JP4923931B2 - Detection device - Google Patents

Description

  The present invention relates to a detection device that detects a state of an ink cartridge mounted on an ink jet recording apparatus.

  An ink jet recording apparatus records an image on a recording paper (recording medium) by selectively ejecting ink supplied to a recording head from a nozzle. In this ink jet recording apparatus, an ink cartridge for storing ink is detachably attached to the apparatus main body. The recording head is provided with a sub tank that stores ink supplied from the ink cartridge. The ink in the sub tank is ejected from the nozzles by an ejection mechanism such as an actuator such as an electrostrictive element or a heating element.

  The ink stored in the ink cartridge gradually decreases as it is used for recording an image by the recording head. If the amount of ink in the ink cartridge is insufficient, air may be sent to the recording head and ink may not be ejected. For this reason, a conventional ink jet recording apparatus is provided with a sensor for detecting the remaining amount of ink in order to prompt the user to replace an ink cartridge having an insufficient ink amount (see, for example, Patent Document 1).

  In the ink jet recording apparatus described in Patent Document 1, a transmissive optical sensor is provided in the apparatus main body. An ink cartridge attached to the apparatus main body has a built-in arm that is pivotally supported. This arm is provided with a light-shielding plate that does not transmit light at one end, and a hollow float at the other end. For this reason, the arm is swung by the buoyancy exerted by the ink on the float. The ink cartridge has a protrusion. The protruding portion is disposed in a space between the light emitting portion and the light receiving portion of the optical sensor when the ink cartridge is attached to the apparatus main body. In a state where the entire float is located in the ink due to the large amount of ink, the posture in which the float floats and the light shielding plate moves to the protruding portion is maintained. For this reason, when the amount of ink is large, light emitted from the light emitting unit to the light receiving unit is blocked. When the ink is reduced and a part of the float is exposed from the ink surface, the buoyancy acting on the float is reduced and the float is lowered. Along with this, the light that is emitted from the light emitting portion when the light shielding plate is retracted from the protruding portion is received by the light receiving portion. Thereby, it is possible to detect a state in which the remaining amount of ink in the ink cartridge is low.

JP 2005-254734 A

  By the way, bubbles are generated in the process of consuming ink. When the bubbles adhere to the moving body or the buoyancy body, buoyancy greater than the buoyancy acting on the buoyancy body acts on the movement body. For this reason, it has not been possible to accurately detect that the ink amount has reached the predetermined amount, and as a result, there has been a risk of ink ejection failure.

  SUMMARY An advantage of some aspects of the invention is that it provides a detection device that can accurately determine whether or not the amount of ink in an ink cartridge is a predetermined amount.

(1) A detection device according to the present invention includes an ink cartridge having an ink tank for storing ink, an arm member provided swingably on the ink tank, a detector provided on the arm member, A sensor for detecting a detector; a determination unit for determining the ink amount based on a detection result of the sensor; and a movable member for swinging the arm member. The movable member moves between a first position where the detector can be detected and a second position where the detector cannot be detected. The determination unit determines an operation state of the movable member based on a detection result of the sensor.

  The detection apparatus of the present invention is mounted on an ink jet recording apparatus. The ink cartridge is detachably attached to the detection device and has an ink tank. The ink tank stores ink. The arm member is swingably provided in the ink tank. The arm member swings by increasing or decreasing the ink in the ink tank. This arm member is provided with a detector. The detector moves when the arm member is swung. A sensor is provided in the apparatus main body. In a state where the ink cartridge is mounted on the apparatus main body, the detector at a predetermined position is detected by this sensor. The detector moves from the predetermined position when the ink is reduced to a predetermined amount. Therefore, it is detected by the sensor whether or not the detector is at a predetermined position, and the determination unit determines whether or not the ink amount is a predetermined amount based on the detection result.

  Bubbles are generated in the process where the ink stored in the ink tank is consumed. When the bubbles adhere to the arm member, normal swinging of the arm member is prevented. For this reason, the detection of the ink amount may be delayed. However, the detection device of the present invention is provided with a movable member. This movable member swings the arm member. Thereby, the bubble adhering to the arm member is shaken off from the arm member.

  The movable member moves between the first position and the second position. When the movable member is in the first position, the detector is detected by the sensor. In the state where the movable member is in the second position, the detector is not detected by the sensor. For this reason, the operation state of the movable member is determined based on the detection result of the sensor when the movable member is moved.

  (2) The specific gravity of the ink stored in the ink tank is preferably heavier than the average specific gravity of the arm member.

  With the above configuration, the arm member receives buoyancy from the ink in a state where the arm member is swingably provided. For this reason, the arm member is swung by the buoyancy received from the ink.

  (3) The ink cartridge includes a piston that reciprocates in a cylinder to supply air to an air layer formed in the ink tank or to suck air from the air layer. The slide member provided in the piston may be sufficient.

  The ink cartridge is provided with a piston. The piston reciprocates in a cylinder provided in the ink cartridge. The ink tank contains air together with ink. For this reason, an air layer is formed in the ink tank. When the piston reciprocates, air is supplied to the air layer or air is sucked from the air layer. The ink tank is connected to a recording head of the ink jet recording apparatus. In this state, when the piston is moved in a direction in which air is sucked from the air layer, the ink stored in the recording head flows into the ink tank. When the piston is moved in the direction in which air is supplied to the air layer, the ink in the ink tank is pushed out toward the recording head. That is, ink is supplied from the ink tank to the recording head by the reciprocation of the piston. The movable member is a slide member provided on the piston. In other words, the movable member slides in conjunction with the reciprocating motion of the piston.

  (4) The piston may be provided with a rod extending outside the cylinder, and the piston may reciprocate by a driving force applied to the rod.

  With this configuration, since the piston is reciprocated with a simple configuration, the operation of the movable member is easily performed.

(5) A detection unit arranged in the detection region of the sensor when the ink cartridge is mounted on the apparatus main body, and the determination unit determines a mounting state of the ink cartridge based on a detection result of the sensor. You may do.

  The ink tank is provided with a detection unit. The detector is configured such that the detector can move. Before the ink cartridge is attached to the apparatus main body, the detection unit is not arranged in the detection area of the sensor. For this reason, the detector is not detected by the sensor. When the ink cartridge is attached to the apparatus main body, the detection unit is disposed in the detection region of the sensor. For this reason, the detector located in the detection unit is detected by the sensor. That is, the mounting state of the ink cartridge is determined based on the detection result of the sensor.

  According to the detection device of the present invention, the arm member is swung by the movable member, so that bubbles attached to the arm member are swung away from the arm member. Therefore, it is possible to accurately determine whether or not the amount of ink in the ink tank is a predetermined amount without being affected by bubbles generated in the ink tank.

  Embodiments of the present invention will be described below with reference to the drawings as appropriate. Note that the following embodiment is merely an example of the present invention, and it is needless to say that the embodiment can be appropriately changed without departing from the gist of the present invention.

  First, a schematic configuration and operation of an inkjet recording apparatus 10 according to an embodiment of a detection apparatus of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a schematic cross-sectional view showing an internal mechanism of the ink jet recording apparatus 10, and FIG. 2 is an enlarged view of a main part showing in detail the recording unit 14 in FIG. 2A shows a state in which the opening 42 of the valve 37 is closed, and FIG. 2B shows a state in which the opening 42 of the valve 37 is opened.

  The ink jet recording apparatus 10 records a color image or a monochrome image on a recording sheet (an example of a recording medium). For recording this image, five colors of ink are used. Specifically, the five color inks are cyan (C), magenta (M), yellow (Y), photo black (PBk), which is a dye ink, and black (Bk), which is a pigment ink. As shown in FIG. 1, the ink jet recording apparatus 10 roughly includes a paper feeding device 12, a transport device 13, a recording unit 14, and an ink supply device 11. The ink cartridge 50 is attached to the ink supply device 11. A paper feed tray 16 is provided on the bottom surface of the ink jet recording apparatus 10. The recording paper loaded on the paper feed tray 16 is supplied to the transport path 18 by the paper feed device 12.

  The conveyance path 18 is formed in a U-shape that is substantially horizontal in a sectional view. The transport device 13 is disposed in the transport path 18. The transport device 13 includes a transport roller pair 13A and a paper discharge roller pair 13B. The pair of transport rollers 13A is provided on the upstream side in the transport direction from the recording unit 14 (on the right side in FIG. 1). The paper discharge roller pair 13B is provided on the downstream side in the transport direction from the recording unit 14 (left side in FIG. 1).

  The recording paper supplied to the conveyance path 18 is conveyed toward the platen 19 by the conveyance roller pair 13A. A recording unit 14 is disposed above the platen 19. The recording unit 14 records an image on a recording sheet that passes over the platen 19. When the leading edge of the recording paper reaches the paper discharge roller pair 13B, the paper discharge roller pair 13B pinches the leading edge of the recording paper and starts conveying the recording paper. Until the trailing edge of the recording sheet passes the conveyance roller pair 13A, the recording sheet is conveyed by both the conveyance roller pair 13A and the discharge roller pair 13B. After the trailing edge of the recording sheet passes through the conveyance roller pair 13A, the recording sheet is conveyed only by the discharge roller pair 13B. A paper discharge tray 17 is provided on the most downstream side of the transport path 18. The recording sheet on which the image is recorded is discharged to the discharge tray 17 by the discharge roller pair 13B.

  The recording unit 14 includes a carriage 30 that also serves as a housing, a sub tank 21, a head control board 27, and a recording head 26. The carriage 30 is supported by a support rail (not shown) so as to be capable of reciprocating in a direction perpendicular to the paper surface of FIG. The sub tank 21, the head control board 27, and the recording head 26 are accommodated in the carriage 30. The sub tank 21 stores ink supplied to the recording head 26. The sub tank 21 is provided corresponding to the five colors of ink used in the inkjet recording apparatus 10. Therefore, in the present embodiment, the five sub tanks 21 are provided in the carriage 30.

  The recording head 26 includes a nozzle 28. The recording head 26 selectively ejects ink from the nozzles 28 toward the recording paper moving on the platen 19. As a result, an image corresponding to the image signal input to the head control board 27 is recorded on the recording paper. The inkjet recording apparatus 10 is provided with a control unit 230 (see FIG. 11) that controls the apparatus in an integrated manner. The image signal is output from the control unit 230 and input to the head control board 27.

  As shown in FIG. 2, a tube joint 33 is provided on the side surface of the carriage 30. An ink tube 32 is connected to the tube joint 33. The tube joint 33 and the ink tube 32 are provided corresponding to the five colors of ink used in the inkjet recording apparatus 10. Therefore, in the present embodiment, five tube joints 33 and five ink tubes 32 are provided. Inside the carriage 30, a flow path 34 extending from the tube joint 33 to the bottom surface of the sub tank 21 is formed.

  The carriage 30 is provided with a valve 37, and the opening 42 is opened and closed by the valve 37. As shown in FIG. 2, the valve 37 is a piston-type valve including a cylinder 39 communicating with the sub tank 21, a coil spring 41, and a piston 40. The coil spring 41 is accommodated in the cylinder 39. The piston 40 is accommodated in the cylinder 39 with the coil spring 41 contracted. Therefore, the piston 40 is always urged by the coil spring 41 in one direction (downward with respect to the paper surface of FIG. 2). The piston 40 is provided with a rod 43 to which an external force is transmitted. The rod 43 is inserted through an opening 42 provided in the cylinder 39 and extends to the outside. The opening 42 is closed by the piston 40 when no external force is transmitted to the rod 43 (see FIG. 2A).

  When an external force is transmitted from the rod 43 to the piston 40, the piston 40 moves in the cylinder 39 against the urging force of the coil spring 41. Specifically, in FIG. 2, when the rod 43 is pressed upward from below, the piston 40 is pushed up against the biasing force of the coil spring 41 and the opening 42 is opened (see FIG. 2B). . Thereby, the inside of the sub tank 21 and the atmosphere communicate with each other through the opening 42 and the cylinder 39. In other words, the inside of the sub tank 21 communicates with the atmosphere. The opening 42 is opened when ink flows in and out between the ink cartridge 50 (see FIG. 1) and the sub tank 21 through the ink tube 32. On the other hand, when the ink jet recording apparatus 10 is not operating, that is, in a so-called standby state, the opening 42 is closed in order to prevent ink evaporation.

  As shown in FIG. 1, the ink supply device 11 includes a cartridge mounting part 200, an ink cartridge 50, an ink tube 32, an optical sensor 203 (an example of the sensor of the present invention), and a sub tank 21. The ink cartridge 50 is mounted on the cartridge mounting unit 200 (see FIG. 7). The ink cartridge 50 is configured to be detachable from the cartridge mounting portion 200. The ink cartridge 50 has a main tank 70 (corresponding to the ink tank of the present invention). The main tank 70 and the sub tank 21 are both containers for storing ink. The main tank 70 stores ink supplied to the sub tank 21. The main tank 70 and the sub tank 21 are connected by an ink tube 32. One ink tube 32 is provided between the main tank 70 and the sub tank 21 for each type of ink used in the inkjet recording apparatus 10. That is, the ink tube 32 does not circulate ink between the main tank 70 and the sub tank 21. Through the ink tube 32, the ink flows in both directions between the main tank 70 and the sub tank 21. The ink tube 32 is made of a synthetic resin transparent member and has flexibility. Therefore, when the carriage 30 reciprocates during image recording, the ink tube 32 follows the carriage 30. The optical sensor 203 detects the state of the ink cartridge. Based on the detection result of the optical sensor 203, determination processing by the control unit 230 (corresponding to the determination unit of the present invention) is performed. Specifically, this determination processing includes determination of the mounting state of the ink cartridge 50, determination of the ink amount of the ink cartridge 50, and determination of the operating state of the slide member 108 (see FIG. 4). Note that these determination processes will be described in detail later.

  In the present embodiment, as described above, since the ink supply device 11 is provided in the ink jet recording apparatus 10, ink can be circulated bidirectionally between the main tank 70 and the sub tank 21. Accordingly, when ink is supplied from the sub tank 21 to the main tank 70 by the ink supply device 11, bubbles generated in the sub tank 21 and the ink tube 32 are separated from the ink in the main tank 70. Further, by flowing ink from the main tank 70 into the sub tank 21, the ink in the sub tank 21 is replaced with the ink stored in the main tank 70.

  Next, each element constituting the ink supply device 11 will be described in detail. First, an external configuration and an internal configuration of the ink cartridge 50 will be described with reference to FIGS. 3 and 4. FIG. 3 is a perspective view showing an external configuration of the ink cartridge 50. FIG. 4 is a longitudinal sectional view showing the internal structure of the ink cartridge 50.

  As shown in FIGS. 3 and 4, the ink cartridge 50 includes a case 52. Each element constituting the ink cartridge 50 is accommodated in the case 52. The case 52 is thin in the width direction (Y-axis direction in FIG. 3), is long in the height direction (vertical direction, Z-axis direction in FIG. 3), and the depth direction (X-axis direction in FIG. 3) is higher than the height direction. Is formed in a substantially longer rectangular parallelepiped shape. Accordingly, the appearance of the ink cartridge 50 has a substantially rectangular parallelepiped shape. The X-axis direction in FIG. 3 coincides with the mounting direction of the ink cartridge 50 with respect to the cartridge mounting unit 200 (see FIG. 7). In addition, a plane formed by the X axis and the Y axis in the drawing (hereinafter referred to as “XY plane”) is a horizontal plane. The ink cartridge 50 is mounted on the cartridge mounting unit 200 in the posture shown in FIG. 4, that is, the posture standing on the XY plane (see FIGS. 7 and 8).

  As shown in FIG. 3, the case 52 includes a first case member 53 and a second case member 54. The case 52 can be separated into a first case member 53 and a second case member 54 along the longitudinal direction of the ink cartridge 50 (X-axis direction and Z-axis direction in FIG. 3). The first case member 53 and the second case member 54 are formed in substantially the same shape. The first case member 53 and the second case member 54 are both made of synthetic resin and obtained by, for example, injection molding.

  The case 52 is provided with three openings 56, 57, and 67 as shown in FIG. The opening 56 is provided from the upper surface 59 of the case 52 to the back surface 60 (surface on the front side in the mounting direction of the ink cartridge 50). The opening 56 is formed by a notch 61 formed in each of the first case member 53 and the second case member 54. A cylinder 171 (see FIG. 3 and FIG. 4) described later is inserted through the opening 56. This cylinder 171 corresponds to the cylinder of the present invention. The opening 57 is provided in the lower part of the back surface 60 (see FIG. 4). The opening 57 is formed by a semicircular cutout (not shown) formed in each of the first case member 53 and the second case member 54. An ink supply valve 130 described later is provided in the opening 57, and a part of the ink supply valve 130 is exposed to the outside of the case 52. As shown in FIG. 3, the opening 67 is provided in the upper surface 59 so as to be long in the X-axis direction. The opening 67 is formed by a rectangular cutout 62 (see FIG. 3) formed in each of the first case member 53 and the second case member 54. From the opening 67, a detection unit 75 (see FIGS. 3 and 4) described later is exposed to the outside. The detector 75 constitutes a part of the upper surface of the main tank 70 (see FIG. 4).

  As shown in FIG. 4, a main tank 70, a pump 170, and an ink supply valve 130 are provided inside the case 52. In the present embodiment, the main tank 70, the pump 170, and the ink supply valve 130 are all made of synthetic resin.

  As shown in FIG. 4, the main tank 70 is substantially entirely covered with a case 52. Accordingly, the main tank 70 is thin in the width direction (Y-axis direction, the direction perpendicular to the paper surface of FIG. 4) corresponding to the case 52, long in the height direction (vertical direction, Z-axis direction), and in the depth direction ( It has a long shape in the mounting direction (X-axis direction). The main tank 70 stores ink supplied to the sub tank 21 (see FIG. 1). The main tank 70 includes a translucent frame 71 and a frame 72. A cylinder 171 described later is formed in the frame 72. The frames 71 and 72 are connected so that a part of the cylinder 171 is fitted into the frame 71 (see FIG. 4). Although not shown in the drawing, transparent films are welded to both sides of the frames 71 and 72. As a result, the first ink chamber 73 and the second ink chamber 63 are partitioned in the main tank 70.

  As shown in FIG. 4, the frame 71 is provided with an opening 77 above the back surface 65 of the frame 71. The opening 77 is for inserting a cylinder 171 (see FIG. 3) provided in the frame 72 into the first ink chamber 73, and is formed in a circular shape. By fitting the cylinder 171 into the opening 77, the frame 71 and the frame 72 are connected without a gap. For this reason, when a piston 181 (corresponding to a piston of the present invention) described later reciprocates in the cylinder 171, air is sucked from the first ink chamber 73 into the cylinder 171, or from the cylinder 171 to the first ink. Air is supplied into the chamber 73.

  As shown in FIG. 4, the frame 72 is provided with an opening 87 at a substantially central position on the back surface 85. The opening 87 flows out the ink stored in the main tank 70 to the outside and allows the ink to flow into the main tank 70 from the outside. The opening 87 is provided on the back side (the right side in FIG. 4) of the main tank 70 and is formed in a circular shape. An ink supply valve 130 (see FIGS. 3 and 4) is provided in the opening 87. The ink supply valve 130 is a valve for causing the ink stored in the first ink chamber 73 and the second ink chamber 63 to flow in and out. The ink supply valve 130 is attached to the frame 72 so as to close the opening 87. Thus, the ink supply valve 130 serves as a connection port for connecting the ink tube 32 (see FIGS. 1 and 2) to the second ink chamber 63. A needle-like ink extraction tube 149 (see FIG. 4) is provided at the tip of the ink tube 32 (see FIG. 1). By inserting the ink extraction tube 149 into the ink supply valve 130, the second ink chamber 63 is connected to the ink tube 32 while maintaining a sealed state from the outside. The opening 87 is closed by the ink supply valve 130 when the ink extraction tube 149 is pulled out from the ink supply valve 130. That is, the opening 87 is opened or closed by the ink supply valve 130.

  A hole 89 is provided in a lower portion of the frame 71 on the back side (right side in FIG. 4). The hole 89 communicates the first ink chamber 73 and the second ink chamber 63. A check valve 95 that opens and closes the hole 89 is disposed in the hole 89. The check valve 95 opens the hole 89 when the first ink chamber 73 becomes positive pressure with respect to the second ink chamber 63. The check valve 95 closes the hole 89 when the first ink chamber 73 becomes negative with respect to the second ink chamber 63.

  As shown in FIG. 4, the frame 72 is provided with openings 101 and 105 above the frame 72. The opening 101 is provided on the upper surface of the cylinder 171 formed by the frame 72 (see FIG. 4). The opening 101 is for opening the air in the first ink chamber 73 to the atmosphere. As will be described later, a piston 181 that reciprocates in the cylinder 171 is provided inside the cylinder 171. In a state where the piston 181 is located on the far side of the cylinder 171 from the opening 101 (for example, the state shown in FIG. 4), the flow path between the first ink chamber 73 and the opening 101 is blocked by the piston 181. For this reason, the air in the first ink chamber 73 is not released to the atmosphere. That is, the air in the first ink chamber 73 is sealed. In a state where the piston 181 is positioned outside the cylinder 171 with respect to the opening 101 (the state shown in FIG. 16), the flow path between the first ink chamber 73 and the opening 101 is opened. For this reason, the air in the first ink chamber 73 is released to the atmosphere through the inside of the cylinder 171 and the opening 101.

  The opening 105 communicates the second ink chamber 63 with the inside of the cylinder 171. The opening 105 is formed so as to penetrate from the upper surface of the second ink chamber 63 to the inside of the cylinder 171. The opening 105 is closed when the piston 181 is positioned immediately above the second ink chamber 63 (the state shown in FIG. 14). The second ink chamber 63 is opened to the atmosphere through the opening 105 when the piston 181 is located behind the opening 105 in the cylinder 171 (for example, the state shown in FIGS. 4 and 18). The second ink chamber 63 communicates with the first ink chamber 73 through the opening 105 when the piston 181 is positioned outside the cylinder 171 with respect to the opening 105 (the state shown in FIG. 15). That is, the second ink chamber 63 communicates with the first ink chamber 73 or the atmosphere through the opening 105.

  The frame 72 is provided with a hole 69 in the upper layer portion of the second ink chamber 63. A check valve 93 that opens and closes the hole 69 is disposed in the hole 69. The check valve 93 does not operate when the opening 105 is closed by the piston 181. That is, the check valve 93 operates in a state where the opening 105 is opened. The check valve 93 opens the hole 69 when the second ink chamber 63 has a positive pressure with respect to the cylinder 171. The check valve 93 closes the hole 89 when the second ink chamber 63 has a negative pressure in the cylinder 171.

  Since such check valves 95 and 93 are provided, the ink flows as follows. That is, as indicated by the arrow 24 in FIG. 4, the ink in the sub tank 21 (see FIG. 2) flows into the second ink chamber 63 through the ink tube 32. When this ink flows into the second ink chamber 63, the second ink chamber 63 becomes positive with respect to the first ink chamber 73, and the hole 89 is closed by the check valve 95. For this reason, the ink that has flowed from the sub tank 21 into the second ink chamber 63 is prevented from returning to the first ink chamber 73. Further, when air is supplied to the first ink chamber 73 by a pump 170 described later, the first ink chamber 73 becomes positive pressure with respect to the second ink chamber 63, and the hole 89 is opened by the check valve 95. . The ink stored in the first ink chamber 73 flows from the first ink chamber 73 to the second ink chamber 63 through the hole 89. Then, this ink is supplied to the sub tank 21 through the ink tube 32 provided with the ink extraction tube 149, as indicated by an arrow 23 in FIG.

  FIG. 4 shows a state where ink is injected into the first ink chamber 73 and the second ink chamber 63. In the first ink chamber 73, approximately 80% of the volume of the first ink chamber 73 is stored. That is, air is present together with ink in the first ink chamber 73. Thereby, an air layer 83 is formed in the upper layer portion of the first ink chamber 73 of the main tank 70. The first ink chamber 73 is sealed in a state where the piston 181 is located behind the opening 101 in the cylinder 171. Therefore, ink is stored in the first ink chamber 73 in a state where an airtight air layer 73 is formed. The ink cartridge 50 is provided with a pump 170 that sucks air from the air layer 83 and supplies the air to the air layer 83 to supply ink to the sub tank 21. The piston 181 is a part of the pump 170.

  As shown in FIG. 4, the pump 170 is roughly provided with a cylinder 171 and a plunger 172. The cylinder 171 and the plunger 172 are obtained by injection molding a synthetic resin.

  The cylinder 171 is configured by a case 72. The cylinder 171 is provided above the second ink chamber 63 so that one end portion in the longitudinal direction is accommodated in the first ink chamber 73 through the opening 77 as described above. The cylinder 171 is arranged so that its central axis is along the depth direction of the main tank 70 (X-axis direction in the drawing). With reference to the direction (insertion direction) in which the plunger 172 is inserted into the cylinder 171, the cylinder 171 has a wall 179 at the end on the far side in the insertion direction. A hole 173 is formed by the wall 179. Air in the cylinder 171 flows into and out of the first ink chamber 73 through the hole 173. An opening 174 is formed at the front end of the cylinder 171 with reference to the insertion direction. The opening 174 has the same size as the inner diameter of the cylinder 171. The plunger 172 is inserted into the cylinder 171 from the opening 174. The hole 173 and the opening 174 are coaxially disposed at both ends of the cylinder 171. Hereinafter, of the both ends of the cylinder 171, the end on the side where the hole 173 is provided is referred to as a front end 175, and the end on the side where the opening 174 is provided is referred to as a rear end 176.

  FIG. 5 is a plan view of the plunger 172.

  As shown in FIGS. 4 and 5, the plunger 172 includes a piston 181, a rod 182 (corresponding to a rod of the present invention), and a slide member 108 (an example of a movable member of the present invention).

  The piston 181 reciprocates in the cylinder 171. The piston 181 sucks air from the air layer 83 by moving the cylinder 171 from the front end 175 toward the rear end 176. The piston 181 supplies air to the air layer 83 by moving in the cylinder 171 from the rear end 176 toward the front end 175. Ink is supplied from the main tank 70 to the sub tank 21 by the reciprocating motion of the piston 181. The piston 181 is provided to be slidable with respect to the inner peripheral surface of the cylinder 171. On both sides of the piston 181 in the axial direction, closing members 166 and 167 (see FIG. 5) are provided. The closing members 166 and 167 are elastic members such as rubber whose outer diameter is slightly larger than the inner diameter of the cylinder 171. The piston 181 slides in the cylinder 171 in a state where the gap formed between the piston 181 and the inner peripheral surface of the cylinder 171 is sealed by providing the closing members 166 and 167.

  The rod 182 extends from the piston 181 to the outside (rear end 176 side) of the cylinder 171. In other words, the rod 182 is provided on the piston 181 so as to protrude to the outside of the ink cartridge 50 as shown in FIG. The rod 182 is set such that its axial length is longer than the axial length of the cylinder 171.

  A rack gear 185 is formed on the rod 182 as shown in FIGS. The rack gear 185 is formed on the upper side of the rod 182. The rack gear 185 meshes with a pinion gear 221 of a drive transmission mechanism 220 (see FIG. 7) described later. As a result, a driving force for sliding the piston 181 in the axial direction of the cylinder 171 (the left-right direction in FIG. 4) is transmitted to the piston 181 via the rod 182. That is, the piston 181 reciprocates in the cylinder 171 by the driving force applied to the rod 182. In response to the driving force, the piston 181 slides in the left direction in FIG. At that time, the air in the cylinder 171 is sent into the first ink chamber 73 through the hole 173. Further, upon receiving the driving force, the piston 181 slides in the right direction in FIG. At that time, the air in the first ink chamber 73 is drawn into the cylinder 171 through the hole 173. Thus, the piston 181 reciprocates in the cylinder 171 to supply air to the air layer 83 formed in the main tank 70 or to suck air from the air layer 83. Ink is supplied from the main tank 70 to the sub tank 21 by the reciprocating motion of the piston 181.

  The slide member 108 swings a sensor arm 150 (corresponding to the arm member of the present invention) described later. The slide member 108 is provided on the piston 181 so as to extend from the piston 181 into the first ink chamber 73. Therefore, in a state where the plunger 172 is inserted into the cylinder 171, the slide member 108 protrudes from the cylinder 171 through the hole 173 to the first ink chamber 73. Since the slide member 108 is provided on the piston 181, the slide member 108 reciprocates integrally with the piston 181 and the rod 182 by the driving force transmitted from the drive transmission mechanism 220 (see FIG. 7) to the rod 182. As described above, since the piston 181 is reciprocated with a simple configuration, the operation of the slide member 108 is easily performed.

  The slide member 108 is provided on the piston 181 so as to extend in the reciprocating direction of the piston 181. As shown in FIGS. 4 and 5, the slide member 108 is provided with an opening 109. The opening 109 is formed so as to penetrate vertically on the distal end side of the slide member 108. A sensor arm (light-shielding plate) 150 described later is swingably provided in the main tank 70 in a state where the first arm 155 is inserted through the opening 109. The sensor arm 150 swings in the same direction as the reciprocating direction of the plunger 172 (the left-right direction in FIG. 4). Therefore, the sensor arm 150 swings between a position where the first arm 155 contacts the opening end 126 of the opening 109 and a position where the first arm 155 contacts the opening end 127 of the opening 109. Since the slide member 108 reciprocates together with the piston 181, the positions of the open ends 126 and 127 of the slide member 108 change. Therefore, the range in which the sensor arm 150 can swing is changed depending on the position of the slide member 108.

  FIG. 6 is an enlarged perspective view of a VI portion in FIG.

  As shown in FIGS. 3, 4, and 6, the main tank 70 includes a detection unit 75. The detection unit 75 is for detecting the remaining amount of ink stored in the first ink chamber 73. As shown in FIGS. 3 and 4, the detection unit 75 protrudes outward from the upper surface of the main tank 70 in the Z-axis direction. For this reason, the detection part 75 protrudes outside from the upper surface 59 of the case 52 in the state in which the main tank 70 was accommodated in the case 52 (refer FIG. 6). The detection unit 75 is configured integrally with the frame 71. Therefore, the detection unit 75 is made of the same material as the frame 71, that is, a translucent synthetic resin. As will be described later, light is transmitted through the optical sensor 203 (see FIG. 10) in the detection unit 75. In the present embodiment, the detection unit 75 is made of a translucent material, but may be made of any material as long as it has optical transparency (transparency). Therefore, the detection unit 75 may be made completely transparent in order to improve the light transmittance.

  As shown in FIG. 6, the detection unit 75 has side walls 78 and 79 extending in the X-axis direction in FIG. The side walls 78 and 79 are opposed to each other with a predetermined interval in the width direction of the main tank 70 (Y-axis direction in FIG. 3). Thereby, the detection part 75 has the cavity part 76 (refer FIG. 4) between the side wall 78 and the side wall 79. FIG. The cavity 76 is continuous with the first ink chamber 73. A shielding portion 157 (see FIG. 4) of the sensor arm 150 (described later) enters or leaves the hollow portion 76. That is, the detection unit 75 has a space in which the shielding unit 157 (corresponding to the detector of the present invention) can move.

  As shown in FIG. 4, the main tank 70 has a support portion 97 at a substantially central position in the first ink chamber 73. The support part 97 supports the sensor arm 150 in a swingable manner. The support part 97 is provided integrally with the frame 71. The support portion 97 is pivotally supported so as to grip the connecting shaft 158 (see FIG. 4) of the sensor arm 150. Thereby, the sensor arm 150 is supported by the support portion 97 so as to be swingable. In the present embodiment, the specific gravity of the ink stored in the main tank 70 is heavier than the average specific gravity of the sensor arm 150. The sensor arm 150 receives buoyancy from the ink while being pivotally supported by the support portion 97. For this reason, the sensor arm 150 is swung by the buoyancy received from the ink.

  The sensor arm 150 is a member for detecting the remaining amount of ink stored in the first ink chamber 73. The sensor arm 150 is made of a synthetic resin and is obtained by injection molding. As shown in FIG. 4, the sensor arm 150 includes a connecting shaft 158, a first arm 155, a shielding part 157, a second arm 156, and a balance part 152. The connecting shaft 158 is pivotally supported by the support portion 97 so as to be rotatable. The first arm 155 and the second arm 156 are provided so as to extend in the radial direction from the rotation axis of the connecting shaft 158. The sensor arm 150 is provided with a shielding part 157. The shield 157 is provided at the tip of the first arm 155. As described above, the shielding portion 157 enters or leaves the cavity portion 76 when the sensor arm 150 is swung. The shielding portion 157 blocks the optical path of light passing through the side walls 78 and 79 at the cavity portion 76. The shielding part 157 is formed in a flat plate shape having a flat surface extending in the rotation direction of the sensor arm 150 (the direction indicated by the arrow 46 in FIG. 4). For this reason, the shielding portion 157 can reliably block the optical path when entering the predetermined position (the position shown in FIG. 4) of the cavity portion 76.

  The second arm 156 extends obliquely downward from the connecting shaft 158. A balance portion 152 is provided at the tip of the second arm 156. The balance portion 152 is shaped so that the average specific gravity is lighter than the specific gravity of the ink. Specifically, the balance part 152 is hollow inside. For this reason, the balance part 152 plays the role of a buoyancy body in the ink.

  As shown in FIG. 4, buoyancy is generated with respect to the balance portion 152 when the ink that allows the balance portion 152 to be completely immersed is stored in the first ink chamber 73. This buoyancy is greater than the gravity acting on the second arm 156 and the balance portion 152. Therefore, the sensor arm 150 rotates clockwise (the direction indicated by the arrow 48 in FIG. 13) about the connecting shaft 158. As described above, the sensor arm 150 swings due to the buoyancy generated with respect to the balance unit 152. In the state where the piston 181 is located on the back side of the cylinder 171 (the state shown in FIG. 4), the first arm 155 contacts the opening end 126 of the slide member 108. Thereby, the rotation of the sensor arm 150 is stopped, and the state where the shielding part 157 enters the detection part 75 is maintained. As shown in FIGS. 13 and 14, when the piston 181 moves toward the outside of the cylinder 171, the position of the opening end 126 moves toward the cylinder 171 in conjunction therewith. For this reason, the sensor arm 150 rotates in the direction of the arrow 48 (see FIG. 13), and the shielding portion 157 contacts the support wall 74. As a result, the rotation of the sensor arm 150 is restrained, and the state in which the shielding portion 157 has left the detection portion 75 is maintained.

  When the ink stored in the first ink chamber 73 decreases, as shown in FIG. 20, the balance part 152 is exposed from the ink surface, and the buoyancy with respect to the balance part 152 decreases. Thereby, the gravity which acts on the 2nd arm 156 and the balance part 152 becomes larger than the buoyancy which acts on these. For this reason, the sensor arm 150 is pulled in the direction of gravity of the balance unit 152. As a result, the sensor arm 150 rotates counterclockwise (the direction indicated by the arrow 47 in FIG. 20) about the connecting shaft 158. The shielding part 157 retreats from the cavity part 76 of the detection part 75 by this rotation. As shown in FIG. 20, when the shielding portion 157 comes into contact with the upper surface of the main tank 70, the rotation of the sensor arm 150 is stopped. At this time, the shielding unit 157 stops at a predetermined position where the shielding unit 157 has left the detection unit 75 (see FIG. 20).

  FIG. 7 is a perspective view showing an external configuration of the cartridge mounting unit 200, and shows a state where the ink cartridge 50 is removed from the cartridge mounting unit 200. FIG. FIG. 8 is a perspective view showing an external configuration of the cartridge mounting unit 200, and shows a state where the ink cartridge 50 is mounted on the cartridge mounting unit 200. FIG. 9 is a side view of the cartridge mounting portion 200 as viewed from the arrow IX of FIG. 7 to 9, the teeth formed on the pinion gear 221, the first transmission gear 225, and the second transmission gear 226 are omitted.

  The cartridge mounting unit 200 holds five ink cartridges 50 respectively corresponding to the five colors of ink. As described above, the five colors of ink are cyan (C), magenta (M), yellow (Y), photo black (PBk), and black (Bk). The cartridge mounting unit 200 is accommodated in the ink jet recording apparatus 10.

  The cartridge mounting part 200 includes a cartridge case 201 as shown in FIGS. An opening 202 is provided on the front surface of the cartridge case 201. The ink cartridge 50 is inserted from the opening 202. When the ink cartridge 50 inserted into the cartridge case 201 is pressed in the insertion direction (X-axis direction in the drawing), the ink extraction tube 149 (see FIG. 4) disposed at the back of the cartridge case 201 is inked. It is inserted into the supply valve 130 (see FIG. 4). Thereby, the mounting of the ink cartridge 50 to the cartridge case 201 is completed. The cartridge case 201 is configured such that the ink cartridge 50 can be inserted and removed.

  A drive transmission mechanism 220 is provided on the back side of the cartridge mounting unit 200. The drive transmission mechanism 220 includes five pinion gears 221, a shaft 222, a link rod 223, a shaft 224, a first transmission gear 225, and a second transmission gear 226.

  The pinion gear 221 is meshed with the rack gear 185 in a state where the ink cartridge 50 is mounted in the cartridge case 201. In the present embodiment, five pinion gears 221 are disposed corresponding to the five plungers 172 of the ink cartridge 50. As shown in FIGS. 7 to 9, the pinion gear 221 is formed in a substantially semicircular shape. Although not shown in the drawing, teeth that mesh with the rack gear 185 are formed on the arc portion 228 of the pinion gear 221.

  All of the five pinion gears 221 are fixed to the shaft 222. Therefore, when the shaft 222 rotates, all the pinion gears 221 rotate at the same rotational speed in the same direction as the rotation direction. A link rod 223 is connected to one end of the shaft 222. A predetermined driving force is transmitted to the shaft 222 by the link rod 223. The link rod 223 is also connected to the shaft 224. In short, one end of the link rod 223 is connected to the shaft 222 and the other end is connected to the shaft 224. A first transmission gear 225 is fixed to the shaft 224. The second transmission gear 226 is meshed with the first transmission gear 225.

  The second transmission gear 226 is connected to the LF motor 217 (see FIG. 11). The LF motor 217 is also coupled to a drive system such as a paper feed roller 12 (see FIG. 1) and a transport roller 13 (see FIG. 1) that constitute the inkjet recording apparatus 10. The LF motor 217 is controlled to perform a predetermined operation by a control unit 230 (see FIG. 11) that comprehensively controls the inkjet recording apparatus 10.

  When the driving force is transmitted from the LF motor 217 to the second transmission gear 226, the driving force is transmitted to the rack gear 185 via the first transmission gear 225, the shaft 224, the link rod 223, the shaft 222, and the pinion gear 221. As a result, the plunger 172 slides so as to reciprocate within the cylinder 171. In other words, the piston 181 and the rod 182 reciprocate in the cylinder 171 by the driving force transmitted from the LF motor 217. Since the slide member 108 is provided on the piston 181, it naturally reciprocates together with the piston 181 and the rod 182.

  FIG. 10 is a perspective view showing the light emitting element 205 and the light receiving element 207 of the optical sensor 203.

  As shown in FIGS. 7 to 10, an optical sensor 203 is provided on the upper surface 210 of the cartridge case 201. This optical sensor 203 detects the shielding part 157 of the detection part 75. In other words, the optical sensor 203 detects the shielding part 157 that has entered the cavity 76 of the detection part 75. The optical sensor 203 is a so-called transmissive optical sensor (Photointerrupter). As shown in FIGS. 9 and 10, the optical sensor 203 includes a light emitting element 205 and a light receiving element 207 arranged to face each other. The optical sensor 203 outputs a sensor signal (for example, an electrical signal corresponding to the luminance) based on the luminance of the light received by the light receiving element 207 from the light emitting element 205.

  The optical sensor 203 is provided corresponding to the ink cartridge 50. Therefore, in this embodiment, five optical sensors 203 are provided. A detection area 20 (see FIG. 10) is provided between the light emitting element 205 and the light receiving element 207. When the detection region 20 is open, the light from the light emitting element 205 is received by the light receiving element 207. When the light path from the light emitting element 205 to the light receiving element 207 is thus opened, a sensor signal corresponding to the intensity of the light received by the light receiving element 207 is output from the light receiving element 207. Conversely, when the detection region 20 is not open, the light from the light emitting element 205 is not received by the light receiving element 207. As described above, when the optical path of light from the light emitting element 205 to the light receiving element 207 is blocked, no current is output from the light receiving element 207.

  The optical sensor 203 is provided on the upper surface 210 of the cartridge case 201. Specifically, as shown in FIGS. 9 and 10, the optical sensor 203 is provided so that the light emitting element 205 and the light receiving element 207 protrude into the cartridge case 201 from the back side of the upper surface 210. The light emitting element 205 and the light receiving element 207 are arranged to face each other in a direction perpendicular to the paper surface of FIG. Therefore, when the ink cartridge 50 is mounted on the cartridge mounting unit 200, the detection unit 75 (see FIG. 3) enters the detection region 20 (see FIG. 10). As described above, the detection unit 75 is arranged in the detection region 20 of the optical sensor 203 when the ink cartridge 50 is mounted on the cartridge mounting unit 200 of the apparatus main body. Accordingly, the side walls 78 and 79 of the detection unit 75 are disposed between the light emitting element 205 and the light receiving element 207. Therefore, the optical sensor 203 can detect the shielding part 157 that has entered the detection part 75.

  In a state where the shielding portion 157 of the sensor arm 150 enters the detection portion 75 (the state shown in FIG. 4), the detection region 20 is shielded by the shielding portion 157. In other words, the light from the light emitting element 205 to the light receiving element 207 is blocked by the shielding portion 157. On the other hand, in a state where the shielding unit 157 has left the detection unit 75 (the state shown in FIGS. 13 and 20), the detection region 20 is not shielded. That is, light from the light emitting element 205 passes through the side walls 78 and 79 and is received by the light receiving element 207. For this reason, based on the sensor signal output from the sensor 203, it can be determined whether or not the shielding unit 157 has entered the detection unit 75.

  The shielding unit 157 leaves the detection unit 75 when the ink amount reaches a predetermined amount (see FIG. 20). Therefore, the optical sensor 203 detects whether or not the shielding unit 157 has entered the detection unit 75, and the control unit 230 determines whether or not the ink amount is a predetermined amount based on the detection result (see FIG. 11). Is determined.

  By the way, the sensor arm 150 is swingably provided in the main tank 70 with the first arm 155 inserted through the opening 109 of the slide member 108 (see FIG. 4). The shield 157 of the sensor arm 150 is detected by the sensor 203 when the first arm 155 is supported by the open end 126 (see FIG. 4) of the slide member 108 as described above. That is, when the slide member 108 moves from the state shown in FIG. 4, the shielding part 157 is not detected by the sensor 203 (see, for example, FIG. 13).

  The slide member 108 moves between the first position and the second position as the drive transmission mechanism 220 reciprocates the piston 181. Here, the first position is a position where the optical sensor 203 can detect the shielding part 157 in the detection part 75. In other words, the first position is a position where the slide member 108 supports the first arm 155 by the opening end 126 so that the shielding part 157 enters the detection region 20 of the detection part 75 (see FIG. 4). The second position is a position where the optical sensor 203 cannot detect the shielding unit 157 in the detection unit 75. In other words, the second position is a position where the slide member 108 has moved so that the shielding unit 157 moves out of the detection region 20 of the detection unit 75 (see, for example, FIG. 13). The second position is not limited to the position shown in FIG. In other words, other positions other than the position where the sensor arm 150 is supported by the slide member 108 so that the shielding portion 157 is positioned in the detection region 20 are included in the second position. However, this is not the case when the amount of ink is small. Therefore, the positions shown in FIGS. 13 to 18 are all included in the second position. 20 shows the first position instead of the second position because the slide member 108 is in the same position as that shown in FIG.

  FIG. 11 is a block diagram illustrating a configuration example of the control unit 230 of the inkjet recording apparatus 10.

  The control unit 230 controls the overall operation of the inkjet recording apparatus 10. As shown in FIG. 11, the control unit 230 mainly includes a CPU (Central Processing Unit) 231, a ROM (Read Only Memory) 232, a RAM (Random Access Memory) 233, and an EEPROM (Electrically Erasable and Programmable ROM) 234. It is configured as a microcomputer. The control unit 230 is connected to an ASIC (Application Specific Integrated Circuit) 189 via the bus 188.

  The ROM 232 stores a program for the CPU 231 to control various operations of the inkjet recording apparatus 10. The RAM 233 is used as a storage area or work area for temporarily recording various data used when the CPU 231 executes the program. The EEPROM 234 stores settings, flags, and the like that should be retained even after the power is turned off.

  A head control board 27 (see FIG. 1), a drive circuit 193, a drive circuit 194, an optical sensor 203 (see FIG. 8), an operation unit 212, and a display unit 213 are connected to the ASIC 189.

  The head control board 27 drives and controls the recording head 26 based on the image signal input from the ASIC 189. Thus, each color ink is selectively ejected from the nozzles 28 of the recording head 26 at a predetermined timing, and an image is recorded on the recording paper.

  The drive circuit 193 supplies a drive signal to the CR (carriage) motor 216 based on the phase excitation signal or the like input from the ASIC 189. When the CR motor 216 receives the drive signal, the reciprocation of the carriage 30 (see FIG. 1) is controlled.

  The drive circuit 194 drives the LF motor 217. A paper feed roller 12 (see FIG. 1), a transport roller 13 (see FIG. 1), and a plunger 172 (see FIG. 8) are connected to the LF motor 217. The drive circuit 194 receives the output signal from the ASIC 189 and drives the LF motor 217. The driving force of the LF motor 217 is selectively transmitted to the paper feed roller 12, the transport rollers 13A and 13B, and the plunger 172.

  When an image is recorded by the recording head 26, the driving force of the LF motor 217 is transmitted to the paper feed roller 12 and the transport rollers 13A and 13B. As a result, the recording paper is conveyed from the paper feed tray 16 to the paper discharge tray 17 along the conveyance path 18. The drive circuit 194 switches the drive of the LF motor 217 so that the driving force of the LF motor 217 is transmitted to the drive transmission mechanism 220 instead of the paper feed roller 12 and the transport rollers 13A and 13B. The plunger 172 is connected to the LF motor 217 when the rack gear 185 and the pinion gear 221 are engaged with each other. That is, the plunger 172 is connected to the LF motor 217 in a state where the ink cartridge 50 is mounted on the cartridge mounting unit 200. When the ink supply operation from the main tank 70 to the sub tank 21 is performed when the ink cartridge 50 is mounted, the driving force of the LF motor 217 is transmitted to the plunger 172. The plunger 172 receives the driving force in a state where the rack gear 185 (see FIG. 8) is engaged with the pinion gear 221 (see FIG. 8).

  The optical sensor 203 (see FIG. 10) outputs a sensor signal. In the present embodiment, this sensor signal is an analog electrical signal corresponding to the luminance of the light received by the light receiving element 207 from the light emitting element 205. For this reason, the optical sensor 203 outputs different sensor signals depending on whether or not the shielding portion 157 has entered the detection region 20 (see FIG. 10). Specifically, the sensor signal in a state where the detection region 20 (see FIG. 10) is opened (see, for example, FIG. 13) is more than the sensor signal in the state where the detection region 20 is shielded by the shielding unit 157 (see FIG. 4). Is also a high value. The control unit 230 determines that the sensor 203 is in an ON state on condition that the sensor signal output from the sensor 203 is less than a predetermined threshold value. That is, the control unit 230 determines that the shielding unit 157 has entered the detection area 20. The control unit 230 determines that the sensor 203 is in an OFF state on condition that the sensor signal output from the sensor 203 is equal to or greater than a predetermined threshold value. That is, the control unit 230 determines that the shielding unit 157 has left the detection region 20 and the detection region 20 is open. As described above, the control unit 230 determines the state of the ink cartridge 50 based on the detection result of the sensor 203. Specifically, the control unit 230 determines whether or not the ink amount is a predetermined amount, determines the operating state of the slide member 108, and determines the mounting state of the ink cartridge 50. Note that these determination processes will be described in detail later.

  The operation unit 212 includes input keys and the like for a user to input information. Various operation inputs by the user are received by the operation unit 212. The display unit 213 displays various setting information, the operation state of the inkjet recording apparatus 10, and the like, and includes, for example, a liquid crystal display (Liquid Crystal Display). Notification to the user is performed from the display unit 213.

  FIG. 12 is a flowchart illustrating an example of a processing operation performed in the ink jet recording apparatus 10 when the ink cartridge 50 is mounted. FIG. 13 is a cross-sectional view showing the internal structure of the ink cartridge 50, and shows how the plunger 172 moves toward the outside of the cylinder 171.

  Hereinafter, a processing operation performed in the inkjet recording apparatus 10 when the ink cartridge 50 is mounted in the cartridge mounting unit 200 will be described with reference to FIGS. 12 and 13. The processing operation shown in the flowchart of FIG. 12 is performed when the ink cartridge 50 is mounted. When the ink cartridge 50 is mounted, a door (cover) that exposes the cartridge mounting unit 200 to the outside of the inkjet recording apparatus 10 is opened and closed. Therefore, the processing operation is performed when, for example, a sensor provided separately from the optical sensor 203 detects that the door is changed from the opened state to the closed state. The main tank 70 stores ink in a state where an airtight air layer 83 is formed. When the pinion gear 221 is not engaged with the rack gear 185, the pressure of the air layer 83 is set so that the slide member 108 is in the first position (see FIG. 4). Therefore, when the ink cartridge 50 is mounted by a correct operation, the shielding portion 157 of the sensor arm 150 enters the detection portion 75 and is detected by the sensor 203.

  First, the control unit 230 determines whether the sensor 203 is in an ON state or an OFF state based on a sensor signal output from the sensor 203 (S1). When it is determined that the sensor 203 is in the OFF state (S1: OFF), the control unit 230 determines that the shielding unit 157 has not entered the detection unit 75 and notifies a mounting error (S2). That is, the control unit 230 determines that the ink cartridge 50 is not correctly mounted on the cartridge mounting unit 200 and notifies a mounting error. Specifically, the control unit 230 causes the display unit 213 to display a message such as “Please reset the ink cartridge”. The notification of the mounting error is not limited to the message display, but may be a voice message output, a message display and a voice output together. When the processing operation in step S2 is performed, the process returns to step S1.

  When the control unit 230 determines that the sensor 203 is in the ON state (S1: ON), the control unit 230 determines that the shielding unit 157 has entered the detection unit 75, and LF motor 217 to suck air from the air layer 83. Is driven (S3). And the control part 230 judges whether the sensor 203 is an ON state or an OFF state based on the sensor signal output from the sensor 203 (S4).

  When the driving force of the LF motor 217 is normally transmitted to the rack gear 185 (see FIG. 8) by the processing operation in step S3, as shown in FIG. 13, the plunger 172 moves outside the cylinder 171 (rightward in FIG. 13). ). Thereby, as apparent from FIGS. 4 and 13, the position of the opening end 126 is moved to the cylinder 171 side. Thereby, the slide member 108 moves from the first position to the second position. Therefore, the sensor arm 150 rotates in the direction of the arrow 81 in FIG. 13 by the buoyancy acting on the balance unit 152. For this reason, the shielding part 157 leaves the detection area 20, and the sensor 203 is turned off. Conversely, when the driving force of the LF motor 217 is not normally transmitted to the rack gear 185, that is, when the rack gear 185 and the pinion gear 221 are not meshed so as to be able to transmit the driving force, the plunger 172 moves even if the LF motor 217 is driven. Not. For this reason, the state (state shown in FIG. 4) where the shielding part 157 is located in the detection region 20 is maintained, and the sensor 203 remains in the ON state. That is, the state where the slide member 108 is in the first position is maintained.

  When it is determined that the sensor 203 remains in the ON state (S4: ON), the control unit 230 notifies a drive transmission error (S5). Specifically, the control unit 230 displays a message such as “the piston is not operating normally” on the display unit 213. The notification of the drive transmission error is not limited to the message display, but may be a voice message output or a message display and voice output together.

  When it is determined that the sensor 203 has changed from the ON state to the OFF state (S4: OFF), the control unit 230 drives the LF motor 217 to supply air to the air layer 83 (S6). And the control part 230 judges whether the sensor 203 is an ON state or an OFF state based on the sensor signal output from the sensor 203 (S7).

  By the processing operation in step S6, the driving force of the LF motor 217 is transmitted to the rack gear 185 (see FIG. 8), and the plunger 172 is pushed toward the back side of the cylinder 171 (the left direction in FIG. 18). In addition, since it is confirmed that the drive transmission is normally performed in step S4, the driving force of the LF motor 217 is correctly transmitted to the plunger 172. As a result, as shown in FIGS. 16 to 18, the position of the opening end 126 is moved away from the cylinder 171. Accordingly, the sensor arm 150 rotates in the direction of the arrow 85 in FIG. 18 when the first arm 155 is pressed against the opening end 126. For this reason, as shown in FIG. 4, the shielding portion 157 enters the detection region 20, and the sensor 203 changes from the OFF state to the ON state. That is, the slide member 108 moves from the second position to the first position.

  When it is determined that the sensor 203 remains in the OFF state (S7: OFF), the control unit 230 continues the processing operation in step S6. When it is determined that the sensor 203 has changed from the OFF state to the ON state (S7: ON), the control unit 230 determines that the slide member 108 has been returned to the first position. In other words, the control unit 230 is also referred to as a position where the first arm 155 is supported by the opening end 126 (hereinafter referred to as “reference position”) so that the state where the shielding unit 157 enters the detection unit 75 is maintained. It is determined that the slide member 108 has been moved until. Thus, when the control unit 230 determines “ON” in step S7, the processing operation is completed.

  As described above, the detection unit 75 is not disposed in the detection region 20 of the optical sensor 203 (see FIG. 10) before the ink cartridge 50 is mounted in the cartridge mounting unit 200. For this reason, even if the shielding unit 157 enters the detection unit 75, the shielding unit 157 is not detected by the optical sensor 203. When the ink cartridge 50 is mounted on the cartridge mounting unit 200, the detection unit 75 is disposed in the detection region 20. For this reason, the shielding part 157 located in the detection part 75 is detected by the optical sensor 203. That is, the mounting state of the ink cartridge 50 is determined by performing the processing operation of step S1 based on the detection result of the optical sensor 203. That is, it is possible to determine whether or not the ink cartridge 50 has been normally mounted by using the optical sensor 203 that is used to determine whether or not the ink amount is a predetermined amount.

  Further, the slide member 108 moves between a first position (see FIG. 4) and a second position (for example, see FIG. 13). In a state where the slide member 108 is in the first position, the shielding portion 157 is moved to the detection portion 75, and thus the shielding portion 157 is detected by the optical sensor 203. In the state where the slide member 108 is in the second position, the shielding part 157 is retracted from the detection part 75, so that the shielding part 157 is not detected by the optical sensor 203. For this reason, based on the detection result of the optical sensor 203 when the processing operation in step S3 is performed, the operation state of the slide member 108 is determined as in step S4. That is, the operation state of the slide member 108 can be determined using the optical sensor 203 used for determining whether or not the ink amount is a predetermined amount. In other words, it is determined whether or not the driving force of the LF motor 217 is correctly transmitted to the plunger 172.

  Next, the ink supply operation from the main tank 70 to the sub tank 21 will be described with reference to FIGS.

  FIG. 14 is a cross-sectional view showing the internal structure of the ink cartridge 50 and shows a state in which the shielding portion 157 is in contact with the support wall 74. FIG. 15 is a cross-sectional view showing the internal structure of the ink cartridge 50, and shows a state where the first ink chamber 73 and the second ink chamber 63 are communicated. FIG. 16 is a cross-sectional view showing the internal structure of the ink cartridge 50, and shows a state in which the first ink chamber 73 and the second ink chamber 63 are opened to the atmosphere. FIG. 17 is a cross-sectional view showing the internal structure of the ink cartridge 50, and shows how ink is supplied from the main tank 70 to the recording head 26. FIG. 18 is a cross-sectional view showing the internal structure of the ink cartridge 50, and shows how the sensor arm 150 is swung by the slide member 108.

  When supplying ink from the main tank 70 to the sub tank 21, the control unit 230 drives the LF motor 217 to suck air from the air layer 83. As a result, the driving force of the LF motor 217 is transmitted to the rack gear 185 (see FIG. 8), and as shown in FIGS. 4, 13, and 14, the plunger 172 is outside the cylinder 171 (rightward in each figure). It is pulled out toward. Thereby, the pressure of the air layer 83 is gradually reduced as the plunger 172 moves. At this time, since the first ink chamber 73 has a negative pressure relative to the second ink chamber 63, the hole 89 is closed by the check valve 95. In the state shown in FIG. 14, since the opening 105 is closed by the piston 181, the check valve 93 does not operate.

  As shown in FIG. 15, when the plunger 172 is further pulled out of the cylinder 171 from the state shown in FIG. 14, the opening 105 is opened. Thereby, the first ink chamber 73 and the second ink chamber 63 are communicated with each other. Since the pressure of the air layer 83 is reduced, the hole 69 is opened by the check valve 93 and the air in the second ink chamber 63 is sucked into the cylinder 171. The second ink chamber 63 is connected to the sub tank 21 (see FIG. 1) via the ink tube 32 by the ink supply valve 130. The sub tank 21 has an opening 42 as shown in FIG. For this reason, when the air in the second ink chamber 63 is sucked into the cylinder 171, the ink in the sub tank 21 and the ink tube 32 is transferred to the second ink chamber 63 as indicated by the broken line arrow 25 in FIG. 15. Flow into. At this time, the bubbles 36 (see FIG. 15) that have flowed into the second ink chamber 63 are separated from the ink in the second ink chamber 63. For this reason, the bubble 36 is prevented from entering the first ink chamber 73.

  As shown in FIG. 16, when the plunger 172 is further pulled out of the cylinder 171 from the state shown in FIG. 15, the opening 101 is opened. As a result, the first ink chamber 73 and the second ink chamber 63 are opened to the atmosphere through the opening 101. Since the first ink chamber 73 and the second ink chamber 63 are depressurized by the movement of the piston 181, air flows into the cylinder 171 from the opening 101. Therefore, the air pressure in the first ink chamber 73 and the second ink chamber 63 is returned to the atmospheric pressure side.

  Subsequently, the control unit 230 drives the LF motor 217 to supply air to the air layer 83. As a result, the driving force of the LF motor 217 is transmitted to the rack gear 185 (see FIG. 8), and the plunger 172 is pushed into the back side of the cylinder 171 (to the left in each figure) as shown in FIGS. . As shown in FIG. 17, when the piston 181 moves until the closing member 166 (see FIG. 5) is located behind the opening 101 in the cylinder 171 (left side in FIG. 17), the opening 101 is closed by the piston 181. The Thereby, the air layer 83 in an airtight state is formed again in the first ink chamber 73 and the cylinder 171.

  As shown in FIG. 18, when the plunger 172 is further pushed into the inner side of the cylinder 171 from the state shown in FIG. 17, the air in the cylinder 171 is further supplied to the air layer 83. As a result, the pressure of the air layer 83 gradually increases, so that the first ink chamber 73 becomes a positive pressure with respect to the second ink chamber 63. Therefore, the hole 89 is opened by the check valve 95 and the ink in the first ink chamber 73 flows into the second ink chamber 63. This ink is sent out from the second ink chamber 63 to the sub tank 21 (see FIG. 1) via the ink extraction tube 149, as indicated by an arrow 23 (see FIG. 18).

  In this way, air is sucked from the air layer 83 formed in the main tank 70, and then the plunger 172 is reciprocated so as to supply air to the air layer 83, whereby the main tank 70 moves to the sub tank 21. Ink is supplied.

  Next, processing operations performed in the inkjet recording apparatus 10 when ink is supplied from the main tank 70 to the sub tank 21 as described above will be described with reference to FIGS. 19 and 20. The slide member 108 is located at the reference position (see FIG. 4). That is, the first arm 155 is in contact with the opening end 126 so that the state where the shielding unit 157 enters the detection unit 75 is maintained.

  FIG. 19 is a flowchart illustrating an example of a processing operation performed in the inkjet recording apparatus 10 when it is determined that it is necessary to supply ink. FIG. 20 is a cross-sectional view showing the internal structure of the ink cartridge 50 and shows how the sensor arm 150 is swung as the ink amount in the main tank 70 decreases.

  The controller 230 determines whether or not it is necessary to supply ink from the main tank 70 to the sub tank 21 (S11). This determination is made, for example, by counting the amount of ink ejected from the nozzles 28 of the recording head 26 with a dot counter (not shown) and detecting the remaining amount of ink in the sub tank 21. When it is determined that the ink needs to be supplied to the sub tank 21 (S11: YES), the controller 230 drives the LF motor 217 to suck air from the air layer 83 (S12). As a result, as shown in FIGS. 4 and 13 to 16, the plunger 172 is moved toward the outside of the cylinder 171 (the right side of each figure). In addition, since the movement of the plunger 172 at that time has already been described, a detailed description thereof is omitted here.

  Following the processing operation of step S12, the controller 230 determines whether the sensor 203 is in an ON state or an OFF state based on a sensor signal output from the sensor 203 (S13).

  When the driving force of the LF motor 217 is normally transmitted to the rack gear 185 (see FIG. 8) by the processing operation of step S12, the plunger 172 is pulled out toward the outside of the cylinder 171 (see FIGS. 13 to 16). The position of the opening end 126 moves toward the cylinder 171 by the movement of the plunger 172 (see FIGS. 4 and 13 to 16). Thereby, the sensor arm 150 is rotated in the direction of the arrow 81 (see FIG. 13) by the buoyancy acting on the balance unit 152. For this reason, as shown in FIGS. 13 to 16, the shielding portion 157 is withdrawn from the detection region 20, and the sensor 203 is changed from the ON state to the OFF state. As a result, the slide member 108 moves from the first position (see FIG. 4) to the second position (see FIGS. 13 to 16). As shown in FIGS. 14 to 16, the sensor arm 150 is restrained in a state where the shielding portion 157 is in contact with the support wall 74. Conversely, when the driving force of the LF motor 217 is not normally transmitted to the rack gear 185, the plunger 172 is not moved as described above. For this reason, the state in which the shielding part 157 is located in the detection region 20 is maintained, and the sensor 203 remains in the ON state. That is, the state where the slide member 108 is in the first position is maintained.

  When it is determined that the sensor 203 remains in the ON state (S13: ON), the control unit 230 notifies a drive transmission error (S14). The processing operation in step S14 is performed in the same manner as the processing operation in step S5.

  When it is determined that the sensor 203 has been turned off (S13: OFF), the control unit 230 drives the LF motor 217 to supply air to the air layer 83 (S15). The processing operation in step S15 is performed in the same manner as the processing operation in step S6. And the control part 230 judges whether the sensor 203 is an ON state or an OFF state based on the sensor signal output from the sensor 203 (S16).

  When the LF motor 217 is driven by the process of step S15, the plunger 172 moves toward the back side of the cylinder 171 as described above (see FIGS. 16 to 18). As a result, the first arm 155 is pressed by the opening end 126 of the slide member 108, and the shielding portion 157 enters the detection portion 75. For this reason, the sensor 203 changes from the OFF state to the ON state.

  By the way, ink is supplied from the main tank 70 to the sub tank 21 by performing the processing operations of step S12 and step S15. For this reason, the amount of ink stored in the main tank 70 decreases every time the ink supply operation is performed. As shown in FIG. 20, when the ink amount in the first ink chamber 73 decreases and the balance unit 152 is exposed from the ink surface, the gravity acting on the balance unit 152 and the second arm 156 is reduced. It becomes larger than the buoyancy acting on 152. Therefore, as shown in FIG. 20, the sensor arm 150 rotates in the direction indicated by the arrow 47. Accordingly, the shielding unit 157 leaves the detection unit 75. For this reason, when the ink is reduced to a predetermined amount, even if the slide member 108 is returned to the first position (see FIG. 20) by the processing operation in step S15, the sensor 203 does not change from the OFF state to the ON state.

  When it is determined that the sensor 203 remains in the OFF state (S16: NO), the control unit 230 notifies ink empty (S17). Specifically, the control unit 230 displays a message notifying that the remaining amount of ink is low, such as “Replace the ink cartridge” on the display unit 213. The notification of ink empty is not limited to the message display, and may be an output of a voice message or the like. When determining that the sensor 203 has changed from the OFF state to the ON state (S16: ON), the control unit 230 determines that the ink amount in the main tank 70 has not decreased to a predetermined amount and completes the processing operation. . That is, it is determined that there is no need to replace the ink cartridge 50, and the processing operation is completed.

  As described above, in the inkjet recording apparatus 10 according to the present embodiment, three determination processes are performed based on the detection result of the optical sensor 203. The three determination processes are determination of whether the ink amount is a predetermined amount, determination of the operating state of the slide member 108, and determination of the mounting state of the ink cartridge 50. Accordingly, the above three determination processes can be performed by one optical sensor 203, and the detection apparatus of the present invention (in the present embodiment, the ink jet recording apparatus 10) can be configured at low cost.

  Incidentally, in the process in which the ink stored in the sub tank 21 is consumed, bubbles are generated because the recording head 26 reciprocates. In the inkjet recording apparatus 10 according to the present embodiment, the bubbles 36 (see FIG. 15) are separated from the ink in the second ink chamber 63. Therefore, the bubbles 36 are effectively suppressed from adhering to the sensor arm 150. However, depending on the configuration of the main tank 70, air bubbles contained in the ink returned from the sub tank 21 may adhere to the sensor arm 150. In particular, since the sensor arm 150 is swung by buoyancy with respect to the balance portion 152, buoyancy independent of the ink amount acts on the sensor arm 150. For this reason, when air bubbles adhere to the sensor arm 150, normal swinging of the sensor arm 150 is hindered.

  The sensor arm 150 is swingably provided in a state where the first arm 155 is inserted through the opening 109 of the slide member 108. For this reason, when the slide member 108 reciprocates together with the piston 181, the sensor arm 150 is swung by the slide member 108 in the directions indicated by the arrows 81 and 85. Bubbles attached to the sensor arm 150 are shaken off from the sensor arm 150, and buoyancy due to the bubbles is removed from the sensor arm 150. As a result, the sensor arm 150 is normally swung, and the ink amount is accurately determined. As described above, the slide member 108 is reciprocated when the operation state of the slide member 108 is determined and when ink is supplied from the main tank 70 to the sub tank 21. Accordingly, it is possible to remove bubbles from the sensor arm 150 in accordance with the determination of the operation state of the slide member 108 and the ink supply operation.

  Although the case where the movable member of the present invention is the slide member 108 has been described in the present embodiment, the movable member is not limited to the slide member 108. For example, the movable member may reciprocate between a position where the sensor arm 150 comes into contact with the sensor arm 150 and the position where the movable member moves away from the sensor arm 150. Further, the movable member may swing the sensor arm 150 by rotating, for example.

FIG. 1 is a schematic cross-sectional view showing an internal mechanism of the ink jet recording apparatus 10. FIG. 2 is an enlarged view of a main part showing the recording unit 14 in FIG. 1 in detail. FIG. 2A shows a state where the opening 42 of the valve 37 is closed, and FIG. 2B shows the state where the opening 42 of the valve 37 is opened. Indicates the state. FIG. 3 is a perspective view showing an external configuration of the ink cartridge 50. FIG. 4 is a longitudinal sectional view showing the internal structure of the ink cartridge 50. FIG. 5 is a plan view of the plunger 172. FIG. 6 is an enlarged perspective view of a VI portion in FIG. FIG. 7 is a perspective view showing an external configuration of the cartridge mounting unit 200, and shows a state where the ink cartridge 50 is removed from the cartridge mounting unit 200. FIG. FIG. 8 is a perspective view showing an external configuration of the cartridge mounting unit 200, and shows a state where the ink cartridge 50 is mounted on the cartridge mounting unit 200. FIG. 9 is a side view of the cartridge mounting portion 200 as viewed from the arrow IX of FIG. FIG. 10 is a perspective view showing the light emitting element 205 and the light receiving element 207 of the optical sensor 203. FIG. 11 is a block diagram illustrating a configuration example of the control unit 230 of the inkjet recording apparatus 10. FIG. 12 is a flowchart illustrating an example of a processing operation performed in the ink jet recording apparatus 10 when the ink cartridge 50 is mounted. FIG. 13 is a cross-sectional view showing the internal structure of the ink cartridge 50, and shows how the plunger 172 moves toward the outside of the cylinder 171. FIG. 14 is a cross-sectional view showing the internal structure of the ink cartridge 50 and shows a state in which the shielding portion 157 is in contact with the support wall 74. FIG. 15 is a cross-sectional view showing the internal structure of the ink cartridge 50, and shows a state where the first ink chamber 73 and the second ink chamber 63 are communicated. FIG. 16 is a cross-sectional view showing the internal structure of the ink cartridge 50, and shows a state in which the first ink chamber 73 and the second ink chamber 63 are opened to the atmosphere. FIG. 17 is a cross-sectional view showing the internal structure of the ink cartridge 50, and shows how ink is supplied from the main tank 70 to the recording head 26. FIG. 18 is a cross-sectional view showing the internal structure of the ink cartridge 50, and shows how the sensor arm 150 is swung by the slide member 108. FIG. 19 is a flowchart illustrating an example of a processing operation performed in the inkjet recording apparatus 10 when it is determined that it is necessary to supply ink. FIG. 20 is a cross-sectional view showing the internal structure of the ink cartridge 50 and shows how the sensor arm 150 is swung as the ink amount in the main tank 70 decreases.

10. Inkjet recording apparatus (application example of the detection apparatus of the present invention)
50: Ink cartridge 70: Main tank (corresponding to the ink tank of the present invention)
75... Detection unit 83... Air layer 108... Slide member (an example of the movable member of the present invention)
150... Sensor arm (an example of the arm member of the present invention)
157 ... Shielding part (an example of the detector of the present invention)
171 ... Cylinder (corresponding to the cylinder of the present invention)
181 ... Piston (corresponding to the piston of the present invention)
182 ... Rod (corresponding to the rod of the present invention)
203... Optical sensor (an example of the sensor of the present invention)
230... Control unit (corresponding to the determination unit of the present invention)

Claims (5)

An ink cartridge having an ink tank for storing ink;
An arm member swingably provided on the ink tank;
A detector provided on the arm member;
A sensor for detecting the detector;
A determination unit that determines an ink amount based on a detection result of the sensor;
A movable member that swings the arm member ,
The movable member moves between a first position where the detector can be detected and a second position where the detector cannot be detected.
The said determination part is a detection apparatus which determines the operation state of the said movable member based on the detection result of the said sensor .   The detection device according to claim 1, wherein a specific gravity of the ink stored in the ink tank is heavier than an average specific gravity of the arm member. The ink cartridge includes a piston that reciprocates in a cylinder to supply air to an air layer formed in the ink tank or to suck air from the air layer,
The detection device according to claim 1, wherein the movable member is a slide member provided on the piston. The piston is provided with a rod extending to the outside of the cylinder,
The detection device according to claim 3, wherein the piston is reciprocated by a driving force applied to the rod. A detection unit disposed in a detection region of the sensor by mounting the ink cartridge in the apparatus main body;
The detection device according to claim 1 , wherein the determination unit determines a mounting state of the ink cartridge based on a detection result of the sensor.

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