Rotation detection device, medium transport device, and recording device

Abstract

To prevent a variety of harmful effects caused by attachment of grease.SOLUTION: A pulley 22 as a rotating body is attached, at an end in a thrust direction, with a scale 23 that rotates integrally with the pulley 22 as a rotating body, and a detection unit 24 reads a reading area of the scale 23 to detect the rotation of the pulley as a rotating body. An absorber 30 capable of absorbing liquid is attached to a surface of the scale 23 having the reading area, and if there is liquid attached to the scale 23, absorbs the liquid.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a rotation detection device, a medium transport device, and a recording device. [Background technology]

[0002] A rotation detection device that detects the rotation position of a rotary drive shaft is used to detect the rotation position of a rotating part or the displacement position of a movable member. One such rotation detection device is disclosed in Patent Document 1. A disk-shaped code wheel 50 is attached to one end surface of the support plate 71 via double-sided tape 72. A code portion is formed on the outer periphery of the main surface of the code wheel 50, with light-transmitting regions (slits) and pulse codes 50a, which are light-opaque regions, arranged alternately in an annular shape.

[0003] The photosensor 51 detects the pulse code 50 a on the code wheel 50 , and the fluctuations in the rotation speed and rotation angle of the support plate 71 and the driven roller 47 are recognized via the code wheel 50 . The code wheel 50 is directly or indirectly connected to a rotation drive mechanism such as a gear or pulley, and the rotation drive mechanism is often coated with grease to reduce friction. Note that items with a code portion, such as a code wheel, are also called scales. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-250921 Summary of the Invention [Problem to be solved by the invention]

[0005] When a code wheel or scale is used to detect the rotation of a rotating body, the rotary drive mechanism that rotates the rotating body is located nearby and often uses grease, which can get on the code wheel or scale. In mechanisms that rotate the code wheel or scale and detect it with a photosensor, the adhesion of grease can easily cause various problems.

[0006] The present invention suppresses various adverse effects caused by the adhesion of liquid such as grease. [Means for solving the problem]

[0007] The present invention is configured to include a rotating body that rotates in a circumferential direction, a scale attached to the end of the rotating body in the thrust direction and rotating integrally with the rotating body, a detection unit that detects the rotation of the rotating body by reading the reading area of ​​the scale, and an absorbent attached to the scale and capable of absorbing liquid. In the above configuration, a scale that rotates integrally with the rotor is attached to an end of the rotor in the thrust direction, and a detection unit detects the rotation of the rotor by reading a reading area of ​​the scale. An absorbent that can absorb liquid is attached to the scale and absorbs any liquid adhering to the scale. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic block diagram of a recording apparatus to which a rotation detection device of the present invention is applied; [Figure 2] 1 is a perspective view of a part of a drive mechanism to which a rotation detection device of the present invention is applied; [Figure 3] 1 is a perspective view of a part of a drive mechanism to which a rotation detection device of the present invention is applied; [Figure 4] FIG. 2 is a perspective view of a scale of the rotation detection device. [Figure 5] FIG. 2 is a schematic cross-sectional view of a scale and a rotating body. [Figure 6] FIG. 4 is a schematic diagram showing the positional relationship between a scale and an absorber. [Figure 7] FIG. 10 is a schematic diagram showing the positional relationship between a scale and an absorber according to another modified example. [Figure 8] FIG. 10 is a schematic cross-sectional view of a scale and a rotating body according to a modified example. [Figure 9] FIG. 10 is a schematic diagram showing the positional relationship between a scale and an absorber according to a modified example. [Figure 10] FIG. 10 is a perspective view of a part of a drive mechanism to which a rotation detection device according to a modified example is applied. [Figure 11] FIG. 2 is an enlarged perspective view of a portion of the drive mechanism. [Figure 12] FIG. 2 is a perspective view showing a rotation detection device used in a drive mechanism. [Figure 13] FIG. 10 is a perspective view of a part of a drive mechanism to which a rotation detection device according to a modified example is applied. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic block diagram of a recording apparatus to which the rotation detection device of the present invention is applied. In the figure, the recording device 10 is an inkjet printer. The recording unit 11 moves a print head (not shown) two-dimensionally relative to the recording paper, depositing droplets of colored ink from the print head at predetermined positions on the surface of the recording paper to record desired characters, symbols, designs, etc. The print head moves back and forth in a direction roughly perpendicular to the recording paper transport direction, and the recording paper is moved along a predetermined transport path by a transport unit 12. The direction in which the print head moves back and forth is called the main scanning direction, and the direction in which the recording paper is transported is called the sub-scanning direction. In this embodiment, the recording device 10 is an inkjet printer, but it may also be another type of recording device, such as a laser printer. The print head is not limited to one that moves back and forth in the main scanning direction, but may also be one that is fixed in a predetermined position, such as a line head.

[0010] The touch panel 13 displays predetermined information to the user based on the image signal and outputs an operation signal corresponding to the user's touch operation. The communication unit 14 communicates with the sender of the print data to send and receive various data. The control unit 15 is connected to the recording unit 11, the conveying unit 12, the touch panel 13, and the communication unit 14, and controls the entire recording device 10.

[0011] The recording unit 11 and the transport unit 12 are equipped with movable parts. The power source that drives the movable parts of the recording unit 11 and the transport unit 12 is an electric motor, and the rotational force of the drive shaft of the electric motor is transmitted to each component via a gear mechanism, causing the component to undergo a predetermined displacement. For example, the transport unit 12 is equipped with transport rollers that come into contact with the recording paper and move it along the transport path, and when the drive shaft of the electric motor rotates, the transport rollers also rotate.

[0012] At this time, the number of rotations the transport roller needs to make is determined depending on how far the recording paper needs to be transported. In such cases, a rotation detection device is used to detect the rotation angle of the transport roller. Rotation detection devices are used for a variety of purposes, such as detecting not only the rotation angle of the transport roller but also the amount of movement of the print head in the main scanning direction.

[0013] 2 and 3 are perspective views of a part of a drive mechanism to which the rotation detection device of the present invention is applied. As shown in the figure, a gear mechanism 21 is formed, consisting of multiple gears of various shapes, and these gears also employ pulleys and belts. One of the gear mechanisms 21 includes a pulley 22 as a rotating body, which has a roughly cylindrical shape and is equipped with a belt groove. The cylindrical pulley 22 rotates in the circumferential direction around the axis of the cylinder. The bottom or end face of the cylindrical shape corresponds to the end of the rotating body in the thrust direction, and a scale 23 formed in a roughly disk shape is attached to this end and rotates integrally with the rotating body, the pulley 22.

[0014] In this embodiment, the rotating body is the pulley 22 that transmits power, but the rotating body is not limited to this and may be the rotation shaft of the pulley 22, or a gear or the rotation shaft of a gear that transmits power. The rotation of the pulley or gear can be detected. The scale 23 has a code portion 23a with many slits formed at regular intervals on its outer periphery, and a detection portion 24 having a U-shaped photosensor that can hold the code portion 23a is provided near the underside of the scale 23. The scale 23 and detection portion 24 constitute a rotation detection device. When the scale 23 rotates, the slits in the code portion 23a move between the photosensors in the detection portion 24, causing the transmitted light to turn on and off between the light-emitting element and light-receiving element that face each other across the code portion 23a, and the amount of rotation of the scale 23 and the pulley 22 is detected based on the number of on / offs detected by the detection portion 24. The code portion 23a is formed by a slit penetrating the scale 23, so both sides of the scale 23 can be considered to be the reading area. In this embodiment, the slit is formed around the entire circumference, but the code portion 23a may be formed only in a part of the rotating pulley 22. For example, if only the number of rotations is to be detected, the slit may be formed in only one place in the circumferential direction.

[0015] In the scale 23 of this embodiment, the code portion 23a has slits, and the light-emitting element and the light-receiving element face each other, sandwiching the plate-like scale 23. In other words, the detection unit 24 faces both sides of the scale 23. However, the code portion 23a does not need to be slits. Reflective members may be formed like slits at regular intervals on only one side of the scale 23, and the detection unit 24 may be arranged facing only this side. The light-emitting element may illuminate the code portion 23a, and the light-receiving element may detect the amount of rotation of the scale 23 and pulley 22 based on the blinking of reflected light corresponding to the slit-like reflecting member. In this case, the reading area of ​​the scale 23 is the surface on which the reflective member is formed.

[0016] As shown in FIG. 2, a gear mechanism 21 is disposed near the pulley 22 to rotate it, and the gear mechanism 21 is coated with grease to reduce friction. When the gear mechanism 21 operates, there is a possibility that the grease will be scattered around as it rotates. Since the scale 23 is located within the area where the grease is scattered, the grease will adhere to the scale 23. If the grease adheres to the code portion 23a of the scale 23, there is a risk of reading errors occurring. Furthermore, if the grease adheres to the portion of the scale 23 where it is attached to the pulley 22, the adhesive strength will decrease, and there is a risk of the scale falling off.

[0017] FIG. 4 is a perspective view of the scale of the rotation detection device, FIG. 5 is a schematic cross-sectional view of the scale and the rotor, and FIG. 6 is a schematic diagram showing the positional relationship between the scale and the absorber. The end face of the cylindrical pulley 22, which is a rotating body, is a flat circular surface, and the end face of the pulley 22 and the disk-shaped scale 23 are aligned concentrically and fixed with a circular first double-sided tape 25. As shown in FIG. 6, the diameter of the first double-sided tape 25 is approximately the same as the diameter of the pulley 22. Also, a doughnut-shaped absorber 30, whose inner circumference is slightly larger than the diameter of the pulley 22 and whose outer circumference is slightly larger than the inner circumference, is fixed to the same surface of the scale 23 with a second double-sided tape 26 of approximately the same shape. However, the absorber 30 may be larger than the second double-sided tape 26. The absorber 30 is made of a material that easily absorbs liquid, such as a sponge-like material or a paper-like material. In this way, by providing the absorber 30 on the reading surface where the reading area of ​​the scale 23 is located, it is possible to absorb grease adhering to the reading surface of the scale 23. This makes it possible to prevent reading errors when grease adheres to the scale 23. Note that the reading surface refers to the entire surface on the side that is read, not just the area that is read.

[0018] Furthermore, the scale 23 is fixed to the rotating pulley 22 by a first double-sided tape 25, and the absorber 30 is fixed to the scale 23 by a double-sided tape 26 that is different from the first double-sided tape 25. Fixing with double-sided tape enables the absorber 30 to be attached with a simple configuration. However, the first double-sided tape 25 and the second double-sided tape 26 may each be a single piece of double-sided tape or multiple pieces of double-sided tape. Furthermore, the first double-sided tape 25 and the second double-sided tape 26 may be combined into a single piece of double-sided tape. The absorber 30 in this embodiment has substantially the same shape as the second double-sided tape 26, and the inner circumference of the second double-sided tape 26 is slightly larger than the diameter of the pulley 22. Therefore, the absorber 30 is slightly larger than the diameter of the rotating body, which is the pulley 22, and so the absorber 30 is spaced apart from the rotating body. However, the absorber 30 does not have to be spaced apart from the rotating body. If the absorber 30 comes into contact with the rotating pulley 22, there is a risk of friction when the rotating body rotates. By separating the absorber 30 from the rotating body, such a problem can be prevented. Furthermore, even if there is an error in the hole diameter of the absorber 30 due to variations in parts, installation can be easily performed by previously setting the size to allow for separation.

[0019] In this embodiment, the reading area is on both sides of the scale 23, so the absorber 30 is attached to the first surface where the reading area is located. The absorber 30 does not need to be attached to the entire first surface, but only needs to be attached to at least a portion of the first surface. For example, since the doughnut shape is, in other words, connected in a circle in the circumferential direction, the absorber 30 is attached to the entire circumferential direction of the first surface where the reading area is located. "At least a portion" does not necessarily mean that it covers the entire circumference in the circumferential direction, but it is also possible to provide multiple absorbers 30 at intervals, or to provide one in only one location. If provided on at least a portion of the surface, the grease in the vicinity can be absorbed, and the effect of reducing reading failures in the vicinity can be obtained.

[0020] FIG. 7 is a schematic diagram showing the positional relationship between a scale and an absorber according to another modified example. In this way, even if the absorber 30 is formed separately into two arc-shaped inner absorber bodies 30a and two arc-shaped outer absorber bodies 30b, the absorber bodies 30 are arranged over 360 degrees when the axis of the scale 23 is used as the reference, which is equivalent to the absorber being attached over the entire circumference in the circumferential direction. This also means that the absorber 30 is attached so as to cover the entire circumference of the attachment surface in the circumferential direction. By providing the absorber 30 around the entire circumference of the scale 23, no matter where in the circumference the grease adheres, the absorber can be positioned in the direction of gravity or centrifugal force of the adhesion part as the rotating body rotates, and the grease adhered to the scale can be absorbed. This makes it possible to further reduce reading errors when grease adheres to the scale 23. Apart from the circumferential direction, the absorber may be provided at any position in the radial direction as long as it is provided on at least a part of the reading surface.

[0021] The outer peripheries of the absorber 30 and the second double-sided tape 26 are located inside the reading area so as not to cover the code portion 23a, which is the reading area. Therefore, the detection unit 24 reads the reading area on the first surface, and the absorber 30 is attached to an area on the first surface excluding the reading area. By attaching the absorber 30 while avoiding the reading area, it is possible to prevent reading errors caused by the absorber 30. It is sufficient to avoid the reading area, and it is not necessary to attach the absorber 30 to the entire reading surface excluding the reading area. In this embodiment, since the code portion 23a is formed with a slit, both sides of the scale 23 become first sides on which the reading area is formed. Therefore, the mounting surface on which the scale 23 is mounted to the rotating body is also the side on which the reading area is located. In this case, the absorber 30 provided on one side can suppress reading errors and simultaneously suppress falling off. In this embodiment, the absorber 30 is attached to the side of the scale 23 that is also the mounting surface, which can be the first side, but the absorber 30 may be attached to both sides of the scale 23. Furthermore, in a configuration in which the reading area is formed on one side of the scale 23, the detection unit 24 can be arranged on the same side of the mounting surface, making it easier to apply a rotation detection device. On the other hand, in a configuration in which the reading area is formed on one side of the scale 23, the mounting surface can be the surface opposite the surface on which the reading area is located. When the mounting surface and the surface on which the reading area is located are on opposite sides, the detection unit 24 can be located on the opposite side of the mounting surface, eliminating obstacles in the installation position and making it easier to position the rotation detection device. In this case, reading failures may be suppressed by attaching absorbent material 30 to the first surface on which the reading area is formed, or falling off may be suppressed by attaching absorbent material 30 to the mounting surface, or reading failures and falling off may be suppressed by attaching absorbent material 30 to both surfaces. At this time, various arrangements are possible, such as the arrangement of the absorbent material 30 on the reading surface. For example, by providing the absorber 30 around the entire circumference of the scale 23, no matter where grease adheres in the circumference, the rotation of the rotating body will position the absorber 30 in the direction of gravity or centrifugal force of the adhesion part, so that the grease adhering to the scale 23 can be absorbed. This makes it possible to further suppress peeling of the scale 23 when grease adheres to it.

[0022] 6, a hole is also formed in the center of the first double-sided tape 25, but this is to correspond to the shapes of the scale 23 and the pulley 22, and the presence or absence of the hole does not have any particular effect. Here, the pulley 22, which is a rotating body, is fixed concentrically with the scale 23, so the absorber 30 is attached to the rotation axis core portion of the mounting surface formed on the scale 23. Here, the rotation axis core portion is an area on the mounting surface of the scale 23 that includes the rotation axis of the scale 23. Furthermore, since the absorber 30 has approximately the same shape as the end face of the pulley 22 and is attached to this end face, the absorber 30 is attached around the rotation axis core portion of the mounting surface of the scale 23. By providing the absorber 30 on the mounting surface of the scale 23, it is possible to absorb grease adhering to the mounting surface of the scale 23 and prevent grease from falling off when it adheres to the scale 23. Of course, this mounting surface refers to the entire surface on the side to be mounted, not just the area to be glued. The mounting surface of the scale 23 may be the reading surface.

[0023] Next, the operation of this embodiment having the above configuration will be described. When printing is performed using the inkjet printer, which is the recording device 10, the transport unit 12 starts operating, the recording paper moves along a predetermined transport path, and the print head of the recording unit 11 moves back and forth to perform recording. In the moving parts of the recording unit 11 and the transport unit 12, the electric motor rotates, causing the gear mechanism 21 and pulley 22 to rotate.

[0024] When the gear mechanism 21 operates, the grease adhering to the gears is forced outward from the rotation axis by centrifugal force, which can cause it to splatter around depending on the balance of temperature and viscosity. The splattered liquid grease will adhere to the scale 23 near the gear mechanism 21. In conventional cases, the grease adhering to the scale 23 would move outward due to centrifugal force and reach the code portion 23a near the outer periphery of the scale 23, and may enter a slit, for example. If a foreign object enters a slit, the detection unit 24 will no longer be able to detect that the slit is open, and will recognize that the slit is not rotating even though it actually passes through the detection unit 24, resulting in an error in the amount of rotation. The scattering or flowing of grease is not limited to that caused by centrifugal force, but also includes that caused by gravity to flow downward.

[0025] However, in this embodiment, because the absorber 30 is attached to the scale 23, even when grease scatters, the liquid grease is absorbed by the absorber 30. Therefore, even if the scale 23 rotates, the grease does not flow out along the surface of the scale 23 to the outer periphery. Because the grease does not flow to the outer periphery, it is possible to prevent the grease from reaching the cord portion 23a and causing problems in rotation detection.

[0026] FIG. 8 is a schematic cross-sectional view of a scale and a rotating body according to a modified example, and FIG. 9 is a schematic view showing the positional relationship between the scale and an absorber according to the same modified example. In this modified example, the diameter of the first double-sided tape 27 is smaller than the diameter of the pulley 22, the inner circumference of the donut-shaped second double-sided tape 28 is larger than the outer diameter of the first double-sided tape 27 but slightly smaller than the diameter of the pulley 22, and the outer circumference of the second double-sided tape 28 is approximately the same as the outer diameter of the absorber 30.

[0027] In this way, the pulley 22, which is a rotating body, is fixed to the scale 23 by both the first double-sided tape 27 and the second double-sided tape 28. Furthermore, although a small gap is formed between the first double-sided tape 27 and the second double-sided tape 28, this gap is closed by the end face of the pulley 22. If a region of the end of pulley 22, which is a rotating body, that is closer to the center of rotation of the rotating body is called a first region, then scale 23 is fixed to the first region with first double-sided tape 27. If a region of the end of pulley 22, which is a rotating body, that is farther from the center of rotation than the first region is called a second region, then the end of pulley 22 and scale 23 are fixed to the second region with second double-sided tape 28. Then, absorber 30 is fixed to scale 23 with second double-sided tape 28.

[0028] As shown in FIG. 5 , if the end face of the pulley 22 is attached to the scale 23 only with the first double-sided tape 25 and the absorber 30 is attached with a small gap by the doughnut-shaped second double-sided tape 26, the grease may first adhere to the side of the pulley 22 and then flow down the side of the pulley 22 toward the scale 23. The grease is then absorbed by the absorber 30, but it also wets the side of the first double-sided tape 25. In other words, while providing the absorber 30 as shown in FIG. 5 can somewhat reduce reading errors and scale detachment caused by grease compared to a configuration without the absorber 30, in some cases, the grease may seep into the adhesive surface between the first double-sided tape 25 and the scale 23. If the grease continues to penetrate further, the first double-sided tape 25 and the scale 23 may peel off.

[0029] However, as shown in Figure 8, if the second double-sided tape 28 has an inner peripheral shape that reaches the end face of the pulley 22, when the grease flows down the side of the pulley 22 toward the scale 23, the grease is absorbed by the absorber 30 and wets the exposed surface of the second double-sided tape 28. However, although the grease reaches the surface of the second double-sided tape 28, it does not penetrate the second double-sided tape 28 and penetrate into the adhesive surface between the scale 23. As a result, peeling between the first double-sided tape 27 and the scale 23 can be prevented. In this way, the grease adhering to the pulley 22, which is a rotating body, and the second double-sided tape 28 on its end side is absorbed by the absorber 30. At this time, although the adhesive strength of the second double-sided tape 28 may decrease, since the grease does not adhere to the first double-sided tape 27, the scale 23 and the pulley 22 can be maintained firmly attached, and the pulley 22 can be more effectively prevented from falling off. Note that in this embodiment, the absorber 30 and the pulley 22 are sized to be spaced apart in advance, but even in a configuration in which the absorber 30 and the pulley 22 are in close contact, there is a risk of gaps occurring due to component variations, etc. Therefore, in a configuration in which the absorber 30 and the pulley 22 are in close contact, the attachment method shown in FIG. 8 can also be effective.

[0030] In the recording device 10 of this embodiment, the drive of the transport unit that transports the medium can be detected. In addition to the configuration that transports the medium, a rotation detection device is used in the configuration that moves the recording head up and down to define the distance between the recording head and the medium, and in the configuration that moves the stacker, cover, etc. forward and backward or opens and closes. Figures 10 to 12 show a part of a drive mechanism according to a modified example to which the rotation detector of the present invention is applied. Figure 10 is a perspective view showing a part of the drive mechanism to which the rotation detector is applied, Figure 11 is an enlarged perspective view thereof, and Figure 12 is a perspective view showing the rotation detector used in this drive mechanism. As shown in FIG. 10, the transport unit 112 is provided with a carriage shaft 112a, and when the drive shaft of an electric motor (not shown) rotates, the carriage shaft 112a moves up and down by a mechanism connected to a gear mechanism 121.

[0031] 11 and 12, the gear mechanism 121 is rotationally driven via the rotation shaft of the electric motor 121b. A disc-shaped scale 123 is connected to the rotation shaft of the electric motor 121b on the opposite side to the gear mechanism 121, and rotates integrally with the rotation shaft. A detector 124 is disposed adjacent to the scale 123, and the detector 124 detects the amount of rotation of the scale 123 and the electric motor 121b.

[0032] Even in such a configuration, by attaching doughnut-shaped absorber 130 with double-sided tape to the surface of scale 123 where the reading area is located, absorber 130 can effectively absorb grease scattered by gear mechanism 121, preventing the grease from reaching the reading area and preventing any problems with detecting the amount of rotation. Also, by attaching absorber 30 to the attachment surface, it is possible to prevent it from falling off, or absorber 30 may be attached to both surfaces.

[0033] FIG. 13 is a perspective view of a part of a drive mechanism according to a modified example to which the rotation detection device of the present invention is applied. This drive mechanism drives the stacker 201. A stacker drive motor 202 has a motor pinion 202a fixed to its rotation shaft, and rotates a stacker drive gear 204 via a gear mechanism 203. The stacker drive gear 204 is engaged with a linear rack 201a formed on the stacker 201, so when the stacker drive gear 204 rotates, it moves the rack 201a and the stacker 201 linearly according to the direction of rotation.

[0034] Even in such a drive mechanism, it is necessary to detect the amount of rotation in the gear mechanism 203 in order to control the amount of movement of the stacker 201, and so a scale 205 and a detection unit 206 are provided. However, because the gear mechanism 203 is disposed close to the scale 205, the grease used in the gear mechanism 203 adheres to the scale 205, which can prevent the detection unit 206 from correctly detecting the amount of rotation of the scale 205.

[0035] Even with such a drive mechanism, by attaching a doughnut-shaped absorber 210 with double-sided tape to the surface of the scale 205 where the reading area is located, the absorber 210 can effectively absorb the grease scattered by the gear mechanism 203, preventing the grease from reaching the reading area and preventing any problems with detecting the amount of rotation. Also, by attaching an absorber 30 to the attachment surface, it is possible to prevent the grease from falling off, or the absorber 30 may be attached to both surfaces. The rotation detection device has a variety of uses. When applied to a recording device 10, it can detect the drive of the transport unit 11. Such a transport unit 11 generally includes rollers (whether drive rollers or driven rollers) that transport the medium, belts, etc., and the amount of rotation of these drive shafts can be detected. The transport unit 11 can be anywhere from paper feed to paper discharge, not just transport before and after recording. The rotating body can be the rotating shaft itself that drives the transport roller, a support member configured coaxially with the rotating shaft, gears that make up the gear train that transmits driving force to the rotating shaft, a pulley that drives the transport belt, a motor that serves as a drive source, etc.

[0036] Finally, a medium transport device can be configured by including the above-described rotation detection device and a transport unit that transports a medium, and the rotating body drives the transport unit. Furthermore, a recording device can be configured by including this medium transport device and a recording section that performs recording on a medium such as recording paper. Furthermore, a recording device can be configured by including a rotation detection device that detects the rotation of the drive mechanism according to the modified example and a recording section that records on a medium. The application of the rotation detection device of the present invention is not limited to recording devices.

[0037] It goes without saying that the present invention is not limited to the above-described embodiments. The mutually replaceable components and configurations disclosed in the above embodiments may be appropriately changed and applied. Although not disclosed in the above embodiments, members and configurations that are publicly known and can be mutually substituted for the members and configurations disclosed in the above embodiments may be appropriately substituted, and their combinations may be changed and applied. Although not disclosed in the above embodiments, members and configurations may be substituted by those skilled in the art based on publicly known techniques as substitutes for the members and configurations disclosed in the above embodiments, and the combinations may be changed and applied. is disclosed as an embodiment of the present invention. [Explanation of symbols]

[0038] 10...recording device, 11...recording unit, 12...transport unit, 13...touch panel, 14...communication unit, 21...gear mechanism, 22...pulley, 23...scale, 23a...code unit, 24...detection unit, 25...first double-sided tape, 26...second double-sided tape, 27...first double-sided tape, 28...second double-sided tape, 30...absorber, 30a...inner absorber, 30b...outer absorber, 112...transport unit, 112a...carriage shaft, 121...gear mechanism, 121b...electric motor, 123...scale, 124...detection unit, 130...absorber, 201...stacker, 201a...rack, 202a...motor pinion, 203...gear mechanism, 204...stacker drive gear, 205...scale, 206...detection unit, 210...absorber.

Claims

1. a rotating body that rotates in a circumferential direction; a scale attached to an end of the rotor in a thrust direction and rotating integrally with the rotor; a detection unit that detects rotation of the rotating body by reading a reading area of ​​the scale; an absorbent attached to the scale and capable of absorbing liquid; A rotation detection device comprising:

2. 2. The rotation detection device according to claim 1, wherein the absorber is attached to a first surface on which the reading area is located.

3. 3. The rotation detector according to claim 2, wherein the absorber is attached to at least a portion of the first surface.

4. the detection unit reads the reading area on the first surface; 4. The rotation detector according to claim 2, wherein the absorber is attached to an area of ​​the first surface excluding the reading area.

5. the rotating body is attached to a rotation axis portion of a mounting surface formed on the scale, The absorber is attached to the mounting surface around the rotation axis portion.

5. The rotation detection device according to claim 1, wherein the rotation detection device comprises: a first end of the first shaft;

6. 6. The rotation detector according to claim 5, wherein the absorber is attached to the attachment surface so as to cover a portion of the attachment surface over the entire circumference in the circumferential direction.

7. 6. The rotation detector according to claim 5, wherein the mounting surface is a surface opposite to a surface on which the reading area is located.

8. 6. The rotation detector according to claim 5, wherein the mounting surface is a surface on which the reading area is located.

9. the scale is fixed to the rotating body by double-sided tape, The absorber is fixed to the scale by a double-sided tape different from the double-sided tape.

9. The rotation detection device according to claim 1, wherein the rotation detection device is a rotation detecting device.

10. a first region of the end portion of the rotating body that is close to a rotation center of the rotating body is fixed to the scale by a first double-sided tape; a second region of the end of the rotating body that is farther from the rotation center than the first region is fixed to the scale by a second double-sided tape; The rotation detecting device according to claim 9, wherein the absorber is fixed to the scale by the second double-sided tape.

11. 11. The rotation detector according to claim 1, wherein the absorber is spaced apart from the rotating body.

12. 12. The rotation detection device according to claim 1, wherein the rotating body is a gear or a rotation shaft of a gear that transmits power.

13. The rotating body is a pulley or a rotating shaft of a pulley that transmits power.

12. The rotation detection device according to claim 1, wherein the rotation detection device is a rotation detecting device.

14. A rotation detection device according to any one of claims 1 to 13; a transport unit that transports the medium, The medium transport device, wherein the rotating body drives the transport unit.

15. The medium transport device according to claim 14; A recording device comprising a recording unit for recording on the medium.

16. A rotation detection device according to any one of claims 1 to 13; and a recording unit for recording on a medium.

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