JP2005305940A - Liquid storage member, liquid level detector, and liquid jet apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To accurately detect the remaining quantity of a liquid in a liquid storage member by a simple constitution. <P>SOLUTION: This liquid level detector is equipped with a prism part 70 which makes light from a light-emitting element 55 coming from an incidence part 73, and which enables the light to be emitted through the inside toward a light-sensitive element 56 from an outgoing part 74. A leading end surface 72, which can emit the light, passing through the inside, toward a reflecting surface of a film 64, is provided midway through the prism part 70. The leading end surface 72 is arranged in a position to get gradually close to the reflecting surface when the film 64 is bent along with a reduction in ink in an ink storage part 66, and provided in the state of allowing the incidence of reflected light from the close reflecting surface so as to make the light pass through the outgoing part 74. The remaining quantity of the ink in the ink storage part 66 can be detected according to the quantity of outgoing light from the outgoing part 74, which is changed along with a change in a distance between the leading end surface 72 and the reflecting surface of the film 64. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a liquid storage member that stores liquid such as ink, a liquid amount detection device, and a liquid ejection device, and in particular, has a liquid storage portion having a flexible surface such as a film and consumes liquid. Accordingly, the present invention relates to a liquid storage member, a liquid amount detection device, and a liquid ejection device whose volume is reduced by bending a flexible surface.

  As a liquid ejecting apparatus that includes a liquid ejecting head capable of ejecting liquid as liquid droplets and ejects various liquids from the liquid ejecting head, for example, liquid ink is used as ink droplets for ejecting objects such as recording paper. And an image recording apparatus such as an ink jet printer that performs recording by discharging and landing.

  In general, this type of liquid ejecting apparatus is configured to detachably mount a liquid storing member that stores liquid, and to discharge the liquid in the liquid storing member from the liquid ejecting head as droplets. is there. In the liquid ejecting apparatus configured as described above, if the liquid storage member is used up and the use is continued as it is, the liquid cannot be ejected. There is a possibility that bubbles may enter the nozzles, resulting in ejection failure, or the liquid ejecting head to generate heat and be damaged. Therefore, it is desirable to adopt a configuration that notifies the user of the remaining liquid amount in the liquid storage member so that the user can grasp the appropriate replacement timing of the liquid storage member.

  Various means have been proposed as means for detecting the remaining amount of liquid in the liquid storage member. For example, there has been proposed one in which a plate-shaped detection plate is attached to one planar area of a liquid storage portion disposed inside the liquid storage member main body, and the amount of liquid consumption is detected according to the position of the detection plate. (For example, refer to Patent Document 1).

Japanese Patent Laid-Open No. 11-70665

  The one disclosed in Patent Document 1 is provided with a switch capable of contacting a part of the detection plate on the liquid storage member main body side, and a near end is detected by contacting a part of the detection plate to this switch. It is configured as follows. However, there is a possibility that a detection error may occur due to a positional shift between the switch and the liquid storage unit or a tilt of the detection plate in a biased direction.

  The present invention has been made in view of such circumstances, and an object thereof is to detect the remaining amount of liquid in the liquid storage member more accurately with a simple configuration.

The liquid storage member of the present invention has been proposed in order to achieve the above object, and includes a liquid storage part that stores liquid and a liquid outlet part that guides the liquid in the liquid storage part,
At least a part of the liquid storage part is configured as a flexible surface that bends as the liquid decreases, and is a liquid storage member having at least a part of the flexible surface as a reflection surface,
Provided with an optical waveguide that allows light from the light emitting element to be incident from the incident part and to be emitted from the emitting part toward the light receiving element through the inside,
The optical waveguide has a detection part in the middle capable of emitting light passing therethrough toward the reflecting surface,
The detection unit is arranged at a position where the reflection surface gradually approaches when the flexible surface bends as the liquid in the liquid storage unit decreases, and the emission unit receives reflected light from the adjacent reflection surface. To be passed through,
The present invention is characterized in that the remaining amount of liquid in the liquid storage part can be detected based on the amount of light emitted from the emission part that changes with a change in the distance between the detection part and the reflection surface.

  According to the above configuration, the remaining amount of liquid in the liquid storage unit is detected based on the amount of light emitted from the emission unit of the optical waveguide that changes with a change in the distance between the detection unit of the optical waveguide and the reflection surface of the liquid storage unit. Since it was comprised, the liquid storage member which can detect the liquid residual amount more correctly with a simple structure can be provided.

  In the above configuration, it is desirable that the detection unit is provided in a state in which light passing through the optical waveguide is incident at a detection angle smaller than a critical angle of total reflection at a boundary between the detection unit and the liquid. .

  According to this configuration, in a state where the reflection surface (flexible surface) of the liquid storage unit is separated from the detection unit and the liquid is in contact with the detection unit, most of the light from the incident unit is separated from the detection unit. The light can be transmitted to the liquid side, and thereby the amount of light emitted from the light emitting portion can be reduced as much as possible. Therefore, the difference in the amount of light emitted from the emitting portion between the state where the reflecting surface is separated from the detecting portion and the state where the reflecting surface is close to the detecting portion is increased, and the detection accuracy can be further improved.

In this configuration, it is desirable to employ a configuration in which the detection angle is set to approximately 45 °.
Note that “approximately 45 °” means that the detection angle includes a state where the detection angle slightly deviates back and forth from 45 °.

  Moreover, the surface facing the said flexible surface in the said liquid storage part is comprised as a base part produced with the hard member, and the structure by which the said optical waveguide is arrange | positioned at this base part can be employ | adopted.

  In addition, it is desirable that at least a region of the reflecting surface that comes into contact with the detection unit is mirror-finished.

  According to this configuration, in a state where the mirror-finished region of the reflection surface is in contact with the detection unit, the light from the incident unit is more easily reflected, and the amount of light emitted from the emission unit is increased as much as possible. Therefore, the difference in the amount of light emitted from the light emitting part between the state in which the reflecting surface is separated from the detecting part and the state in which it is close to the detecting part becomes larger, and the detection accuracy can be further improved.

Further, two surfaces facing each other of the liquid reservoir are configured as a first flexible surface and a second flexible surface, respectively.
In the optical waveguide, a first reflection region facing the first flexible surface and a second reflection region facing the second flexible surface are provided from the incident portion except the detection portion to the emission portion. The light from the light emitting element is obliquely incident on the first reflection region from the incident portion, and is directed toward the emission portion while repeating incidence and reflection alternately in the first reflection region and the second reflection region. Configured to be able to proceed inside,
The detection unit is provided in the middle of the first reflection region,
It is possible to employ a configuration in which the amount of light emitted from the emission unit changes with a change in the distance between the detection unit and the first flexible surface.

Further, two surfaces facing each other of the liquid reservoir are configured as a first flexible surface and a second flexible surface, respectively.
The light guide includes a first reflection region facing the first flexible surface and a second reflection region facing the second flexible surface, extending from the incident portion to the emission portion. The light from the incident part is obliquely incident on the first reflection area, and the inside can proceed toward the emission part while repeating the incidence and reflection alternately in the first reflection area and the second reflection area. Composed of
A first detector is provided in the middle of the first reflective region, and a second detector is provided in the middle of the second reflective region,
Depending on the separation state or contact state of the first flexible surface with respect to the first detection unit and the separation state or contact state of the second flexible surface with respect to the second detection unit, the amount of light emitted from the emission unit is Changing configurations can also be employed.

  According to this configuration, even if either the first flexible surface or the second flexible surface is in contact with the first detection unit or the second detection unit, the other is separated from the first detection unit or the second detection unit. In the state where the first flexible surface and the second flexible surface are in contact with the first detection unit and the second detection unit, respectively, the amount of light emitted from the emission unit is small. Therefore, in this state, it can be configured not to be detected as the remaining amount of the liquid in the liquid storage unit is small. As a result, it is possible to prevent a malfunction that is erroneously determined to be near-end even though the remaining amount of liquid in the liquid reservoir is not near-end.

  In this configuration, it is preferable that the first reflection region other than the first detection unit and the second reflection region other than the second detection unit in the optical waveguide are mirror-finished. The liquid is preferably stored in a liquid-tight manner.

Further, the liquid amount detection device of the present invention includes a light emitting element that emits light toward an incident portion of a liquid storage member that employs each of the above-described configurations, and a light receiving element that receives light from the emission portion of the liquid storage member. And
The remaining amount of the liquid in the liquid storage portion can be detected according to the amount of light received by the light receiving element.

  In the above-described configuration, it is preferable that the state in which the remaining amount of liquid in the liquid storage unit becomes small can be detected according to the amount of light received by the light receiving element.

Further, the liquid ejecting apparatus of the present invention is equipped with a liquid storage member that employs each of the above-described configurations,
A liquid ejecting head capable of ejecting the liquid in the liquid storage member as droplets and the liquid amount detecting device having the above-described configuration are provided.

  Hereinafter, the best mode for carrying out the present invention will be described with reference to the drawings. In the following, as a kind of liquid ejecting apparatus of the present invention, an ink jet recording head to which an ink cartridge corresponding to the liquid storage member of the present invention is detachably mounted (a kind of liquid ejecting head: hereinafter referred to as a recording head). ) Is provided as an example (hereinafter abbreviated as a printer).

  FIG. 1 is a plan view showing the configuration of the printer 1. The printer 1 includes a frame 2 and a platen 3 disposed in the frame 2, and a platen is rotated by a paper feed roller (not shown) rotated by driving of a paper feed motor 47 (see FIG. 3). A recording paper (a kind of recording medium or discharge target: not shown) is conveyed onto the sheet 3. A guide rod 4 is installed in the frame 2 in parallel with the platen 3, and a carriage 5 is slidably supported on the guide rod 4. The carriage 5 is connected to a driving belt 7 connected to a pulse motor 6 and a timing belt 9 installed on an idle pulley 8. The carriage 5 is reciprocated along the guide rod 4 in the main scanning direction perpendicular to the paper feeding direction by driving the pulse motor 6.

  In addition, a recording head 10 as a liquid ejecting head is mounted on the carriage 5 on the surface (bottom surface) facing the platen 3. A sub tank 11 for supplying ink (a kind of liquid in the present invention) to the recording head 10 is mounted on the upper surface of the carriage 5 opposite to the recording head 10. In the present embodiment, four sub tanks 11a to 11d are arranged side by side corresponding to four types of inks of black, cyan, magenta, and yellow.

  A cartridge holder 13 on which the ink cartridge 12 is detachably mounted is provided on one side of the frame 2 (right side in FIG. 1). In the present embodiment, four ink cartridges 12 a to 12 d are mounted on the cartridge holder 13 corresponding to the four colors of ink. The ink cartridges 12a to 12d are connected to the air pump 15 via air tubes 14a to 14d, and air from the air pump 15 is supplied to the ink cartridge 12. The ink is supplied to each sub tank 11 through the ink supply tube 16 (16a to 16d) by the pressurization in the ink cartridge 12 by the air.

  In addition, the cartridge holder 13 is provided with an optical sensor 37 (see FIG. 3) used to detect a state (near end) where the remaining amount of ink stored in each ink cartridge 12 has become small. Yes. The near-end detection using this optical sensor 37 will be described later.

  FIG. 2 is a partial cross-sectional view for explaining the configuration of the recording head 10. The recording head 10 includes a case 19, a vibrator unit 20 housed in the case 19, a flow path unit 21 joined to the bottom surface (tip surface) of the case 19, and the like. The case 19 is made of, for example, an epoxy resin, and the vibrator unit 20 is accommodated therein. The vibrator unit 20 is a laminated type manufactured by cutting piezoelectric plates in which piezoelectric layers and electrode layers are alternately laminated into a comb-like shape, and can be expanded and contracted in a direction perpendicular to the lamination direction. The piezoelectric vibrator (a kind of pressure generating element) 22 is provided.

  The flow path unit 21 is configured by joining a nozzle plate 24 to one surface of the flow path forming substrate 23 and an elastic plate 25 to the other surface of the flow path forming substrate 23. The flow path unit 21 is provided with a reservoir 26 to which ink is supplied from the sub tank 11 side, an ink supply port 27, a pressure chamber 28, a nozzle communication port 29, and a nozzle opening 30. A series of ink flow paths from the ink supply port 27 to the nozzle opening 30 via the pressure chamber 28 and the nozzle communication port 29 are formed corresponding to each nozzle opening 30.

  The nozzle plate 24 is a thin metal plate having a plurality of nozzle openings 30 formed in a row at a pitch (for example, 180 dpi) corresponding to the dot formation density. In the present embodiment, the nozzle plate 24 is made of a stainless steel plate, and a plurality of nozzle openings 30 (nozzle rows) are provided. One nozzle row is composed of, for example, 180 nozzle openings 30. In the present embodiment, a total of four nozzle rows are formed on the nozzle plate 24 so as to correspond to the respective sub tanks 11a to 11d (ink cartridges 12a to 12d).

  The elastic plate 25 has a double structure in which a flexible elastic film is laminated on a metal plate. The elastic plate 25 is provided with a diaphragm portion 31 that changes the volume of the pressure chamber 28. The diaphragm portion 31 has an island portion 32 to which the tip surface of the piezoelectric vibrator 22 is joined. The island portion 32 is formed by partially removing the surrounding plate material by etching or the like. ing. The elastic plate 25 is provided with a compliance portion 33 that seals a part of the reservoir 26. The compliance portion 33 is produced by removing the plate material in the region facing the opening surface of the reservoir 26 by etching or the like, similar to the diaphragm portion 31, and absorbs the pressure fluctuation of the liquid stored in the reservoir 26. Function as.

  Since the tip surface of the piezoelectric vibrator 22 is joined to the island portion 32, the volume of the pressure chamber 28 can be changed by extending and contracting the free end portion of the piezoelectric vibrator 22. As the volume changes, pressure fluctuations occur in the ink in the pressure chamber 28. The recording head 10 uses this pressure fluctuation to eject ink droplets from the nozzle openings 30.

  FIG. 3 is a block diagram showing an electrical configuration of the printer 1. The printer 1 is roughly composed of a printer controller 35, a print engine 36, and an optical sensor 37. The printer controller 35 includes an external interface (external I / F) 39 for receiving print data from an external device such as a host computer, a RAM 40 functioning as a work area for storing various data, and the like for various data processing. ROM 41 storing a control routine, a control unit 42 that controls each unit, an oscillation circuit 43 that generates a clock signal CK, a drive signal generation circuit 44 that generates a drive signal to be supplied to the recording head 10, and printing An internal interface (internal I / F) 45 for outputting ejection data, drive signals, and the like obtained by developing the data into a dot pattern to the recording head 10 is provided.

  The print engine 36 includes a recording head 10, a pulse motor 6, and a paper feed motor 47. The recording head 10 has a shift register (SR) 49 in which ejection data is set, a latch circuit 50 that latches ejection data set in the shift register 49, a level shifter 51 that functions as a voltage amplifier, and a piezoelectric vibrator 22. A switch circuit 52 that controls the supply of drive signals and the piezoelectric vibrator 22 are provided.

  The optical sensor 37 includes a light emitting element 55 formed of a semiconductor laser and a light receiving element 56 formed of a photodiode or the like. In the present embodiment, the light sensor 55 corresponds to the ink cartridges 12a to 12d. And a total of four sets of light receiving elements 56 (light emitting elements 55a to 55d and light receiving elements 56a to 56d). The optical sensor 37 is electrically connected to the control unit 42. The control unit 42 controls light emission from the light emitting element 55 and controls a light reception signal corresponding to the amount of light received by the light receiving element 56. The data is output to the unit 42. Then, the control unit 42 detects the near end of the ink stored in the ink storage chamber 65 (see FIG. 4 and the like) of the ink cartridge 12 based on the light reception signal output from the optical sensor 37 (light receiving element 56). That is, the liquid amount detection device of the present invention is configured by the optical sensor 37, the control unit 42, and optical waveguides (prism units 70 and 83) described later.

  Next, the ink cartridge 12 will be described. 4A and 4B are diagrams for explaining the configuration of the ink cartridge 12. FIG. 4A is a plan view of the ink cartridge 12 as viewed from above, and FIGS. 4B and 4C are lines AA in FIG. It is sectional drawing and BB sectional drawing. The ink cartridge 12 is generally composed of a case 59 that is a cuboid-shaped hard member having an open top surface, and a lid member 60 that covers the opening of the case 59. The case 59 and the lid member 60 are made of, for example, a synthetic resin such as polypropylene. FIG. 4A shows a state where the lid member 60 is not shown and the upper surface of the case 59 is opened.

  The case 59 is formed so as to surround a hollow box-shaped case main body 61, an upper opening surface 61 ′ of the case main body 61, an enclosure wall 62 to which the lid member 60 is attached, and an internal space of the case main body 61 ( The ink outlet port 63 communicates with the ink storage chamber 65). A flexible film 64 is fixed to the upper opening surface 61 ′ of the case body 61 in a liquid-tight state, and the film 64 and the case body 61 define an internal space as an ink storage chamber 65. An ink reservoir 66 is configured. In the ink storage chamber 65, ink introduced from an ink injection port (not shown) is stored. The film 64 is formed by laminating polypropylene, a gas barrier layer, nylon or the like.

  An upper opening surface 61 ′ of the case body 61 is formed lower than the upper opening surface 62 ′ of the surrounding wall 62, and a film 64 is attached to the upper opening surface 61 ′ and a lid member is formed on the upper opening surface 62 ′. When 60 is attached, an airtight air chamber 67 is formed by each surface of the lid member 60, the film 64, and the surrounding wall 62.

  The ink outlet 63 is configured to be able to lead out the ink stored in the ink storage section 66, that is, in the ink storage chamber 65 to the outside (sub tank 11 side), and a valve 63 ′ is disposed therein. . When a supply needle (not shown) connected to the ink supply tube 16 is inserted into the ink outlet 63, the tip of the supply needle is opened by pushing the valve 63 'into the back side (ink storage chamber 65 side). Thus, the ink in the ink storage chamber 65 is led out from the ink outlet 63. The ink derived from the ink outlet 63 is supplied to the sub tank 11 side through the ink supply tube 16.

  An air supply unit 68 to which the air tube 14 is connected protrudes from the side surface of the case body 61 where the ink outlet 63 is formed. As shown in FIG. 4C, an air introduction port 68 ′ communicating with the air chamber 67 is formed through the air supply unit 68. The air introduction port 68 ′ is opened from the lateral hole opened in parallel with the bottom surface of the case body 61 and from the terminal portion (end portion on the ink storage chamber 65 side) of the lateral hole upward (to the lid member 60 side). In addition, it is configured to have an L-shaped cross section from a vertical hole opened on the air chamber 67 side, so that pressurized air sent from the air pump 15 through the air tube 14 is supplied to the air chamber 67. It has become.

  When air is supplied to the air chamber 67, the pressure in the air chamber 67 increases to atmospheric pressure or higher, and the film 64 is pressed downward (on the bottom surface side of the case body 61). The film 64 is bent downward by this pressing force, and the ink in the ink storage chamber 65 is pressurized, whereby the ink is led out from the ink outlet 63. For this reason, even when the remaining amount of ink in the ink storage chamber 65 is small, by supplying air from the air pump 15 to the air chamber 67, the film 64 is bent to pressurize the ink in the ink storage chamber 65. be able to. Therefore, even when the remaining amount of ink is small, the ink can be forcibly led out from the ink cartridge 12. That is, it can be said that the film 64 that divides one surface of the ink reservoir 66 is configured as a flexible surface that bends as the ink decreases. Moreover, it is a surface facing this film 64, Comprising: The bottom part of the case main body 61 as a hard member is equivalent to a kind of base part in this invention.

  On the bottom surface of the ink reservoir 66 (case body 61), for example, a prism portion 70 (corresponding to a kind of optical waveguide in the present invention) formed of a light transmissive member such as acrylic or glass is disposed. The prism portion 70 is made of polycarbonate in this embodiment. This prism portion 70 is formed in a substantially V shape by a rectangular columnar first waveguide 71a and a second waveguide 71b that intersect each other at 90 °, and a tip portion where these waveguides 71a and 71b intersect, That is, a tip surface 72 (corresponding to a kind of detection unit in the present invention) is formed in the middle of the optical waveguide, which forms an angle of 45 ° with respect to the axial direction of each of the waveguides 71a and 71b.

The end surface of the first waveguide 71 a opposite to the tip surface 72 faces the light emitting element 55 of the optical sensor 37 in a state where the ink cartridge 12 is mounted on the cartridge holder 13, and the light from the light emitting element 55 is transmitted to the first waveguide 71 a. The incident portion 73 is incident. The incident portion 73 is a plane orthogonal to the axial direction of the first waveguide 71a. On the other hand, the end surface of the second waveguide 71b opposite to the tip surface 72 faces the light receiving element 56 of the optical sensor 37 in the mounted state, and the light reflected by the tip surface 72 with respect to the light receiving element 56 is reflected. An emission part 74 that can emit light is formed. The emission part 74 is a plane orthogonal to the axial direction of the second waveguide 71b.
That is, the prism unit 70 is configured to be able to receive light from the light emitting element 55 from the incident unit 73 and emit the light from the emitting unit 74 toward the light receiving element 56 through the inside.

  The prism portion 70 has a front end surface 72 protruding from the bottom of the ink storage portion 66 into the ink storage chamber 65 by a height H so as to face the film 64, and an incident portion 73 and an emission portion 74 of the ink storage portion 66. It is fixed to the ink reservoir 66 in a state of being located on the outside (outside of the ink cartridge 12). The surface of the film 64 on the ink storage chamber 65 side (the surface facing the front end surface 72 of the prism portion 70) is a reflective surface that is mirror-finished by laminating or vapor-depositing a metal foil such as aluminum. It has become. The film 64 is separated upward (from the lid member 60 side) from the front end surface 72 in a state where the ink in the ink storage chamber 65 is full, but as the ink is led out from the ink outlet 63. By being bent, the tip surface 72 is gradually approached. When the ink remaining amount in the ink storage chamber 65 is small (near-end state), the reflection surface of the film 64 is in contact with the front end surface 72. In addition, regarding mirror processing of the film 64, it should just be given with respect to the area | region which contacts the front end surface 72 at least.

  The light emitted from the light emitting element 55 of the optical sensor 37 is incident on the incident portion 73 of the prism portion 70 substantially in parallel with the axial direction of the first waveguide 71a, and passes through the first waveguide 71a to the front end surface 72. Is set to reach. As described above, the distal end surface 72 is configured by a surface having an angle of 45 ° with respect to the axial direction of the first waveguide 71 a, so that light incident from the incident portion 73 is incident on the distal end surface 72. Is incident at an angle of approximately 45 °.

  Here, the refractive index of polycarbonate, which is the material of the prism portion 70, is approximately 1.59 for light of a certain wavelength emitted from the light emitting element 55 in the present embodiment, and for example, the refractive index of aqueous ink is About 1.33. Therefore, the critical angle of total reflection at the boundary between the tip surface 72 and the ink in a state where the ink is in contact with the tip surface 72 (a state where the reflection surface of the film 64 is separated from the tip surface 72) is approximately 57 °. It is. That is, the front end surface 72 is a surface having an angle smaller than the critical angle at the boundary with the ink (hereinafter referred to as a detection angle θd) with respect to the light path from the incident portion 73. Further, since the angle formed by the detection unit 72 and the axis of the second waveguide 71b is also set to 45 ° which is the detection angle θd, the light reflected at the detection angle θd by the detection unit 72 is the second angle. The light travels straight in the waveguide 71b substantially parallel to the axial direction of the second waveguide 71b, and is emitted from the light emitting portion 74 to reach the light receiving element 56.

  In the prism unit 70 configured as described above, in a state where the reflection surface of the film 64 is separated from the detection unit 72 and the ink is in contact with the detection unit 72, the critical angle at the boundary between the tip surface 72 and the ink. Is larger than the detection angle θd, most of the light incident from the incident portion 73 side to the detection portion 72 at the detection angle θd is directed toward the ink side, that is, the ink storage chamber 65 side (or the reflection surface side of the film 64). The amount of light emitted from the emission part 74 is small. On the other hand, in a state where the reflection surface of the film 64 is in contact with the detection unit 72, most of the light incident on the detection unit 72 from the incident unit 73 side at the detection angle θd is reflected to the emission unit 74 side by the reflection surface of the film 64. Therefore, the amount of light emitted from the emission part 74 increases rapidly. That is, the amount of light emitted from the light emitting portion 74 changes according to the change in the position (distance) of the film 64 with respect to the tip surface 72 of the prism portion 70.

  In the printer 1 configured as described above, the remaining amount of ink in the ink reservoir 66 (ink reservoir 65) is detected based on the change in the amount of light emitted from the emitter 74 of the prism unit 70. In the present embodiment, based on the difference between the amount of light emitted from the emitting portion 74 in the separated state (non-contact state) of the reflecting surface of the film 64 with respect to the front end surface 72 and the amount of emitted light from the emitting portion 74 in the same contact state. The near end of the remaining amount of ink in the storage unit 66 is detected. Hereinafter, this near-end detection will be described.

  FIG. 5 is a diagram illustrating a state in which the ink remaining amount in the ink storage chamber 65 is relatively large and the reflection surface of the film 64 is separated from the front end surface 72 of the prism unit 70. First, the control unit 42 drives the light emitting element 55 of the optical sensor 37 to emit (irradiate) light to the prism unit 70 of the ink cartridge 12. The light emitted from the light emitting element 55 enters the first waveguide 71a from the incident portion 73 of the prism portion 70, and enters the distal end surface 72 at the detection angle θd. In the state shown in FIG. 5, the ink is in contact with the front end surface 72, and as described above, the critical angle at the boundary between the front end surface 72 and the ink is larger than the detection angle θd. Most of the light transmitted to the ink storage chamber 65 side. On the other hand, the amount of light reflected by the distal end surface 72 and emitted from the emission portion 74 and received by the light receiving element 56 is very small. In this state, that is, when the reflecting surface of the film 65 is separated from the front end surface 72 of the prism unit 70, the control unit 42 has a relatively small amount of light emitted from the emitting unit 74 (light reception signal output from the light receiving element 56). Does not judge near-end.

  FIG. 6 is a diagram illustrating a state in which the remaining amount of ink in the ink storage chamber 65 is small and the film 64 is in contact with the leading end surface 72. In this state, most of the light incident on the front end surface 72 is reflected toward the emitting portion 74 side by the reflecting surface of the film 64. Therefore, the amount of light emitted from the emitting unit 74 increases rapidly compared to the state of FIG. 5, and a light reception signal corresponding to the amount of received light is output from the light receiving element 56 to the control unit 42. In response to this, the control unit 42 determines that the ink remaining amount in the ink storage unit 66 has become near-end. Specifically, the storage means such as the ROM 41 stores a table indicating the relationship between the amount of light emitted from the light emitting unit 74, that is, the level of the light receiving signal of the light receiving element 56 and the remaining amount of ink. With reference to this table, when the received light signal exceeds a value (threshold value) corresponding to near end, it is determined as near end.

  Note that the remaining amount of ink when the control unit 42 determines near end is arbitrarily set by adjusting the protrusion amount H (see FIG. 4B) of the leading end surface 72 from the bottom of the ink storage unit 66. It is possible. Therefore, it is of course possible to detect a state in which there is almost no remaining ink by aligning the protrusion amount H to substantially zero, that is, aligning the front end surface 72 on the same surface of the bottom of the ink reservoir 66. Further, the threshold value is a value that can reliably detect the state in which the film 64 is in contact with the front end surface 72, that is, a value that is equal to or slightly lower than the value of the received light signal corresponding to the amount of light emitted from the emitting portion 74 in this state. It is desirable to be set to.

  Further, as described above, since the ink is kept in a liquid-tight state by the film 64 and the case body 61, the film 64 comes into contact with the front end surface 72 more reliably as the ink is consumed, and the ink is stored in the container. It is possible to prevent problems such as a decrease in detection accuracy due to leakage to the outside or bubbles entering the ink storage chamber 65 and adhering to the front end surface 72, and light scattering at this portion.

  When the near end is detected, the control unit 42 turns on or blinks, for example, a lamp (not shown) indicating that the ink is near end among the display lamps provided on the surface of the casing of the printer 1. By performing the control, the user is notified that the remaining amount of ink in the ink cartridge 12 has become small. As a result, the user can grasp the more appropriate replacement timing of the ink cartridge 12, so that the ink can be used without waste, and the running cost burden on the user can be reduced. Further, it is possible to prevent problems such as damage to the recording head due to the recording operation being continued in a state where the ink in the ink cartridge 12 is empty.

  It is also possible to adopt a configuration in which the control unit 42 outputs information indicating the near end to an external device such as a host computer via the external I / F 39. In this case, the external device side can display the remaining amount of ink in each ink cartridge 12 on the display device based on the near-end information. For example, a bar whose length changes according to the remaining amount of ink is displayed so that the user can easily visually recognize the remaining amount of ink in the ink cartridge 12, or printing with the remaining ink. The number of possible images can be displayed.

In the printer 1, the near end of the remaining amount of ink in the ink reservoir 66 is detected as described above. This makes it possible to detect the near end more accurately with a simple configuration.
The tip surface 72 of the prism unit 70 is provided in such a state that light passing through the prism unit 70 is incident at a detection angle θd smaller than the critical angle of total reflection at the boundary between the tip surface 72 and the ink. Therefore, in the state where the reflecting surface of the film 64 is separated from the front end surface 72 and the ink is in contact with the front end surface 72, most of the light from the incident portion 73 is from the front end surface 72 to the ink side (ink The amount of light emitted from the emission part 74 is reduced as much as possible. Thereby, the difference of the emitted light quantity from the output part 74 becomes large between the state where the reflecting surface is separated from the distal end surface 72 and the state where the reflecting surface is close thereto, and the detection accuracy can be further improved.
Further, since the region of the reflecting surface of the film 64 that is in contact with the front end surface 72 is mirror-finished, the light from the incident portion 73 is more reflected when the mirror-finished region is in contact with the front end surface 72. It becomes easy to reflect, and the emitted light quantity from the output part 74 can be increased as much as possible. Therefore, the difference in the amount of light emitted from the light emitting portion 74 between the state in which the reflecting surface of the film 64 is separated from the front end surface 72 and the state in which the film 64 is close to the front surface 72 is further increased, and the detection accuracy can be further improved.

  In the above, the example in which the near end is detected based on the amount of light emitted from the light emitting portion 74 which is different between the separated state and the contact state of the film 64 (reflecting surface) with respect to the front end surface 72 has been described. It is also possible to adopt a configuration in which the numerical value of the remaining amount of ink in the ink reservoir 66 is obtained on the basis of the change in the amount of emitted light from the time when the reflecting surface comes close to the tip surface 72 to some extent and comes into contact. That is, it is possible to obtain a remaining amount of ink corresponding to the amount of light emitted from the light emitting portion 74 with reference to a table representing the relationship between the level of the light reception signal of the light receiving element 56 and the remaining amount of ink.

  Next, a second embodiment of the present invention will be described. 7A and 7B are views for explaining the configuration of the ink cartridge 77 according to the second embodiment. FIG. 7A is a cross-sectional view showing the internal configuration, FIG. 7B is a cross-sectional view taken along line XX in FIG. FIG. 3 is a view taken along line YY in (a). In FIG. 4B, the case 78 and the ink outlet 81 are not shown for convenience. The ink cartridge 77 is disposed in a case 78, a bag-shaped ink storage portion 80 that is disposed inside the case 78 and partitioned as an ink storage chamber 79, and the ink storage chamber 79. The ink outlet 81 that can lead out the ink to the outside, and the substantially U-shaped prism portion 83 (mainly attached to the attachment member 82 together with the ink outlet 81) and mostly contained in the ink storage chamber 79. It corresponds to a kind of optical waveguide in the invention).

  The ink reservoir 80 is formed in a bag shape by a flexible film 84, and a mounting member 82 is welded in a liquid-tight state on one side (left side in FIG. 7). In the ink storage portion 80, two surfaces facing each other are configured as a first flexible surface 84a and a second flexible surface 84b, respectively, and the directions in which the flexible surfaces 84a and 84b approach each other as the ink decreases. It is configured to bend toward the prism portion 83 side. The film 84 is configured by laminating polypropylene, a gas barrier layer, nylon or the like, like the film 64 in the first embodiment, and the surface facing the prism portion 83 is mirror-finished by laminating a metal foil or the like. It is a reflected surface.

  FIG. 8 is a diagram showing the configuration of the prism portion 83 in the present embodiment, where (a) is a plan view, (b) is a front view, (c) is a right side view, and (d) is a left side view. It is. The prism portion 83 includes a first waveguide 83a in which an incident portion 85 into which light from the light emitting element 55 (see FIGS. 9 and 10) is incident on one end side (left side in the figure), and a light receiving element on the other end side. 56 (see FIGS. 9 and 10), the second waveguide 83b in which the emission part 86 capable of emitting the light that has passed through the prism part 83 is formed, and these waveguides 83a and 83b are connected to the incident part 85. And a connecting waveguide 87 connected in series on the side opposite to the emitting portion 86 is formed in a substantially U shape.

  Similar to the prism portion 70 of the first embodiment, the prism portion 83 is made of a light-transmitting polycarbonate rod having a rectangular cross section, and is arranged in the ink storage portion 80 in the first state. The first reflection region 88 facing the flexible surface 84a and the second reflection region 89 facing the second flexible surface 84b are connected from the incident portion 85 except for the detection portions (detection portions 90a and 90b) described below. It is formed through the waveguide 87 to the emission part 86. That is, in the present embodiment, the upper surface of the prism portion 83 is the first reflection region 88 and the lower surface is the second reflection region 89. The prism portion 83 is mirror-finished by vapor deposition or sputtering of a metal film such as aluminum except for the incidence portion 85, the emission portion 86, and the detection portion (hatched portion in FIG. 8). The mirror-finished portion of the metal film is formed to have a thickness equal to or greater than the wavelength of light or infrared, specifically, a thickness equal to or greater than 1 μm.

  As shown in FIG. 8C, the incident portion 85 has an inclined surface having an angle of 45 ° with respect to the first reflection region 88, and the light emitted from the light emitting element 55 is the inclined surface. It is made to enter perpendicularly to. That is, the light emitted from the light emitting element 55 is incident on the first waveguide 83a in parallel with the axial direction of the first waveguide 83a in plan view, as indicated by an arrow in FIG. In the up-and-down direction (the bending direction of the flexible surfaces 84a and 84b), the light is incident on the first reflection region 88 at an oblique angle, specifically, at an incident angle of approximately 45 ° (θ). The light that has entered the first reflection region 88 from the incident portion 85 is reflected toward the second reflection region 89 at a reflection angle of approximately 45 °. That is, the prism unit 83 in the present embodiment is configured such that the light incident from the incident unit 85 is repeatedly incident and reflected (hereinafter referred to as incident / reflected) in the first reflection region 88 and the second reflection region 89. It is configured to travel inside.

  The connection waveguide 87 is formed in a trapezoidal shape in plan view, and the first inclined surface 87a has an angle of 45 ° with respect to the axial direction of the first waveguide 83a and the axial direction (longitudinal direction) of the connection waveguide 87. And a second inclined surface 87 b having an angle of 45 ° with respect to the axial direction of the second waveguide 83 b and the axial direction of the connecting waveguide 87. The first inclined surface 87a is configured to be able to reflect light from the incident surface 85 side to the second inclined surface 87b side, and the second inclined surface 87b can reflect light from the first inclined surface 87a side to the emitting portion 86 side. It is configured. Further, on the upper and lower surfaces of the connecting waveguide 87, a first detection unit 90a and a second detection unit 90b, which are transmissive surfaces that are not mirror-finished, are formed. In other words, the first detection unit 90a is provided in the middle of the first reflection region 88, the second detection unit 90b is provided in the middle of the second reflection region 89, and the first detection unit 90a is provided with the second reflection region. The light from the region 89 side and the second detector 90b are configured such that the light from the first reflection region 88 side is incident at least once at an incident angle of approximately 45 °.

In the prism portion 83, the connecting waveguide 87 is positioned at a substantially central portion in the ink storage chamber 79, and the first detection portion 90a and the second detection portion 90b are the first flexible surface 84a and the second flexible surface, respectively. The incident portion 85 and the emission portion 86 are fixed to the ink storage portion 66 in a state facing the 84b and located outside the ink storage portion 80 (outside the ink cartridge 77).
7A to 7C show an example in which the prism portion 83 is fixed so that the incident portion 85 and the emission portion 86 are located on the opposite side of the attachment member 82 from the ink outlet 81. As shown in FIG. 7D, the prism portion 83 can be fixed in a state where the ink outlet 81 is located between the incident portion 85 and the emission portion 86.

  As described above, when the light emitted from the light emitting element 55 of the optical sensor 37 is incident from the incident portion 85 of the prism portion 83, the light is incident and reflected at an angle of approximately 45 ° alternately at the reflection regions 88 and 89. Since the light travels in the prism portion 83 repeatedly, the light enters the detection portions 90a and 90b provided in the middle of the reflection regions 88 and 89 at an angle of approximately 45 °. That is, it can be said that the detection units 90a and 90b are configured with a surface having a detection angle θd = θ = 45 ° smaller than the critical angle of total reflection with respect to the ink with respect to the light path from the incident unit 85.

  And in this embodiment, it changes according to the separation state or contact state of the 1st flexible surface 84a with respect to the 1st detection part 90a, and the separation state or contact state of the 1st flexible surface 84b with respect to the 1st detection part 90b. The near end of the remaining amount of ink in the ink storing unit 80 is detected based on the amount of light emitted from the emitting unit 86. Hereinafter, detection of near-end in the present embodiment will be described.

  FIG. 9 is a diagram illustrating a state in which the remaining amount of ink in the ink storage unit 80 (ink storage chamber 79) is relatively large and both the flexible surfaces 84a and 84b are separated from the detection units 90a and 90b of the prism unit 83. (A) is a cross-sectional view of the ink reservoir 80, and (b) is a plan view of the prism portion 83. The light emitted from the light emitting element 55 of the optical sensor 37 and incident from the incident portion 85 of the prism portion 83 is approximately 45 °, that is, the first reflection while alternately repeating the incident / reflection at the detection angle θd in the reflection areas 88 and 89. The light travels inside the waveguide 83a and enters the first inclined surface 87a. Since the first inclined surface 87a is an inclined surface of 45 ° with respect to the axial direction of the first waveguide 83a and the axial direction of the coupling waveguide 87, the light incident on the first inclined surface 87a is not incident on this surface. Reflected to change the traveling direction by 90 ° toward the second slope 87b in plan view. In the present embodiment, the light reflected by the first slope 87a first enters the second detection unit 90b at an incident angle of the detection angle θd. In the state shown in FIG. 9, since the ink is in contact with the detection units 90a and 90b and the critical angle at the boundary between the detection units 90a and 90b and the ink is larger than the detection angle θd, the second detection unit 90b Most of the incident light is transmitted to the ink storage chamber 79 side (second flexible surface 84b side). Even if there is light reflected by the second detection unit 90b, this light then enters the first detection unit 90a, and most of the light is transmitted to the ink storage chamber 79 side (first flexible surface 84a side). To do. Therefore, in the state shown in FIG. The controller 42 does not determine near end in this state.

  FIG. 10 shows a state in which the remaining amount of ink in the ink storage chamber 65 is reduced to some extent, the first flexible surface 84a is separated from the first detection unit 90a, and the second flexible surface 84b is in contact with the second detection unit 90b. (A) is a cross-sectional view of the ink reservoir 80, and (b) is a plan view of the prism portion 83. In this state, since the reflecting surface of the second flexible surface 84b is in contact with the second detecting unit 90b, most of the light incident on the second detecting unit 90b is reflected by the reflecting surface of the second flexible surface 84b. The light is reflected and enters the first detection unit 90a. However, in this state, since the ink is in contact with the first detection unit 90a, most of the light incident on the first detection unit 90a is on the ink storage chamber 79 side (first flexible surface 84a side). Transparent to. Therefore, the amount of light emitted from the emitting portion 86 in the state shown in FIG. 10 is very small even if it slightly increases from the state shown in FIG. 9, and the control portion 42 does not determine that the light is emitted in this state.

  10 illustrates the case where the second flexible surface 84b first contacts the second detection unit 90b in FIG. 10, but the first flexible surface 84a first contacts the first detection unit 90a and the second possible surface. A case where the flexure surface 84a is separated from the first detection unit 90b is also conceivable. Even in this case, since most of the light incident on the second detection unit 90b is transmitted to the ink storage chamber 79 side, the amount of light emitted from the emission unit 86 is very small and is not determined to be near-end.

  FIG. 11 is a diagram illustrating a state where the remaining amount of ink in the ink storage chamber 79 is small and the flexible surfaces 84a and 84b are in contact with the detection units 90a and 90b, respectively. FIG. 6B is a plan view of the prism portion 83. In this state, most of the light incident on the detectors 90a and 90b is reflected by the reflecting surfaces of the flexible surfaces 84a and 84b, and then enters the second inclined surface 87b. Since the second inclined surface 87b is an inclined surface of 45 ° with respect to the axial direction of the second waveguide 83b and the axial direction of the connecting waveguide 87, the light incident on the second inclined surface 87b is reflected to the emitting portion 86 side. Then, the traveling direction is changed by 90 ° in plan view. This light travels through the second waveguide 83b while being alternately reflected and reflected at the detection angle θd by the reflection regions 88 and 89, and is emitted from the emitting portion 86. For this reason, the amount of light emitted from the emitting portion 86 increases sharply as compared with the states of FIGS. 9 and 10, and a light receiving signal corresponding to the amount of received light is output from the light receiving element 56 to the control portion 42. Then, the control unit 42 determines that the remaining amount of ink in the ink storage unit 80 (ink storage chamber 79) has become near-end when the light reception signal from the light receiving element 56 exceeds a predetermined threshold.

  In the second embodiment, even if either one of the flexible surfaces 84a and 84b contacts the detection units 90a and 90b, the amount of light emitted from the emission unit 86 in a state where the other is separated from the detection units 90a and 90b. Therefore, the ink remaining in the ink storage section 80 is not near-end as in the state shown in FIG. It is possible to prevent the determined malfunction.

  In the second embodiment, the detection units 90a and 90b are provided in both the first reflection region 88 and the second reflection region 89, respectively. However, the detection unit is provided in either one of the reflection regions 88 and 89. It can also be set as the structure which provides. For example, a configuration in which a detection unit is provided only in the first reflection region 88 and a detection unit is not provided in the second reflection region 89 is possible. In this case, since the amount of light emitted from the light emitting portion 86 changes according to the change in the position (distance) of the first flexible surface 84a with respect to the detection portion of the first reflective region 88, the ink storage portion is based on the change in the amount of light emitted. The remaining amount of ink in 80 can be detected.

By the way, the present invention is not limited to the above-described embodiment, and various modifications can be made based on the description of the scope of claims.
For example, regarding the detection angle θd, in the above-described embodiment, an example in which the detection angle is set to 45 ° is shown. However, the detection angle is not limited to this, and the detection unit (tip surface 72, detection units 90a and 90b), ink, Any angle can be adopted as long as the angle is equal to or greater than the critical angle at the boundary portion of the light source and the light from the incident portion side can be reflected to the emission portion side with the flexible surface (reflecting surface) in contact with the detection portion. be able to.

  Regarding the light emitting element, in each of the above-described embodiments, an example in which the semiconductor laser is configured to emit straight light has been described. However, the present invention is not limited thereto. You can also In this case, in the prism part, it is desirable that the part excluding the incident part, the emission part, and the detection part is mirror-finished. In short, even if the light incident from the incident portion of the prism portion is diffused light, the light amount from the emitting portion may be changed depending on the separation state and contact state of the flexible surface with respect to the detection portion.

Regarding the shape of the prism portion, the first embodiment exemplifies the prism portion 70 formed in a substantially V shape by the rectangular columnar first waveguide 71a and the second waveguide 71b intersecting each other at 90 °. Not limited to this. For example, as shown in FIG. 12, an incident part 73 ′, an emission part 74 ′, and a tip surface 72 ′ (detection part) having an angle of 45 ° with respect to the incidence part 73 ′ and the emission part 74 ′ are provided. Other shapes such as the prism portion 70 ′ having a substantially hexagonal cross section may be used.
Further, in the second embodiment, the prism portion 83 having a substantially U-shape in which the incident portion 86 and the emission portion 87 are disposed on the same side and having a quadrangular cross section is illustrated, but the present invention is not limited thereto. For example, as shown in FIG. 13, it is a straight rod-shaped waveguide having an incident portion 86 ′ on one end side, an emitting portion 87 ′ on the other end side, and a detecting portion 90 ′ on the way. May be.
Furthermore, in the above-described embodiment, the prism section 83 having a quadrangular cross section is exemplified, but a circular section having a circular cross section may be employed.

  In the above embodiment, the so-called longitudinal vibration mode piezoelectric vibrator 22 is exemplified as the pressure generating element of the present invention, but the present invention is not limited to this. For example, a piezoelectric vibrator that can vibrate in the electric field direction (the stacking direction of the piezoelectric body and the internal electrode) may be used. In addition, the nozzles are not limited to being unitized, but may be provided for each pressure chamber 28 as in a so-called flexural vibration mode piezoelectric vibrator. Further, not only the piezoelectric vibrator but also other pressure generating elements such as a heating element can be used.

  The present invention can also be applied to a liquid ejecting apparatus other than the printer as long as a liquid storage member that stores liquid is mounted. For example, it can be applied to a display manufacturing apparatus, an electrode manufacturing apparatus, a chip manufacturing apparatus, a micropipette, and the like.

FIG. 2 is a plan view illustrating a configuration of a printer. FIG. 3 is a cross-sectional view of a main part for explaining the configuration of a recording head. 2 is a block diagram illustrating an electrical configuration of a printer. FIG. 2A and 2B are diagrams illustrating a configuration of an ink cartridge, in which FIG. 1A is a plan view, FIG. 1B is a cross-sectional view taken along line AA in FIG. 1A, and FIG. It is a figure which shows the state which the ink remaining amount in an ink storage chamber was comparatively large, and the reflective surface of the film was separated from the front end surface of the prism part. It is a figure which shows the state which the ink remaining amount in an ink storage chamber became small and the film contacted the front end surface. It is a figure explaining the structure of the ink cartridge in 2nd Embodiment, (a) is sectional drawing which shows an internal structure, (b) is the XX sectional view taken on the line in (a), (c) is in (a). It is a YY line arrow directional view. It is a figure which shows the structure of the prism part in 2nd Embodiment, (a) is a top view, (b) is a front view, (c) is a right view, (d) is a left view. FIG. 6 is a diagram illustrating a state in which the remaining amount of ink in the ink storage unit is relatively large, and both the first flexible surface and the second flexible surface are separated from the first detection unit and the second detection unit of the prism unit; a) is a cross-sectional view of the ink reservoir, and FIG. FIG. 6 is a diagram illustrating a state in which the remaining amount of ink in the ink storage chamber is reduced to some extent, the first flexible surface is separated from the first detection unit, and the second flexible surface is in contact with the second detection unit; Sectional drawing of an ink storage part, (b) is a top view of a prism part. It is a figure which shows the state which the ink remaining amount in an ink storage chamber became small, and the 1st flexible surface and the 2nd flexible surface contacted the 1st detection part and the 2nd detection part, respectively. Is a cross-sectional view of the ink reservoir, and (b) is a plan view of the prism portion. It is a figure which shows the modification of the prism part in 1st Embodiment. It is a figure which shows the modification of the prism part in 2nd Embodiment.

Explanation of symbols

  1 printer, 2 frame, 3 platen, 4 guide rod, 5 carriage, 6 pulse motor, 7 drive pulley, 8 idle pulley, 9 timing belt, 10 recording head, 12 ink cartridge, 13 cartridge holder, 14 air tube, 15 Air pump, 16 ink supply tube, 19 case, 20 transducer unit, 21 channel unit, 22 piezoelectric transducer, 23 channel forming substrate, 24 nozzle plate, 25 elastic plate, 26 reservoir, 27 ink supply port, 28 pressure Chamber, 29 Nozzle communication port, 30 Nozzle opening, 31 Diaphragm part, 32 Island part, 33 Compliance part, 35 Printer controller, 36 Print engine, 37 Photo sensor, 39 External interface, 40 RAM, 41 ROM, 42 control Part, 43 oscillation circuit, 44 drive signal generation circuit, 45 internal interface, 47 paper feed motor, 49 shift register, 50 latch circuit, 51 level shifter, 52 switch circuit, 55 light emitting element, 56 light receiving element, 59 case, 60 lid member , 61 Case body, 62 Enclosure wall, 63 Ink outlet, 64 Film, 65 Ink storage chamber, 66 Ink storage section, 67 Air chamber, 68 Air supply section, 70 Prism section, 71 Waveguide, 72 Front end surface, 73 Incident Part, 74 emitting part, 77 ink cartridge, 78 case, 79 ink storing chamber, 80 ink storing part, 81 ink outlet, 82 mounting member, 83 prism part, 84 film, 85 incident part, 86 emitting part, 87 connection guide Waveguide, 88 1st reflection area, 89 2nd reflection area, 90 detector

Claims (12)

A liquid storage section for storing liquid, and a liquid outlet section for discharging liquid in the liquid storage section,
At least a part of the liquid storage part is configured as a flexible surface that bends as the liquid decreases, and is a liquid storage member having at least a part of the flexible surface as a reflection surface,
Provided with an optical waveguide that allows light from the light emitting element to be incident from the incident part and to be emitted from the emitting part toward the light receiving element through the inside,
The optical waveguide has a detection part in the middle capable of emitting light passing therethrough toward the reflecting surface,
The detection unit is arranged at a position where the reflection surface gradually approaches when the flexible surface bends as the liquid in the liquid storage unit decreases, and the emission unit receives reflected light from the adjacent reflection surface. To be passed through,
A liquid storage member configured to be able to detect a remaining amount of liquid in the liquid storage unit based on an emitted light amount of the emission unit that changes with a change in a distance between the detection unit and the reflection surface.   The detection unit is provided in a state in which light passing through the optical waveguide is incident at a detection angle smaller than a critical angle of total reflection at a boundary between the detection unit and the liquid. Item 2. A liquid storage member according to Item 1.   The liquid storage member according to claim 2, wherein the detection angle is set to approximately 45 °. The surface facing the flexible surface in the liquid storage portion is configured as a base portion made of a hard member,
The liquid storage member according to claim 1, wherein the optical waveguide is fixed to the base portion.   5. The liquid storage member according to claim 1, wherein at least a region of the reflecting surface that comes into contact with the detection unit is mirror-finished. Two surfaces facing each other of the liquid reservoir are configured as a first flexible surface and a second flexible surface, respectively.
In the optical waveguide, a first reflection region facing the first flexible surface and a second reflection region facing the second flexible surface are provided from the incident portion except the detection portion to the emission portion. The light from the light emitting element is obliquely incident on the first reflection region from the incident portion, and is directed toward the emission portion while repeating incidence and reflection alternately in the first reflection region and the second reflection region. Configured to be able to proceed inside,
The detection unit is provided in the middle of the first reflection region,
6. The liquid according to claim 1, wherein the amount of light emitted from the emission unit is changed in accordance with a change in the distance between the detection unit and the first flexible surface. Storage member. Two surfaces facing each other of the liquid reservoir are configured as a first flexible surface and a second flexible surface, respectively.
In the optical waveguide, a first reflection region facing the first flexible surface and a second reflection region facing the second flexible surface are provided from the incident portion except the detection portion to the emission portion. The light from the light emitting element is obliquely incident on the first reflection region from the incident portion, and is directed toward the emission portion while repeating incidence and reflection alternately in the first reflection region and the second reflection region. Configured to be able to proceed inside,
A first detector is provided in the middle of the first reflective region, and a second detector is provided in the middle of the second reflective region,
Depending on the separation state or contact state of the first flexible surface with respect to the first detection unit and the separation state or contact state of the second flexible surface with respect to the second detection unit, the amount of light emitted from the emission unit is The liquid storage member according to claim 1, wherein the liquid storage member is configured to change.   8. The optical waveguide according to claim 6, wherein the first reflection area other than the first detection part and the second reflection area other than the second detection part are mirror-finished. The liquid storage member described.   The liquid storage member according to claim 1, wherein the liquid is stored in a liquid-tight manner. A light emitting element that emits light toward the incident part of the liquid storage member according to any one of claims 1 to 9, and a light receiving element that receives light from the emission part of the liquid storage member,
A liquid amount detection device characterized in that the remaining amount of liquid in the liquid reservoir can be detected according to the amount of light received by the light receiving element.   The liquid amount detection device according to claim 10, wherein a state in which the amount of remaining liquid in the liquid storage portion becomes small can be detected according to the amount of light received by the light receiving element. The liquid storage member according to any one of claims 1 to 9 is mounted,
A liquid ejecting apparatus comprising: a liquid ejecting head capable of ejecting the liquid in the liquid storage member as droplets; and the liquid amount detecting device according to claim 10 or 11.

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