041] In the examples shown in Figures 4 and 5, the first to sixth plates 181 to 186 are flat, but they may each have independent shapes with protrusions or curved surfaces. Furthermore, the first to sixth plates 181 to 186 are not limited to being separate single plates, but may be any two or more plates integrated together. In addition, in the illustrated examples, the first to sixth plates 181 to 186 are arranged with adjacent plates touching, but they can be arranged arbitrarily as long as noise generation on the main circuit board due to external electromagnetic waves is suppressed, and for example, there may be arrangements where adjacent plates do not touch.

[0042] Furthermore, in the example shown in Figure 4, the communication cable 300 is routed through the resin cover 400 and exited to the rear side of the printing device 1. However, the communication cable 300 may also be routed through the inside of the housing 170 of the printing device 1 and exited, for example, from the side or bottom of the printing device 1. This would allow the printing device 1 to be positioned so that its rear is against a wall, thus saving space.

[0043] 3. Effects and Effects In the printing apparatus 1 according to this embodiment, the main circuit board 101 is covered with metal first plates 181 to sixth plates 186, and the communication cable 300 is connected to the connector 115 via a through hole 182a in the metal second plate 182, and the through hole 182a is covered with a metal cover 188. Therefore, even if electromagnetic waves are generated when the motor 150 operates, noise is less likely to occur in the connector 115 and the main circuit board 101.

[0044] The embodiments and variations described above are merely examples and are not limiting. For example, each embodiment and each variation can be combined as appropriate.

[0045] The present invention includes configurations substantially identical to those described in the embodiments, for example, configurations with the same function, method, and results, or configurations with the same purpose and effect. Furthermore, the present invention includes configurations in which non-essential parts of the configurations described in the embodiments are replaced. Furthermore, the present invention includes configurations that produce the same effects or achieve the same purpose as those described in the embodiments. Finally, the present invention includes configurations that add known technology to the configurations described in the embodiments.

[0046] The following can be derived from the embodiments and modifications described above.

[0047] The printing device is Motor and, A transport mechanism that transports the medium using the power of the motor, A printing mechanism that prints on the medium transported by the transport mechanism, A printing processor that controls the motor, the transport mechanism and the printing mechanism, A connector to which a cable for communicating with the outside is connected, A circuit board on which the aforementioned printing processor and the aforementioned connector are mounted, and which propagates signals input from the connector to the aforementioned printing processor, A first metal plate separates the substrate and the motor, A second metal plate is located above the aforementioned substrate and has through holes, A third metal plate, A fourth metal plate, A fifth metal plate, The sixth metal plate, A printing apparatus equipped with, The first to sixth plates surround the substrate, The cable is connected to the connector via the through-hole. The aforementioned through hole is covered with a metal cover.

[0048] With this printing device, the circuit board is covered with a metal plate, and the cables are connected to the connectors through holes in the metal plate, which are then covered with metal covers. Therefore, even if the motor generates electromagnetic waves when it operates, noise is less likely to occur in the connectors and circuit board.

[0049] In the above printing apparatus, A scanner for reading the document is further provided above the connector, The metal cover may be part of the scanner.

[0050] This printing device allows for the suppression of noise generation from connectors and circuit boards using components from the scanner.

[0051] In the above printing apparatus, The metal cover may be located on the underside of the substrate on which the scanner processor that controls the scanner is mounted.

[0052] This printing device makes it possible to reduce the amount of noise caused by the motor that is generated in the scanner processor.

[0053] In the above printing apparatus, The device further comprises a resin cover that covers the connector into which the cable is inserted, In the direction in which gravity acts, the components may be arranged from bottom to top in the following order: the printing processor, the connector, the resin cover, the metal cover, and the scanner processor.

[0054] This printing device makes it possible to reduce the amount of noise generated by the motor in each processor. [Explanation of Symbols]

[0055] 1...Printing device, 10...Printing unit, 101...Main circuit board, 102...Second circuit board, 111...Main control circuit, 115...Connector, 120...Head circuit board, 121...Head control circuit, 122...Drive circuit, 130...Ejection head, 140...Media transport control unit, 141...Media storage section, 142, 143, 144...Transport rollers, 149...Media discharge tray, 150...Motor, 160...Print Printing mechanism, 170...Housing, 181...First metal plate, 182...Second metal plate, 182a...Through hole, 183...Third metal plate, 184...Fourth metal plate, 185...Fifth metal plate, 186...Sixth metal plate, 188...Metal cover, 191,192,193,194...Cable, 200...Scanner unit, 201...Scanner circuit board, 250...Motor, 300...Communication cable, 400...Resin cover

Claims

1. Motor and, A transport mechanism that transports the medium using the power of the motor, A printing mechanism that prints on the medium transported by the transport mechanism, A main control circuit that generates signals to operate the motor, the transport mechanism, and the printing mechanism, A connector to which a cable for communicating with the outside is connected, A circuit board on which the main control circuit and the connector are mounted, and which propagates signals input from the connector to the main control circuit, A first metal plate separates the substrate and the motor, A second metal plate, located above the aforementioned substrate and having through holes, A third metal plate, A fourth metal plate, A fifth metal plate, The sixth metal plate, A metal cover, A printing apparatus equipped with, The first to sixth plates surround the substrate, The cable is connected to the connector via the through-hole. The metal cover is positioned so as to overlap with the direction of penetration of the through hole. A printing apparatus in which the cable passes between the metal cover and the second plate.

2. A scanner for reading the document is further provided above the connector, The printing apparatus according to claim 1, wherein the metal cover is part of the scanner.

3. The printing apparatus according to claim 2, wherein the metal cover is located below the substrate on which the scanner processor that controls the scanner is mounted.

4. The device further comprises a resin cover that covers the connector into which the cable is inserted, The printing apparatus according to claim 3, wherein, in the direction in which gravity acts, the main control circuit, the connector, the resin cover, the metal cover, and the scanner processor are arranged in that order from the bottom.

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