JP7469895B2 - Printer and media handling device - Google Patents

Description

The present invention relates to a printer and a media transport device.

Conventionally, small printers have been known that are primarily intended for printing photos of around L to 2L size. To make them smaller, some of these printers do not have a paper output tray and are configured to hold the end of the printed recording medium without completely ejecting it.

In printers that do not completely eject the printed recording medium, the user must pick up the paper to prevent the printed recording medium from scattering around, and wait until the printed recording medium is gone before printing again. To achieve this type of paper transport control, an optical sensor for detecting the medium is provided near the paper ejection port.

However, due to the influence of external light entering through the paper output port, there have been cases where the printer has mistakenly detected that the printer is not holding a printed recording medium, even when the printed recording medium is actually being held. Small printers in particular are often used outdoors, meaning that external light is more likely to enter through the paper output port, making false detections more likely.

In Patent Document 1, in a portable printer that uses an optical sensor for detecting paper, a light-shielding member is provided on the side of the opening through which the paper is inserted, closer to the optical sensor than the optical sensor, so as to protrude toward the paper introduction path, thereby preventing external light entering through the opening from reaching the optical sensor.

JP 2017-56703 A

Patent document 1 is a configuration that prevents external light from entering an optical sensor located near the opening where paper is introduced into the printer, and cannot be used to prevent light from entering through the paper discharge port. This is because if the light-shielding member described in patent document 1 is used to prevent external light from entering an optical sensor located near the paper discharge port, the paper being discharged will collide with the light-shielding member, causing transport problems. Another problem is that providing a dedicated light-shielding member leads to increased costs.

The object of the present invention is to suppress erroneous detection caused by the influence of external light entering from the paper outlet in a printer that detects whether a recording medium on which printing has been completed is being held, without using any new components.

The above-mentioned object can be achieved by a printer having a holding means for holding a recording medium on which printing has been completed with a portion of the recording medium exposed to the outside from the paper discharge port, and a detection means for detecting the presence or absence of the recording medium held by the holding means, wherein a portion of the holding means is arranged to cover the detection means and functions as a light-shielding member for preventing external light from entering the detection means from the paper discharge port, and the holding means has a first member and a second member, and holds the recording medium by pressing the recording medium against the second member using the elasticity of the first member .

According to the present invention, in a printer that detects whether a recording medium on which printing has been completed is being held, it is possible to suppress erroneous detection caused by the influence of external light entering from the paper discharge port without using any new components.

FIG. 1 is a perspective view showing an example of the appearance of a printer and an ink ribbon cassette according to an embodiment; FIG. 1 is a block diagram showing an example of the functional configuration of a printer according to an embodiment. FIG. 1 is a diagram showing a portion of an ink ribbon according to an embodiment; FIG. 1 is a cross-sectional view showing a state during a printing operation of a printer according to an embodiment; FIG. 1 is a cross-sectional view showing a state during a printing operation of a printer according to an embodiment; FIG. 1 is a cross-sectional view showing a state during a printing operation of a printer according to an embodiment; Flowchart of printing operation of a printer according to an embodiment FIG. 1 is a top view of a printer according to an embodiment with an upper case and a top frame removed; FIG. 2 is an exploded perspective view of a paper guide member and a paper pressure plate according to the embodiment; FIG. 1 is a perspective view showing a mounting structure of a paper guide member and a paper pressure plate according to an embodiment; BB cross-sectional view of FIG. AA cross-sectional view of FIG.

The present invention will now be described in detail based on exemplary embodiments with reference to the attached drawings. Note that the following embodiments do not limit the invention according to the claims. In addition, although multiple features are described in the embodiments, not all of them are necessarily essential to the invention, and multiple features may be combined in any manner. Furthermore, in the attached drawings, the same reference numbers are used for the same or similar configurations, and duplicate explanations will be omitted.

The following describes an embodiment in which the present invention is applied to a thermal transfer printer. However, the present invention is not particularly dependent on the printing method, and can be applied to printers using other printing methods, such as inkjet printing. It can also be applied to electronic devices equipped with a printer function.

In the following explanation, "image formation" refers to a process of forming an image on a recording medium such as paper by applying a coloring material such as ink to the recording medium or by causing the coloring material contained in the recording medium to develop color using heat or other methods. "Printing" refers to a series of processes from forming an image based on a print command to outputting the recording medium with the image formed from the paper outlet. "Printing paper" is used to include recording media whose main component is other than paper and that can be handled in the same way as paper.

Figure 1 is a diagram showing an example of the appearance of a printer 100 according to an embodiment and a cassette 300 used in the printer 100. Figure 1(a) is a perspective view seen from the top side, and Figure 1(b) is a perspective view seen from the bottom side.

The printer 100 is configured to house a cassette 300, a paper transport mechanism, a power source (e.g., a battery), etc., within the space formed by the upper body case 101-1 and the lower body case 101-2.

The upper body case 101-1 and the lower body case 101-2 form a paper outlet 101-3 at part of the joint on one side of the printer 100. As described below, the printer 100 of this embodiment completes printing with the end of the print paper held in the paper outlet 101-3. The print paper is completely discharged when the user pulls out the print paper 113 from the printer.

An openable and closable cassette cover 101-4 is provided on a side of the printer 100 other than the side on which the paper discharge port 101-3 is formed. Inside the printer 100, a chassis 110 having a cassette mounting section 110-1 is provided. The cassette mounting section 110-1 is accessible when the cassette cover 101-4 is open. The cassette 300 can be mounted in the opening 110-1 by opening the cassette cover 101-4 and inserting the cassette 300 (hereinafter simply referred to as cassette 300) in the direction of arrow 400. The mechanical components inside the printer 100 are housed in a frame in which the chassis 110 supports the bottom and sides, and a top frame 111 (described later) supports the top.

The cassette 300 contains an ink ribbon 114 coated with sublimation ink wound in a roll. The ink ribbon 114 is transported by a transport mechanism of the printer 100. The structure of the cassette 300 will be described in detail later.

The printer 100 is provided with an openable tray cover 101-5 on its bottom. With the tray cover 101-5 open, printing paper 113 (Fig. 4A) can be loaded into the paper storage section 117 (Fig. 4A). When printing, the printer 100's paper feed mechanism transports the printing paper 113 from the paper storage section 117 toward the thermal head. The thermal head transfers various inks applied to the ink ribbon 114 to the printing paper 113 based on the printing data, thereby forming an image on the printing paper 113 that corresponds to the printing data.

A display unit 102 and an operation unit 103 are provided on the top surface of the main body upper case 101-1. The printer 100 also has a communication interface for communicating with external devices. The printer 100 of this embodiment has both a wireless communication interface and a wired communication interface. The communication interface may conform to any communication standard. The printer 100 of this embodiment has a USB interface as an example of a wired communication interface, and is provided on the side with a connector (USB connector 104) for connecting a USB cable. The wireless communication interface may conform to, for example, Bluetooth (registered trademark) or wireless LAN (any of the IEEE 802 series) standards.

The display unit 102 has multiple LEDs, and indicates the state of the printer 100 using lighting modes such as on, off, and blinking, as well as lighting colors and lighting patterns (e.g., blinking cycles). Note that a dot matrix display may be used as the display unit 102, and the state of the printer 100 may be indicated by characters.

The operation unit 103 is a general term for input devices such as buttons and switches operated by the user. In FIG. 1, the operation unit 103 is shown as a power switch. However, one or more other input devices may also be provided.

Fig. 2 is a block diagram showing an example of the functional configuration of the printer 100. In Fig. 2, the same reference numerals are used to designate the same components as in Fig. 1, and duplicated explanations will be omitted.
The main controller 201 has a microprocessor such as a CPU, and for example, transfers a program stored in a ROM 202 to a RAM 203 and executes it to control each part of the printer 100 and realize the functions of the printer 100. The ROM 202 may be, for example, electrically rewritable, and stores programs executable by the CPU of the main controller 201, setting values, etc. The RAM 203 is used to hold programs executed by the CPU of the main controller 201 and values required while the CPU is executing a program. The RAM 203 is also used to temporarily store data received from an external device, and as a buffer memory when the image processing unit 213 performs image processing, etc.

The head temperature detection sensor 204 outputs data representing the temperature of the thermal head 116 to the main controller 201. The environmental temperature sensor 205 outputs data representing the temperature inside the printer 100 to the main controller 201. The main controller 201 corrects the drive signal for the thermal head 116 or puts the drive on hold based on the outputs of the head temperature detection sensor 204 and the environmental temperature detection sensor 205.

The first paper detection sensor 206-1 and the second paper detection sensor 206-2 detect the presence or absence of paper at a specific position in the printer 100. Each of the first paper detection sensor 206-1 and the second paper detection sensor 206-2 detects the presence or absence of paper using a photoreflector. The photoreflector is composed of a light-emitting element that irradiates light toward the paper transport path, and a light-receiving element that detects the amount of incident light. The paper detection sensor determines that paper is present if the amount of incident light (output of the light-receiving element) when the light-emitting element is turned on is equal to or greater than a threshold value, and determines that paper is not present if it is less than the threshold value, and outputs data indicating the determination result to the main controller 201. Note that any sensor that determines the presence or absence of paper based on the amount of incident light can be used for the first paper detection sensor 206-1 and the second paper detection sensor 206-2.

In this embodiment, a first paper detection sensor 206-1 is provided near the paper transport path between the paper storage unit 117 and the thermal head 116, and a second paper detection sensor 206-2 is provided between the paper discharge port 101-3 and the transport roller 124 (Figure 4A). The main controller 201 controls the transport of the print paper based on the detection results of the first paper detection sensor 206-1 and the second paper detection sensor 206-2.

The ribbon detection sensor 207 detects a marker provided on the ink ribbon 114. The ribbon detection sensor 207 may also be a sensor using a photoreflector. The ribbon detection sensor monitors the output of the light receiving element while irradiating the ink ribbon 114 with light from a light emitting element, and when a predetermined output change is detected, it determines that a marker has been detected and notifies the main controller 201. The main controller 201 controls the transport of the ink ribbon 114 based on the notification from the ribbon detection sensor 207.

The print paper 113 and the ink ribbon 114 are transported by a paper transport motor 209. The operation of the paper transport motor 209 is controlled by a motor driver 208 according to instructions from the main controller 201.

The position change motor 210 switches the position of the thermal head 116 between multiple positions, such as the position during image formation and the position during standby or ink ribbon replacement, and drives the phase switching mechanism of the mechanical elements. The operation of the position change motor 210 is controlled by the motor driver 208 according to instructions from the main controller 201.

The communication unit 211 is the communication interface described above. The communication unit 211 communicates with external devices, receives print data and various commands from the external devices, and transmits information about the printer 100 to the external devices. When the main controller 201 receives commands or instructions from the external devices, it executes operations according to those commands or instructions.

The image data input unit 212 receives image data from an external device via the communication unit 211. Note that the function of the image data input unit 212 may be performed by the main controller 201, in which case the image data input unit 212 is not necessary.

The image processing unit 213 applies image processing to the image data received by the image data input unit 212 from an external device. Image processing that the image processing unit 213 can apply may include image data decoding, resizing, various correction processes, etc., but these are merely examples, and other image processing may also be applied. The image processing unit 213 also generates data for printing based on the image data to which the image processing has been applied.

The head driver 214 controls the driving of the thermal head 116 based on the print data generated by the image processing unit 213. The head driver 214 generates an electrical signal to be applied to each of the multiple heating elements provided in the thermal head 116 based on the print data, and outputs it to the thermal head 116. The heating elements of the thermal head 116 convert the electrical signal into thermal energy, and transfer the color material (dye) applied to the ink ribbon 114 to the printing paper.

Figure 3 is a diagram showing an example of the configuration of the ink ribbon 114 according to this embodiment. The ink ribbon 114 has a configuration in which multiple color materials are regularly arranged, one color at a time, in the transport direction. Here, the ink ribbon 114 is for full-color printing, and has yellow (Y), magenta (M), and cyan (C) color materials for image formation. Furthermore, the ink ribbon 114 has an overcoat (OC), which is a colorless and transparent color material for forming a protective layer on the image formation surface of the printing paper. The types of color materials for image formation that the ink ribbon 114 has are just an example, and other color materials may be used. Also, the overcoat color material is not essential.

In this embodiment, the ink ribbon 114 has three color materials for image formation and one color material for overcoat, which are periodically arranged in the transport direction, and markers 114-1 are provided at the boundaries between the different color materials. The markers 114-1 are made of a material that has a reflectance that can be detected by the ribbon detection sensor 207. The markers 114-1 are formed by using the ink ribbon 114 base film or by applying a material.

The ink ribbon 114 is made of a highly heat-resistant base film (such as a PET film) with a thickness of 2 to 10 μm, coated with coloring materials. The coloring materials for image formation are made of dyes, binders, plasticizers, adhesives, etc., and are about 0.2 to 5 μm thick. The coloring materials for the overcoat are made of styrene derivatives, styrene resins, styrene copolymer resins, binders, etc., and are about 0.5 to 5 μm thick. A layer containing a lubricant to reduce frictional resistance and stabilize the running of the ink ribbon 114, and an abrasive to clean the thermal head surface, is coated on the surface of the base film opposite to the surface coated with the coloring materials. Note that the composition and thickness of the paint described here are merely examples.

Of the markers 114-1, the marker that indicates the start of a repeating unit of color material has a different pattern or reflectance from the other markers. In the example of FIG. 3, marker 114-1Y, which is provided immediately before the yellow (Y) color material in the transport direction (or at the boundary between the overcoat color material and the yellow (Y) color material), is the marker that indicates the start of a repeating unit of color material. In the example of FIG. 3, markers 114-1M, 114-1C, and 114-1OC are each composed of a single straight line extending in the width direction of the ink ribbon 114, while marker 114-1Y is composed of two straight lines extending in the width direction of the ink ribbon 114.

The printing operation of printer 100 will be described with reference to FIGS. 4A-4C, which are cross-sectional views of printer 100 in different states during a printing operation, and FIG.
Fig. 4A(a) shows the standby state, Fig. 4A(b) shows the paper feeding state, Fig. 4B(a) shows the state before the start of image formation, Fig. 4B(b) shows the state during image formation, Fig. 4C(a) shows the state after image formation is completed and before the paper discharge operation, and Fig. 4C(b) shows the state of each part of the printer 100 after the paper discharge operation. As will be described later, the paper discharge operation of the printer 100 is completed with part of the print paper held within the printer, and the print paper is not completely discharged from the printer.

When the power is turned on by the operation unit 103, the main controller 201 executes a startup process and the printer 100 goes into a standby state. If an error is detected during the startup process, such as the cassette 300 not being set or there being no printing paper 113 in the paper storage unit 117, the main controller 201 notifies the user of the error via the display unit 102.

The platen roller 115 is provided to transport the printing paper and to press the printing paper against the heating element of the thermal head 116. The thermal head 116 is supported by a thermal head rotation shaft 119 and can move around the thermal head rotation shaft 119 as the axis of rotation. The thermal head 116 is biased by a biasing member (not shown) in the clockwise direction in the figure, i.e., in the direction in which the distance between the platen roller 115 and the thermal head 116 increases. Therefore, in the standby state shown in FIG. 4A(a) and the state after the paper ejection operation shown in FIG. 4C(b), the distance between the platen roller 115 and the thermal head 116 is greater than in other states.

After communication with the external device is possible, when the data to be printed and a print instruction are given in the external device, print instruction information is sent from the external device to the printer 100. The communication unit 211 outputs a print command from the print instruction information to the main controller 201, and outputs the data to be printed to the image data input unit 212. The image processing unit 213 generates print data based on the data obtained from the image data input unit 212, and outputs it to the head driver 214.

Meanwhile, when the main controller 201 receives a print command, it starts the printing operation (Fig. 5). When the main controller 201 starts the printing operation, it controls the position change motor 210 to rotate the thermal head 116 counterclockwise around the thermal head rotation shaft 119. As a result, the main controller 201 moves the thermal head 116 to an intermediate position between the standby position shown in Fig. 4A(a) and the position during image formation shown in Fig. 4B(b) where it is nipped with the platen roller 115, as shown in Fig. 4A(b) (S102).

The position change motor 210 also presses the paper feed roller 121 down from a position where it does not contact the print paper 113 to a position where it contacts the print paper. In the standby position shown in FIG. 4A(a), the paper feed roller 121 is retracted to a position away from the print paper 113. In the intermediate position shown in FIG. 4A(b), the paper feed roller 121 is pressed down to a position where it contacts the print paper 113.

The movement of the thermal head 116 and the paper feed roller 121 by the operation of the position change motor 210 is indirectly achieved by a mechanism that utilizes the driving force of the position change motor 210.

When the movement of the thermal head 116 is completed, the main controller 201 starts the paper feed operation (S103). The pressure plate 120, which is biased toward the paper feed roller 121 by a biasing member (not shown), presses the printing paper 113 stored in the paper storage section 117 against the paper feed roller 121.

The main controller 201 controls the paper transport motor 209 (not shown in FIG. 4A) to rotate the paper feed roller 121 counterclockwise in the figure. The printing paper 113 pressed against the paper feed roller 121 by the pressure plate 120 is transported toward the gap between the thermal head 116 and the platen roller 115 as the paper feed roller 121 rotates. Here, a separation bank section 122 is provided to prevent multiple sheets of printing paper 113 from being transported together. The separation bank section 122 transports only the topmost sheet of printing paper 113 stored in the paper storage section 117, and the second and subsequent sheets stop moving by hitting the separation bank section 122.

When the conveyed print paper 113 is detected by the first paper detection sensor 206-1, the main controller 201 determines that the paper feeding operation is normal. The print paper 113 advances to the left in the figure while moving the rotatably supported switching plate 123 upward, and enters the nip formed by the conveying roller 124 and the conveying driven roller 125.

The transport roller 124 has a number of small protrusions formed thereon that penetrate the back surface (the surface opposite to the surface on which an image is formed) of the printing paper 113 in order to transport the printing paper 113 accurately. The transport roller 124 is driven by a paper transport motor 209 (not shown in FIG. 4A). The paper transport motor 209 is a stepping motor that can accurately control the amount of transport of the printing paper 113. When the printing paper 113 is transported to the nip portion formed by the transport roller 124 and the transport driven roller 125, the main controller 201 controls the position change motor 210 to move the paper feed roller 121 to the standby position shown in FIG. 4A (a). This prevents the printing paper in the paper storage section 117 from being transported further.

It is detected that the transport of the print paper 113 by the transport roller 124 and the transport driven roller 125 continues, and that the rear end of the print paper 113 has passed the position of the first paper detection sensor 206-1. In response to this detection, the main controller 201 further transports the print paper 113 a predetermined amount and then stops the transport. When the transport stops, the rear end of the print paper 113 is to the left of the tip of the switching plate 123.

Next, the main controller 201 conveys the print paper 113 in the reverse direction by a predetermined distance and stops it at the image formation start position shown in FIG. 4B (a) (S104). During conveyance in the reverse direction, the rear end of the print paper 113 passes above the switching plate 123. The print paper 113 then passes below the feed roller 121 and is conveyed into the space between the guide wall 127, which separates and holds the lower part of the battery 126, and the paper storage wall 128.

When the paper feed operation is completed and the print paper 113 stops at the image formation start position, the main controller 201 executes the cueing operation of the ink ribbon 114 (S105). The cueing operation of the ink ribbon 114 is an operation of detecting the marker (marker 114-1Y) that indicates the start of a repeating unit of color material in the ink ribbon 114.

The main controller 201 starts transporting the ink ribbon 114. Specifically, the main controller 201 drives the winding mechanism that engages with the winding shaft 301 provided in the cassette 300 in a counterclockwise direction in the figure using a power source (not shown). This causes the ink ribbon 114 wound around the supply shaft 302 to be wound around the winding shaft 301. The main controller 201 monitors the output of the ribbon detection sensor 207 while winding the ink ribbon 114. Then, when the main controller 201 detects an output corresponding to a marker (marker 114-1Y) that indicates the start of a repeating unit of the color material of the ink ribbon 114, it stops winding the ink ribbon 114.

If the main controller 201 detects the marker 114-1Y within a specified time from the start of transport of the ink ribbon 114, it determines that the marker has been detected correctly and executes S108. On the other hand, if the main controller 201 does not detect the marker 114-1Y within a specified time from the start of transport of the ink ribbon 114, it determines that the marker has not been detected correctly and executes S107.

In S107, the main controller 201 determines that there is an abnormality in the cassette 300, notifies the user of the error via the display unit 102, and executes S128 and S129 (ejects the print paper and ends the printing operation).

In S108, the main controller 201 controls the position change motor 210 to rotate the thermal head 116 counterclockwise around the thermal head rotation shaft 119, and move it to the image forming position shown in FIG. 4B(b). At the image forming position, the ink ribbon 114 and the printing paper 113 are pressed against the thermal head 116 by the platen roller 115.

In S109, the main controller 201 executes image formation processing for the Y component of the print data. The main controller 201 transports the print paper 113 and ink ribbon 114 in the direction of the paper discharge port 101-3. In parallel with the transport, the head driver 214 controls the current applied to the heating element of the thermal head 116 based on the Y component of the print data, so that the Y ink applied to the ink ribbon 114 is transferred to the print paper 113 and an image of the Y component is formed. During image formation, the ink ribbon 114 and print paper 113 are transported at the same speed. For this reason, the ink ribbon transport mechanism provided in the printer 100 incorporates a torque limiter mechanism (not shown) that slips when a load exceeding a certain torque is applied.

After passing under the heating element of the thermal head 116, the ink ribbon 114 and the printing paper 113 are transported in the same direction while maintaining a close contact state for a certain distance, and then transported in a direction away from each other. That is, the printing paper 113 is transported to the left in the figure by the transport roller 124, and the ink ribbon 114 is transported in the direction of the guide shaft 303 provided in the cassette 300 while sliding against the peeling plate 129 that is integrally arranged with the thermal head 116.

When Y component image formation on the printing paper 113 is completed, in S110 the main controller 201 drives the position change motor 210 to retract the thermal head 116 to the intermediate position shown in Figure 4C (a).

Then, in S111, the main controller 201 transports the print paper again to the image formation start position shown in FIG. 4B(a). Then, in S112, the main controller 201 performs cueing of the ink ribbon 114. The cueing here is detection of the marker 114-1M provided at the beginning of the M ink. Then, in S113 to S115, the main controller 201 executes image formation for the M component of the print data in the same manner as in S106, S108, and S109.

When image formation for the M component is completed, the main controller 201 executes image formation for the C component in the same manner as for the M component (S116 to S121). Thereafter, the main controller 201 executes image formation using OC ink to form a protective layer (S122 to S127). When forming an image using OC ink, print data is used to form a protective layer over the entire image formation surface of the printing paper.

When image formation using OC ink is completed, the main controller 201 moves the thermal head 116 to the intermediate position shown in FIG. 4C (a) and then transports the print paper 113 in the direction of the paper discharge port 101-3. After the print paper 113 is detected by the second paper detection sensor 206-2, the main controller 201 continues transporting the print paper 113 for a certain distance according to the paper size, and then stops the transport (S128). The transport stop position of the print paper 113 is the position where the rear end of the print paper 113 passes through the nip between the transport roller 124 and the transport driven roller 125 and the second paper detection sensor 206-2 can detect the presence of the print paper.

When paper ejection is completed in S128, the main controller 201 moves the thermal head 116 to the standby position shown in FIG. 4C(b) in S129, and ends the printing operation. In this way, a full-color image and a protective layer are formed on the printing paper 113 by repeating the image formation operation in the order of yellow, magenta, cyan, and overcoat.

As described above, when the printing process is completed, the rear end of the print paper 113 remains inside the printer 100. This is because the printer 100 does not have a paper output tray, and if the rear end of the print paper is transported outside the printer 100, the print paper 113 will fall. The printer 100 has a member that holds the print paper 113 so that it can be easily pulled out of the printer 100 while preventing the printed print paper 113 from falling. Specifically, as will be described later using Figure 11, paper guide members 130 and 132 that hold the print paper 113 by pinching it from above and below are provided downstream of the transport roller 124 (the paper output port 101-3 side).

Note that, to form the next image, the printed print paper 113 must be removed from the printer 100. Therefore, the main controller 201 determines whether the printed print paper 113 has been removed from the printer 100 based on the output of the second paper detection sensor 206-2. In S130, the main controller 201 determines whether paper has been detected by the second paper detection sensor 206-2, and if it is determined that paper has been detected, it executes S131, and if it is determined that paper has not been detected, it executes S133.

In S131, the main controller 201 starts a display, using the display unit 102, to prompt the user to remove the print paper from the printer after printing has been completed. In S132, the main controller 201 makes a determination similar to that of S130, and if it is determined that paper has been detected by the second paper detection sensor 206-2, it repeats S131, and if it is determined that paper has not been detected, it executes S133.
In S133, the main controller 201 transitions to a print standby state in which the main controller 201 is ready to accept the next print instruction.

Next, the structure of the printer 100 near the paper discharge port 101-3 will be described with reference to FIGS.
6 is a top view of the printer 100 with the main body upper case 101-1 and the top frame 111 removed. A paper pressure plate 131 is attached to the paper discharge port 101-3 side of the paper guide member 130 provided on the top side (upper side). The paper pressure plate 131 covers the upper part of the paper guide member 132 provided on the bottom side (lower side). The paper pressure plate 131 (first member) and the paper guide member 132 (second member) constitute a holding means that holds the print paper 113 after printing is completed with a part of it exposed to the outside from the paper discharge port.

As shown in FIG. 7, the paper pressure plate 131 is formed of an elastic sheet-like member having a generally trapezoidal shape with the upper base facing the paper discharge port 101-3 and the upper base shorter than the lower base. The paper pressure plate 131 has light-blocking properties. The paper pressure plate 131 can be formed, for example, from a sheet-like resin material, but other materials may also be used. The light-blocking properties of the paper pressure plate 131 may be an inherent property of the material forming the paper pressure plate 131, or may be a property added to the material by coloring with a pigment or the like. Here, as an example, a sheet-like member of PET (polyethylene terephthalate) colored with a black pigment is used. The thickness of the paper pressure plate 131 can be, for example, 1 mm or less, but can be determined according to the rigidity of the material used and the required pressing force.

The paper pressure plate 131 has two notches 131-3 in the upper base portion. As a result, the paper pressure plate 131 has three tapered convex portions 131-1 and 131-2 formed on the paper discharge port 101-3 side. As shown in FIG. 6, of the three convex portions, the central convex portion 131-1 (first pressing portion) is larger in both the paper transport direction and the width direction (direction perpendicular to the paper transport direction) than the two convex portions 131-2 (second pressing portions) on either side.

The paper pressure plate 131 has its lower end attached to the paper pressure plate attachment section 130-1 of the paper guide member 130 with double-sided tape or the like, and is supported by a cantilever on the paper guide member 130. This allows the upper end of the paper pressure plate 131 to press the printed print paper 113 from above, and holds the rear end of the printed print paper 113 between it and the paper guide member 132. The printed print paper 113 is held with a portion exposed from the paper outlet 101-3 so that the user can pull it out.

The screws 133 for fixing the paper guide member 132 to the bottom surface of the chassis 110 (not shown) are visible through the two cutouts 131-3 of the paper pressure plate 131. Figure 7 shows a perspective view of the paper discharge section area surrounded by dotted lines in Figure 6, with the paper guide members 130, 132, and the paper pressure plate 131 disassembled and viewed from the paper discharge port 101-3 side.

Figure 8 (a) shows the state in which the paper pressure plate 131 is attached to the paper guide member 130 in Figure 7, and Figure 8 (b) shows the state in which the paper guide members 130, 132, and the paper pressure plate 131 are installed in the printer 100, as viewed from the paper discharge outlet 101-3 side.

Furthermore, in FIG. 6, in the vicinity of the paper discharge section surrounded by a dotted line, the configuration of the B-B cross section above the second paper detection sensor 206-2 (not shown) is shown in FIG. 9, and the configuration of the A-A cross section near the end is shown in FIG. 10.

As shown in Figures 9 and 10, when the paper guide member 130 is installed in the printer 100, the paper pressure plate attachment section 130-1 is inclined downward toward the paper discharge port 101-3. In other words, when the paper guide member 130 is attached to the printer 100, the paper pressure plate attachment section 130-1 is configured to form an acute angle with the top surface of the paper guide member 132 (the surface that guides the recording paper).

As shown in FIG. 7, the top surface of the paper guide member 132 has six guide ribs 132-1 in the width direction, which are ridges that run along the transport direction of the print paper. The back side of the transported print paper is supported by the guide ribs 132-1. The guide ribs 132-1 reduce the contact area between the paper guide member 132 and the print paper 113, contributing to smooth transport.

In the portion of the top surface 132 where the guide rib 132-1 is not present, a base surface 132-2 and a recessed portion 132-3 that is lower than the base surface 132-2 are formed. A sensor board 134 on which a second paper detection sensor 206-2 and a thermistor 135 are mounted is attached to the back side of the base surface 132-2. A cutout is provided in the base surface 132-2 so that the second paper detection sensor 206-2 and thermistor 135 are exposed from the base surface 132-2 (Figure 8 (a)).

A recess 132-3 is formed on the inside of each of the two outermost guide ribs 131-1. Between the two guide ribs 132-1 sandwiched between the central base surface 132-2 and the recess 132-3, there is a countersunk portion 132-4 that receives a screw 133 that attaches the paper guide member 132 to the bottom surface of the printer 100 chassis.

As shown in FIG. 8(a), the paper pressure plate 131 has a flat shape when the paper guide member 130 is not installed in the printer 100. However, when the paper guide member 130 is installed in the printer 100, the tip portion of the central convex portion 131-1 bends along the base surface 132-2 of the paper guide member 132, as shown in FIG. 8(b). The size of the convex portion 131-1 and/or the relative positions of the paper guide members 130 and 132 are determined so that the convex portion 131-1 covers the cutout portion of the base surface 132-2 where at least the second paper detection sensor 206-2 and the thermistor 135 are exposed.

As shown in FIG. 9, the convex portion 131-1 of the paper pressure plate 131 is located on the second paper detection sensor 206-2 when the paper guide member 130 is installed in the printer 100. In addition, the tip portion of the convex portion 131-1 deforms along the base surface 132-2 and is in close contact with the base surface 132-2. Because the paper pressure plate 131 is formed from an elastic sheet material, the convex portion 131-1 (first pressing portion) is biased so as to constantly press against the base surface 132-2.

Since the paper pressure plate 131 has light-blocking properties, it not only covers the top of the second paper detection sensor 206-2, but also deforms so as to fit closely to the paper discharge port 101-3 side of the base surface 132-2, effectively blocking external light entering from the paper discharge port 101-3. This is highly effective in preventing external light entering from the paper discharge port 101-3 from entering the light receiving part of the second paper detection sensor 206-2, which would cause the sensor to erroneously detect that printing paper 113 is present when it is not.

On the other hand, as shown in FIG. 11, the convex portion 131-2 of the paper pressure plate 131 is provided at a position corresponding to the recessed portion 132-3 of the paper guide member 132 when the paper guide member 130 is assembled in the printer 100, and is shorter than the convex portion 131-1. Therefore, the convex portion 131-2 (second pressing portion) of the paper pressure plate 131 does not deform along the recessed portion 132-3 of the paper guide member 132 even when the paper guide member 130 is assembled in the printer 100. The tip of the convex portion 131-2 contacts the recessed portion 132-3 or forms a gap between the recessed portion 132-3 and the convex portion 131-2 that is smaller than the thickness of the printing paper. The convex portion 131-2 (second pressing portion) of the paper pressure plate 131 generates a pressing force on the paper guide member 132 only when there is a printing paper 113 to hold.

The protrusions 131-1 and 131-2 of the paper guide member 132 are lifted upward by the transported print paper 113. As a result, the protrusions 131-1 and 131-2 of the paper pressure plate 131 press the print paper 113 toward the top surface of the paper guide member 132 due to the elasticity of the paper pressure plate 131.

The reason why the tips of the convex parts 131-2 at both ends are not constantly deformed is to prevent creep when no printing paper is present. There is a risk of creep occurring in the convex parts 131-1, which are constantly deformed, and in that case, the pressing force toward the paper guide member 132 will gradually weaken.

The notch 131-3 between the protrusion 131-1 and the protrusion 131-2 of the paper pressure plate 131 is formed to avoid the guide rib 132-1. The paper pressure plate 131 is provided with a protrusion 131-1 that constantly deforms to press the paper guide member 132, and a protrusion 131-2 that deforms to press the paper guide member 132 only when the printing paper 113 being held is present, thereby preventing a decrease in the pressing force due to creep.

In addition, the convex portion 131-1 covering the second paper detection sensor 206-2 is configured to constantly press against the paper guide member 132, improving adhesion with the paper guide member 132 and improving the blocking effect of external light entering from the paper discharge port.

In this embodiment, in a printer having a holding mechanism that holds a recording medium after printing is completed without completely ejecting it, and a sensor that detects the presence or absence of a recording medium held in the holding mechanism, external light entering from the paper discharge port is blocked using a component that constitutes the holding mechanism. Therefore, erroneous detection of the presence or absence of a recording medium due to the influence of external light entering from the paper discharge port can be suppressed without providing a new component for light blocking.

Other Embodiments
Although the above embodiment has been described with reference to a printer, the present invention can be similarly applied to a medium transport device that transports a recording medium. In other words, the present invention does not require a configuration related to image formation, such as a print head or an ink ribbon.

The present invention can also be realized by supplying a program that realizes one or more of the functions of the above-mentioned embodiments to a system or device via a network or a storage medium, and having one or more processors in the computer of the system or device read and execute the program. It can also be realized by a circuit (e.g., an ASIC) that realizes one or more functions.

The present invention is not limited to the above-described embodiments, and various modifications and variations are possible without departing from the spirit and scope of the invention. Therefore, the following claims are appended to clarify the scope of the invention.

100... printer, 101-1... upper body case, 101-2... lower body case, 101-3... paper outlet, 113... printing paper, 114... ink ribbon, 130, 132... paper guide member, 131... paper pressure plate

Claims (11)

a holding means for holding the recording medium on which printing has been completed in a state in which a part of the recording medium is exposed to the outside through a paper discharge port;
a detection means for detecting the presence or absence of a recording medium held by the holding means,
a part of the holding means is disposed so as to cover the detection means and functions as a light blocking member that prevents external light from being incident on the detection means through the paper discharge port ;
A printer characterized in that the holding means has a first member and a second member, and holds the recording medium by pressing the recording medium against the second member using the elasticity of the first member . 2. The printer according to claim 1 , wherein the first member functions as the light blocking member. 3. The printer according to claim 1, wherein the first member has a first pressing portion that presses the second member regardless of whether or not a recording medium is held, and a second pressing portion that does not press the second member when a recording medium is not held. The printer according to claim 3 , wherein the first pressing portion functions as the light blocking member. 5. The printer according to claim 1 , wherein the first member is made of a sheet-like resin material supported by a cantilever. 6. The printer according to claim 1 , wherein the second member has a top surface provided with a plurality of ribs for supporting the recording medium. 7. The printer according to claim 6, wherein the detection means is attached to the top surface of the second member. 8. The printer according to claim 1, wherein the detection means detects that the recording medium is being held by the holding means when an amount of incident light is equal to or greater than a threshold value. A medium conveying device that conveys a recording medium,
a holding means for holding the recording medium on which printing has been completed without completely discharging the recording medium;
a detection means for detecting the presence or absence of a recording medium held by the holding means,
a part of the holding means is disposed so as to cover the detection means and functions as a light blocking member that prevents external light from being incident on the detection means ;
A medium conveying device characterized in that the holding means has a first member and a second member, and holds the recording medium by pressing the recording medium against the second member using the elasticity of the first member . 10. The medium transport device according to claim 9 , wherein the first member functions as the light blocking member. 11. An electronic device that transports a recording medium using the medium transport device according to claim 9 .

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